ipaacalib/java/src/ipaaca/AbstractIU.java

@@ -32,6 +32,7 @@
 
 package ipaaca;
 
+import ipaaca.protobuf.Ipaaca.IU;
 import ipaaca.protobuf.Ipaaca.PayloadItem;
 
 import java.util.ArrayList;
@@ -59,9 +60,11 @@ public abstract class AbstractIU
     protected boolean committed = false;
     protected boolean retracted = false;
     private String uid;
-    protected int revision;
+    protected long revision;
     private boolean readOnly = false;
 
+    public abstract IU.AccessMode getAccessMode();
+    
     protected SetMultimap<String, String> links = HashMultimap.create();
     private final SetMultimap<String, String> EMPTYLINKS = HashMultimap.create();
 
@@ -147,7 +150,7 @@ public abstract class AbstractIU
         this.readOnly = readOnly;
     }
 
-    public void setRevision(int revision)
+    public void setRevision(long revision)
     {
         this.revision = revision;
     }
@@ -187,7 +190,7 @@ public abstract class AbstractIU
         return buffer;
     }
 
-    public int getRevision()
+    public long getRevision()
     {
         return revision;
     }

ipaacalib/java/src/ipaaca/IUConverter.java

@@ -88,12 +88,8 @@ public class IUConverter implements Converter<ByteBuffer>
             links.add(LinkSet.newBuilder().setType(entry.getKey()).addAllTargets(entry.getValue()).build());
         }
 
-        IU.AccessMode accessMode = IU.AccessMode.PUSH;
-        if(iua instanceof RemoteMessageIU || iua instanceof LocalMessageIU)
-        {
-            accessMode = IU.AccessMode.MESSAGE;
-        }
-        IU iu = IU.newBuilder().setUid(iua.getUid()).setRevision(iua.getRevision()).setCategory(iua.getCategory())
+        IU.AccessMode accessMode = iua.getAccessMode();
+        IU iu = IU.newBuilder().setUid(iua.getUid()).setRevision((int) iua.getRevision()).setCategory(iua.getCategory())
                 .setOwnerName(iua.getOwnerName()).setCommitted(iua.isCommitted()).setAccessMode(accessMode)
                 .setReadOnly(iua.isReadOnly()).setPayloadType("STR").addAllPayload(payloadItems).addAllLinks(links).build();
         String wireFormat = (accessMode == IU.AccessMode.MESSAGE) ? "ipaaca-messageiu" : "ipaaca-iu";

ipaacalib/java/src/ipaaca/InputBuffer.java

@@ -483,10 +483,10 @@ public class InputBuffer extends Buffer
             rServer = getRemoteServer(writerName);
         if ((rServer != null)&&(uid != null)) {
             IUResendRequest iurr = IUResendRequest.newBuilder().setUid(uid).setHiddenScopeName(hiddenScopeName).build();
-            int rRevision = 0;
+            long rRevision = 0;
             try
                 {
-                    rRevision = (Integer) rServer.call("resendRequest", iurr);
+                    rRevision = (Long) rServer.call("resendRequest", iurr);
                 }
                 catch (RSBException e)
                 {
@@ -500,6 +500,10 @@ public class InputBuffer extends Buffer
                 {
                     throw new RuntimeException(e);
                 }
+                catch (InterruptedException e)
+                {
+                    throw new RuntimeException(e);
+                }
             if (rRevision == 0)
             {
                 //throw new IUResendFailedException(aiu); // TODO

ipaacalib/java/src/ipaaca/LocalIU.java

@@ -32,6 +32,7 @@
 
 package ipaaca;
 
+import ipaaca.protobuf.Ipaaca.IU;
 import ipaaca.protobuf.Ipaaca.IULinkUpdate;
 import ipaaca.protobuf.Ipaaca.IUPayloadUpdate;
 import ipaaca.protobuf.Ipaaca.IUPayloadUpdate.Builder;
@@ -50,6 +51,11 @@ import com.google.common.collect.SetMultimap;
 
 public class LocalIU extends AbstractIU
 {
+    
+    public IU.AccessMode getAccessMode()
+    {
+        return IU.AccessMode.PUSH;
+    }
 
     private OutputBuffer outputBuffer;
 
@@ -205,7 +211,7 @@ public class LocalIU extends AbstractIU
                     removeSet.add(LinkSet.newBuilder().setType(entry.getKey()).addAllTargets(entry.getValue()).build());
                 }
                 outputBuffer.sendIULinkUpdate(this,
-                        IULinkUpdate.newBuilder().setUid(getUid()).setRevision(getRevision()).setWriterName(wName).setIsDelta(isDelta)
+                        IULinkUpdate.newBuilder().setUid(getUid()).setRevision((int) getRevision()).setWriterName(wName).setIsDelta(isDelta)
                                 .addAllNewLinks(addSet).addAllLinksToRemove(removeSet).build());
             }
         }
@@ -260,7 +266,7 @@ public class LocalIU extends AbstractIU
                 // send update to remote holders
                 PayloadItem newItem = PayloadItem.newBuilder().setKey(key).setValue(value).setType("STR")
                         .build();
-                IUPayloadUpdate update = IUPayloadUpdate.newBuilder().setUid(getUid()).setRevision(getRevision()).setIsDelta(true)
+                IUPayloadUpdate update = IUPayloadUpdate.newBuilder().setUid(getUid()).setRevision((int) getRevision()).setIsDelta(true)
                         .setWriterName(writer == null ? getOwnerName() : writer).addNewItems(newItem).build();
                 getOutputBuffer().sendIUPayloadUpdate(this, update);
             }
@@ -284,7 +290,7 @@ public class LocalIU extends AbstractIU
             increaseRevisionNumber();
             if (isPublished())
             {
-            	Builder builder = IUPayloadUpdate.newBuilder().setUid(getUid()).setRevision(getRevision()).setIsDelta(true)
+            	Builder builder = IUPayloadUpdate.newBuilder().setUid(getUid()).setRevision((int) getRevision()).setIsDelta(true)
                         .setWriterName(writer == null ? getOwnerName() : writer);
             	for (Map.Entry<? extends String, ? extends String> item : newItems.entrySet())
             	{
@@ -342,7 +348,7 @@ public class LocalIU extends AbstractIU
             if (isPublished())
             {
                 // send update to remote holders
-                IUPayloadUpdate update = IUPayloadUpdate.newBuilder().setUid(getUid()).setRevision(getRevision()).setIsDelta(true)
+                IUPayloadUpdate update = IUPayloadUpdate.newBuilder().setUid(getUid()).setRevision((int) getRevision()).setIsDelta(true)
                         .setWriterName(writer == null ? getOwnerName() : writer).addKeysToRemove((String) key).build();
                 getOutputBuffer().sendIUPayloadUpdate(this, update);
             }
@@ -355,7 +361,7 @@ public class LocalIU extends AbstractIU
     {
         if (isPublished())
         {
-            IUPayloadUpdate update = IUPayloadUpdate.newBuilder().setUid(getUid()).setRevision(getRevision()).setIsDelta(false)
+            IUPayloadUpdate update = IUPayloadUpdate.newBuilder().setUid(getUid()).setRevision((int) getRevision()).setIsDelta(false)
                     .setWriterName(writerName == null ? getOwnerName() : writerName).addAllNewItems(newPayload).build();
             getOutputBuffer().sendIUPayloadUpdate(this, update);
         }

ipaacalib/java/src/ipaaca/LocalMessageIU.java

@@ -32,6 +32,7 @@
 
 package ipaaca;
 
+import ipaaca.protobuf.Ipaaca.IU;
 
 /**
  * Local IU of Message sub-type. Can be handled like a normal IU, but on the remote side it is only existent during the handler calls.
@@ -50,4 +51,9 @@ public class LocalMessageIU extends LocalIU
         super(category);
     }
 
+    public IU.AccessMode getAccessMode()
+    {
+        return IU.AccessMode.MESSAGE;
+    }
+
 }

ipaacalib/java/src/ipaaca/OutputBuffer.java

@@ -55,7 +55,9 @@ import rsb.Informer;
 import rsb.InitializeException;
 import rsb.RSBException;
 import rsb.patterns.DataCallback;
+import rsb.patterns.EventCallback;
 import rsb.patterns.LocalServer;
+import rsb.Event;
 
 import com.google.common.collect.HashMultimap;
 import com.google.common.collect.SetMultimap;
@@ -131,48 +133,58 @@ public class OutputBuffer extends Buffer
         this.channel = ipaaca_channel;
     }
 
-    private final class RemoteUpdatePayload extends DataCallback<Integer, IUPayloadUpdate>
+    private final class RemoteUpdatePayload extends EventCallback //DataCallback<Long, IUPayloadUpdate>
     {
         @Override
-        public Integer invoke(IUPayloadUpdate data) throws Throwable
+        public Event invoke(final Event request) //throws Throwable
         {
             logger.debug("remoteUpdate");
-            return remoteUpdatePayload(data);
+            long result = remoteUpdatePayload((IUPayloadUpdate) request.getData());
+            //System.out.println("remoteUpdatePayload yielded revision "+result);
+            return new Event(Long.class, new Long(result));
         }
 
     }
+    /*private final class RemoteUpdatePayload extends DataCallback<Long, IUPayloadUpdate>
+    {
+        @Override
+        public Long invoke(IUPayloadUpdate data) throws Throwable
+        {
+            logger.debug("remoteUpdate");
+            return remoteUpdatePayload(data);
+        }
 
-    private final class RemoteUpdateLinks extends DataCallback<Integer, IULinkUpdate>
+    }*/
+
+    private final class RemoteUpdateLinks extends EventCallback // DataCallback<Long, IULinkUpdate>
     {
         @Override
-        public Integer invoke(IULinkUpdate data) throws Throwable
+        public Event invoke(final Event request) //throws Throwable
         {
             logger.debug("remoteUpdateLinks");
-            return remoteUpdateLinks(data);
+            return new Event(Long.class, new Long(remoteUpdateLinks((IULinkUpdate) request.getData())));
         }
 
     }
 
-    private final class RemoteCommit extends DataCallback<Integer, IUCommission>
+    private final class RemoteCommit extends EventCallback //DataCallback<Long, IUCommission>
     {
         @Override
-        public Integer invoke(IUCommission data) throws Throwable
+        public Event invoke(final Event request) //throws Throwable
         {
             logger.debug("remoteCommit");
-            return remoteCommit(data);
+            return new Event(Long.class, new Long(remoteCommit((IUCommission) request.getData())));
         }
-
     }
 
-    private final class RemoteResendRequest extends DataCallback<Integer, IUResendRequest>
+    private final class RemoteResendRequest extends EventCallback //DataCallback<Long, IUResendRequest>
     {
         @Override
-        public Integer invoke(IUResendRequest data) throws Throwable
+        public Event invoke(final Event request) //throws Throwable
         {
             logger.debug("remoteResendRequest");
-            return remoteResendRequest(data);
+            return new Event(Long.class, new Long(remoteResendRequest((IUResendRequest) request.getData())));
         }
-
     }
 
     // def _remote_update_payload(self, update):
@@ -199,7 +211,7 @@ public class OutputBuffer extends Buffer
      * Apply a remotely requested update to one of the stored IUs.
      * @return 0 if not updated, IU version number otherwise
      */
-    int remoteUpdatePayload(IUPayloadUpdate update)
+    long remoteUpdatePayload(IUPayloadUpdate update)
     {
         if (!iuStore.containsKey(update.getUid()))
         {
@@ -244,7 +256,7 @@ public class OutputBuffer extends Buffer
      * Apply a remotely requested update to one of the stored IUs.
      * @return 0 if not updated, IU version number otherwise
      */
-    int remoteUpdateLinks(IULinkUpdate update)
+    long remoteUpdateLinks(IULinkUpdate update)
     {
         if (!iuStore.containsKey(update.getUid()))
         {
@@ -307,7 +319,7 @@ public class OutputBuffer extends Buffer
     /**
      * Apply a remotely requested commit to one of the stored IUs.
      */
-    private int remoteCommit(IUCommission iuc)
+    private long remoteCommit(IUCommission iuc)
     {
         if (!iuStore.containsKey(iuc.getUid()))
         {
@@ -336,7 +348,7 @@ public class OutputBuffer extends Buffer
     /*
      * Resend an requested iu over the specific hidden channel. (dlw) TODO
      */
-    private int remoteResendRequest(IUResendRequest iu_resend_request_pack)
+    private long remoteResendRequest(IUResendRequest iu_resend_request_pack)
     {
         if (!iuStore.containsKey(iu_resend_request_pack.getUid()))
         {
@@ -349,7 +361,7 @@ public class OutputBuffer extends Buffer
 	    Informer<Object> informer = getInformer(iu_resend_request_pack.getHiddenScopeName());
             try
             {
-                informer.send(iu);
+                informer.publish(iu);
             }
             catch (RSBException e)
             {
@@ -404,6 +416,10 @@ public class OutputBuffer extends Buffer
         {
             throw new RuntimeException(e);
         }
+        catch (RSBException e)
+        {
+            throw new RuntimeException(e);
+        }
         return informer;
     }
 
@@ -441,7 +457,7 @@ public class OutputBuffer extends Buffer
         Informer<Object> informer = getInformer(iu.getCategory());
         try
         {
-            informer.send(iu);
+            informer.publish(iu);
         }
         catch (RSBException e)
         {
@@ -475,12 +491,12 @@ public class OutputBuffer extends Buffer
      */
     protected void sendIUCommission(AbstractIU iu, String writerName)
     {
-        IUCommission iuc = Ipaaca.IUCommission.newBuilder().setUid(iu.getUid()).setRevision(iu.getRevision())
+        IUCommission iuc = Ipaaca.IUCommission.newBuilder().setUid(iu.getUid()).setRevision((int) iu.getRevision())
                 .setWriterName(writerName == null ? iu.getOwnerName() : writerName).build();
         Informer<Object> informer = getInformer(iu.getCategory());
         try
         {
-            informer.send(iuc);
+            informer.publish(iuc);
         }
         catch (RSBException e)
         {
@@ -490,11 +506,11 @@ public class OutputBuffer extends Buffer
 
     protected void sendIURetraction(AbstractIU iu)
     {
-        IURetraction iuc = Ipaaca.IURetraction.newBuilder().setUid(iu.getUid()).setRevision(iu.getRevision()).build();
+        IURetraction iuc = Ipaaca.IURetraction.newBuilder().setUid(iu.getUid()).setRevision((int) iu.getRevision()).build();
         Informer<Object> informer = getInformer(iu.getCategory());
         try
         {
-            informer.send(iuc);
+            informer.publish(iuc);
         }
         catch (RSBException e)
         {
@@ -534,7 +550,7 @@ public class OutputBuffer extends Buffer
         Informer<Object> informer = getInformer(iu.getCategory());
         try
         {
-            informer.send(update);
+            informer.publish(update);
         }
         catch (RSBException e)
         {
@@ -547,7 +563,7 @@ public class OutputBuffer extends Buffer
         Informer<Object> informer = getInformer(iu.getCategory());
         try
         {
-            informer.send(update);
+            informer.publish(update);
         }
         catch (RSBException e)
         {

ipaacalib/java/src/ipaaca/RemoteMessageIU.java

@@ -32,6 +32,7 @@
 
 package ipaaca;
 
+import ipaaca.protobuf.Ipaaca.IU;
 import ipaaca.protobuf.Ipaaca.PayloadItem;
 
 import java.util.List;
@@ -45,6 +46,11 @@ import com.google.common.collect.SetMultimap;
 public class RemoteMessageIU extends AbstractIU
 {
 
+    public IU.AccessMode getAccessMode()
+    {
+        return IU.AccessMode.MESSAGE;
+    }
+
     public RemoteMessageIU(String uid)
     {
         super(uid);

ipaacalib/java/src/ipaaca/RemotePushIU.java

@@ -33,6 +33,7 @@
 package ipaaca;
 
 import ipaaca.protobuf.Ipaaca;
+import ipaaca.protobuf.Ipaaca.IU;
 import ipaaca.protobuf.Ipaaca.IUCommission;
 import ipaaca.protobuf.Ipaaca.IULinkUpdate;
 import ipaaca.protobuf.Ipaaca.IUPayloadUpdate;
@@ -66,6 +67,11 @@ public class RemotePushIU extends AbstractIU
     private final static Logger logger = LoggerFactory.getLogger(RemotePushIU.class.getName());
     private InputBuffer inputBuffer;
 
+    public IU.AccessMode getAccessMode()
+    {
+        return IU.AccessMode.PUSH;
+    }
+
     public InputBuffer getInputBuffer()
     {
         return inputBuffer;
@@ -104,15 +110,17 @@ public class RemotePushIU extends AbstractIU
             throw new IUReadOnlyException(this);
         }
         PayloadItem newItem = PayloadItem.newBuilder().setKey(key).setValue(value).setType("STR").build();
-        IUPayloadUpdate update = IUPayloadUpdate.newBuilder().setIsDelta(true).setUid(getUid()).setRevision(getRevision())
+        IUPayloadUpdate update = IUPayloadUpdate.newBuilder().setIsDelta(true).setUid(getUid()).setRevision((int) getRevision())
                 .setWriterName(getBuffer().getUniqueName()).addNewItems(newItem).build();
 
         RemoteServer server = getInputBuffer().getRemoteServer(this);
         logger.debug("Remote server has methods {}", server.getMethods());
-        int newRevision;
+        long newRevision;
         try
         {
-            newRevision = (Integer) server.call("updatePayload", update);
+            //System.out.println("calling remote updatePayload ...");
+            newRevision = (Long) server.call("updatePayload", update);
+            //System.out.println(" ... done");
         }
         catch (RSBException e)
         {
@@ -126,6 +134,10 @@ public class RemotePushIU extends AbstractIU
         {
             throw new RuntimeException(e);
         }
+        catch (InterruptedException e)
+        {
+            throw new RuntimeException(e);
+        }
         if (newRevision == 0)
         {
             throw new IUUpdateFailedException(this);
@@ -148,7 +160,7 @@ public class RemotePushIU extends AbstractIU
         {
             throw new IUReadOnlyException(this);
         }
-        Builder builder = IUPayloadUpdate.newBuilder().setUid(getUid()).setRevision(getRevision()).setIsDelta(true)
+        Builder builder = IUPayloadUpdate.newBuilder().setUid(getUid()).setRevision((int) getRevision()).setIsDelta(true)
                 .setWriterName(getBuffer().getUniqueName());
         for (Map.Entry<? extends String, ? extends String> item : newItems.entrySet())
         {
@@ -161,10 +173,10 @@ public class RemotePushIU extends AbstractIU
 
         RemoteServer server = getInputBuffer().getRemoteServer(this);
         logger.debug("Remote server has methods {}", server.getMethods());
-        int newRevision;
+        long newRevision;
         try
         {
-            newRevision = (Integer) server.call("updatePayload", update);
+            newRevision = (Long) server.call("updatePayload", update);
         }
         catch (RSBException e)
         {
@@ -178,6 +190,10 @@ public class RemotePushIU extends AbstractIU
         {
             throw new RuntimeException(e);
         }
+        catch (InterruptedException e)
+        {
+            throw new RuntimeException(e);
+        }
         if (newRevision == 0)
         {
             throw new IUUpdateFailedException(this);
@@ -210,13 +226,13 @@ public class RemotePushIU extends AbstractIU
         }
         else
         {
-            IUCommission iuc = Ipaaca.IUCommission.newBuilder().setUid(getUid()).setRevision(getRevision())
+            IUCommission iuc = Ipaaca.IUCommission.newBuilder().setUid(getUid()).setRevision((int) getRevision())
                     .setWriterName(getBuffer().getUniqueName()).build();
             RemoteServer server = inputBuffer.getRemoteServer(this);
-            int newRevision;
+            long newRevision;
             try
             {
-                newRevision = (Integer) server.call("commit", iuc);
+                newRevision = (Long) server.call("commit", iuc);
             }
             catch (RSBException e)
             {
@@ -230,6 +246,10 @@ public class RemotePushIU extends AbstractIU
             {
                 throw new RuntimeException(e);
             }
+            catch (InterruptedException e)
+            {
+                throw new RuntimeException(e);
+            }
             if (newRevision == 0)
             {
                 throw new IUCommittedException(this);
@@ -281,13 +301,13 @@ public class RemotePushIU extends AbstractIU
             throw new IUReadOnlyException(this);
         }
 
-        IUPayloadUpdate iuu = IUPayloadUpdate.newBuilder().setRevision(getRevision()).setIsDelta(false).setUid(getUid())
+        IUPayloadUpdate iuu = IUPayloadUpdate.newBuilder().setRevision((int) getRevision()).setIsDelta(false).setUid(getUid())
                 .addAllNewItems(newItems).setWriterName(getBuffer() != null ? getBuffer().getUniqueName() : "").build();
         RemoteServer server = inputBuffer.getRemoteServer(this);
-        int newRevision;
+        long newRevision;
         try
         {
-            newRevision = (Integer) server.call("updatePayload", iuu);
+            newRevision = (Long) server.call("updatePayload", iuu);
         }
         catch (RSBException e)
         {
@@ -301,6 +321,10 @@ public class RemotePushIU extends AbstractIU
         {
             throw new RuntimeException(e);
         }
+        catch (InterruptedException e)
+        {
+            throw new RuntimeException(e);
+        }
         if (newRevision == 0)
         {
             throw new IUUpdateFailedException(this);
@@ -399,13 +423,13 @@ public class RemotePushIU extends AbstractIU
         {
             throw new IUReadOnlyException(this);
         }
-        IUPayloadUpdate update = IUPayloadUpdate.newBuilder().setIsDelta(true).setUid(getUid()).setRevision(getRevision())
+        IUPayloadUpdate update = IUPayloadUpdate.newBuilder().setIsDelta(true).setUid(getUid()).setRevision((int) getRevision())
                 .setWriterName(getBuffer().getUniqueName()).addKeysToRemove((String) key).build();
         RemoteServer server = getInputBuffer().getRemoteServer(this);
-        int newRevision;
+        long newRevision;
         try
         {
-            newRevision = (Integer) server.call("updatePayload", update);
+            newRevision = (Long) server.call("updatePayload", update);
         }
         catch (RSBException e)
         {
@@ -419,6 +443,10 @@ public class RemotePushIU extends AbstractIU
         {
             throw new RuntimeException(e);
         }
+        catch (InterruptedException e)
+        {
+            throw new RuntimeException(e);
+        }
         if (newRevision == 0)
         {
             throw new IUUpdateFailedException(this);
@@ -455,11 +483,11 @@ public class RemotePushIU extends AbstractIU
         }
 
         IULinkUpdate update = IULinkUpdate.newBuilder().addAllLinksToRemove(removeLinkSet).addAllNewLinks(newLinkSet).setIsDelta(isDelta)
-                .setWriterName(getBuffer() != null ? getBuffer().getUniqueName() : "").setUid(getUid()).setRevision(getRevision()).build();
-        int newRevision;
+                .setWriterName(getBuffer() != null ? getBuffer().getUniqueName() : "").setUid(getUid()).setRevision((int) getRevision()).build();
+        long newRevision;
         try
         {
-            newRevision = (Integer) server.call("updateLinks", update);
+            newRevision = (Long) server.call("updateLinks", update);
         }
         catch (RSBException e)
         {
@@ -473,6 +501,10 @@ public class RemotePushIU extends AbstractIU
         {
             throw new RuntimeException(e);
         }
+        catch (InterruptedException e)
+        {
+            throw new RuntimeException(e);
+        }
         if (newRevision == 0)
         {
             throw new IUUpdateFailedException(this);

ipaacalib/java/test/src/ipaaca/ComponentPushCommunicationIntegrationTest.java

@@ -183,7 +183,7 @@ public class ComponentPushCommunicationIntegrationTest
     	payloadUpdate.put("chunk12", "item2");
     	payloadUpdate.put("chunk13", "item3");
     	payloadUpdate.put("chunk14", "item4");
-    	int oldRev = iuIn.getRevision();
+    	long oldRev = iuIn.getRevision();
     	localIU.getPayload().merge(payloadUpdate);
     	Thread.sleep(200);
     	assertEquals(oldRev + 1, iuIn.getRevision());
@@ -197,7 +197,7 @@ public class ComponentPushCommunicationIntegrationTest
     	payloadUpdate2.put("chunk22", "item6");
     	payloadUpdate2.put("chunk13", "item3-changed");
     	payloadUpdate2.put("chunk14", "item4-changed");
-    	int oldRev2 = iuIn.getRevision();
+    	long oldRev2 = iuIn.getRevision();
     	iuIn.getPayload().merge(payloadUpdate2);
     	Thread.sleep(200);
     	assertEquals(oldRev2 + 1, localIU.getRevision());

ipaacalib/java/test/src/ipaaca/InputBufferTest.java

@@ -54,7 +54,7 @@ public class InputBufferTest
         iu.setOwnerName("owner");
         iu.setReadOnly(false);
         iu.setRevision(1);
-        informer.send(iu);
+        informer.publish(iu);
         
         Thread.sleep(1000);
         AbstractIU iuIn = inBuffer.getIU("uid1");

ipaacalib/proto/ipaaca.proto

@@ -2,7 +2,7 @@
 //  "Incremental Processing Architecture
 //   for Artificial Conversational Agents".	
 //
-// Copyright (c) 2009-2014 Social Cognitive Systems Group
+// Copyright (c) 2009-2022 Social Cognitive Systems Group
 //                         CITEC, Bielefeld University	
 //
 // http://opensource.cit-ec.de/projects/ipaaca/
@@ -28,72 +28,150 @@
 // Forschungsgemeinschaft (DFG) in the context of the German
 // Excellence Initiative.
 
+syntax = "proto2";
+
 package ipaaca.protobuf;
 
+enum TransportMessageType {
+    WireTypeRESERVED = 0;
+    WireTypeIntMessage = 1;
+    WireTypeRemoteRequestResult = 2;
+    WireTypeIU = 3;
+    WireTypeMessageIU = 4; // special case on the wire (use other converter)
+    WireTypeIUPayloadUpdate = 5;
+    WireTypeIULinkUpdate = 6;
+    WireTypeIURetraction = 7;
+    WireTypeIUCommission = 8;
+    WireTypeIUResendRequest = 9;
+    WireTypeIUPayloadUpdateRequest = 100;
+    WireTypeIUCommissionRequest = 101;
+    WireTypeIULinkUpdateRequest = 102;
+}
+
+
+
+message TransportLevelWrapper {
+    required TransportMessageType transport_message_type = 1;
+    required bytes raw_message = 2;
+}
+
 message IntMessage {
-	required sint32 value = 1;
+    required sint32 value = 1;
 }
 
 message LinkSet {
-	required string type = 1;
-	repeated string targets = 2;
+    required string type = 1;
+    repeated string targets = 2;
 }
 
 message PayloadItem {
-	required string key = 1;
-	required string value = 2;
-	required string type = 3 [default = "str"];
+    required string key = 1;
+    required string value = 2;
+    required string type = 3 [default = "str"];
 }
 
 message IU {
-	enum AccessMode {
-		PUSH = 0;
-		REMOTE = 1;
-		MESSAGE = 2;
-	}
-
-	required string uid  = 1;
-	required uint32 revision = 2;
-	required string category = 3 [default = "undef"];
-	required string payload_type = 4 [default = "MAP"];
-	required string owner_name = 5;
-	required bool committed = 6 [default = false];
-	required AccessMode access_mode = 7 [default = PUSH];
-	required bool read_only = 8 [default = false];
-	repeated PayloadItem payload = 9;
-	repeated LinkSet links = 10;
+    enum AccessMode {
+        PUSH = 0;
+        REMOTE = 1;
+        MESSAGE = 2;
+    }
+
+    required string uid  = 1;
+    required uint32 revision = 2;
+    required string category = 3 [default = "undef"];
+    required string payload_type = 4 [default = "MAP"];
+    required string owner_name = 5;
+    required bool committed = 6 [default = false];
+    required AccessMode access_mode = 7 [default = PUSH];
+    required bool read_only = 8 [default = false];
+    repeated PayloadItem payload = 9;
+    repeated LinkSet links = 10;
+    optional string request_uid = 100 [default = ""];
+    optional string request_endpoint = 101 [default = ""];
 }
 
 message IUPayloadUpdate {
-	required string uid = 1;
-	required uint32 revision = 2;
-	repeated PayloadItem new_items = 3;
-	repeated string keys_to_remove = 4;
-	required bool is_delta = 5 [default = false];
-	required string writer_name = 6;
+    required string uid = 1;
+    required uint32 revision = 2;
+    repeated PayloadItem new_items = 3;
+    repeated string keys_to_remove = 4;
+    required bool is_delta = 5 [default = false];
+    required string writer_name = 6;
+    optional string request_uid = 100 [default = ""];
+    optional string request_endpoint = 101 [default = ""];
 }
 
 message IURetraction {
-	required string uid = 1;
-	required uint32 revision = 2;
+    required string uid = 1;
+    required uint32 revision = 2;
+    optional string request_uid = 100 [default = ""];
+    optional string request_endpoint = 101 [default = ""];
 }
 
 message IUCommission {
-	required string uid = 1;
-	required uint32 revision = 2;
-	required string writer_name = 3;
+    required string uid = 1;
+    required uint32 revision = 2;
+    required string writer_name = 3;
+    optional string request_uid = 100 [default = ""];
+    optional string request_endpoint = 101 [default = ""];
+}
+
+message IULinkUpdate {
+    required string uid = 1;
+    required uint32 revision = 2;
+    repeated LinkSet new_links = 3;
+    repeated LinkSet links_to_remove = 4;
+    required bool is_delta = 5 [default = false];
+    required string writer_name = 6;
+    optional string request_uid = 100 [default = ""];
+    optional string request_endpoint = 101 [default = ""];
 }
 
 message IUResendRequest {
-	required string uid = 1;
-	required string hidden_scope_name = 2;
+    required string uid = 1;
+    required string hidden_scope_name = 2;
+    optional string request_uid = 100 [default = ""];
+    optional string request_endpoint = 101 [default = ""];
 }
 
-message IULinkUpdate {
-	required string uid = 1;
-	required uint32 revision = 2;
-	repeated LinkSet new_links = 3;
-	repeated LinkSet links_to_remove = 4;
-	required bool is_delta = 5 [default = false];
-	required string writer_name = 6;
+// Result for remote operations (below).
+//  Used to send a raw int, which was problematic.
+//  Usually: 0 = Failed, >0 = new revision of successfully modified resource.
+message RemoteRequestResult {
+    required uint32 result = 1;
+    optional string request_uid = 100 [default = ""];
+    //optional string request_endpoint = 101 [default = ""];
+}
+
+// Remote / request versions of buffer setters:
+//  they just go with a dedicated ID
+message IUPayloadUpdateRequest {
+    required string uid = 1;
+    required uint32 revision = 2;
+    repeated PayloadItem new_items = 3;
+    repeated string keys_to_remove = 4;
+    required bool is_delta = 5 [default = false];
+    required string writer_name = 6;
+    optional string request_uid = 100 [default = ""];
+    optional string request_endpoint = 101 [default = ""];
 }
+message IUCommissionRequest {
+    required string uid = 1;
+    required uint32 revision = 2;
+    required string writer_name = 3;
+    optional string request_uid = 100 [default = ""];
+    optional string request_endpoint = 101 [default = ""];
+}
+
+message IULinkUpdateRequest {
+    required string uid = 1;
+    required uint32 revision = 2;
+    repeated LinkSet new_links = 3;
+    repeated LinkSet links_to_remove = 4;
+    required bool is_delta = 5 [default = false];
+    required string writer_name = 6;
+    optional string request_uid = 100 [default = ""];
+    optional string request_endpoint = 101 [default = ""];
+}
+

ipaacalib/python/ivy.xml

@@ -5,8 +5,6 @@
    </publications>
    <dependencies>
       <dependency org="google" name="protobuf-python" rev="latest.release"/>
-      <dependency org="rsb" name="rsb-python" rev="latest.release"/>
-            <dependency org="spread" name="spread" rev="latest.release"/>
    </dependencies>
 
 </ivy-module>

ipaacalib/python/setup.py

+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
+"""
+Created on Fri Sep  9 14:12:05 2016
+
+@author: jpoeppel
+"""
+
+from setuptools import setup
+
+import os
+import sys
+import subprocess
+
+from os import path as op 
+from distutils.spawn import find_executable
+from setuptools.command.build_py import build_py
+from setuptools.command.bdist_egg import bdist_egg
+from distutils.command.build import build
+from distutils.command.sdist import sdist
+
+class ProtoBuild(build_py):
+    """
+    This command automatically compiles all .proto files with `protoc` compiler
+    and places generated files near them -- i.e. in the same directory.
+    """
+
+    def find_protoc(self):
+        "Locates protoc executable"
+
+        if 'PROTOC' in os.environ and os.path.exists(os.environ['PROTOC']):
+            protoc = os.environ['PROTOC']
+        else:
+            protoc = find_executable('protoc')
+
+        if protoc is None:
+            sys.stderr.write('protoc not found. Is protobuf-compiler installed? \n'
+                             'Alternatively, you can point the PROTOC environment variable at a local version.')
+            sys.exit(1)
+
+        return protoc
+
+    def run(self):
+        #TODO determine path automaticall
+        packagedir = "../proto"
+        print("running build proto")
+        for protofile in filter(lambda x: x.endswith('.proto'), os.listdir(packagedir)):
+            source = op.join(packagedir, protofile)
+            output = source.replace('.proto', '_pb2.py')
+
+            if (not op.exists(output) or (op.getmtime(source) > op.getmtime(output))):
+                sys.stderr.write('Protobuf-compiling ' + source + '\n')
+                subprocess.check_call([self.find_protoc(), "-I={}".format(packagedir),'--python_out=./src/ipaaca', source])
+
+class BDist_egg(bdist_egg):
+    '''
+    Simple wrapper around the normal bdist_egg command to require
+    protobuf build before normal build.
+
+    .. codeauthor:: jwienke
+
+    '''
+
+    def run(self):
+        self.run_command('build_proto')
+        bdist_egg.run(self)
+
+
+class Build(build):
+    '''
+    Simple wrapper around the normal build command to require protobuf build
+    before normal build.
+
+    .. codeauthor:: jwienke
+    '''
+
+    def run(self):
+        self.run_command('build_proto')
+        build.run(self)
+
+
+class Sdist(sdist):
+    '''
+    Simple wrapper around the normal sdist command to require protobuf build
+    before generating the source distribution..
+
+    .. codeauthor:: jwienke
+    '''
+
+    def run(self):
+        # fetch the protocol before building the source distribution so that
+        # we have a cached version and each user can rebuild the protocol
+        # with his own protobuf version
+        self.run_command('build_proto')
+        sdist.run(self)
+
+
+version = "0.1.3" #TODO determine correct version! ideally from git, maybe do something similar to rsb/setup.py
+
+        
+setup(name="ipaaca",
+      version=version,
+      author="Hendrik Buschmeier, Ramin Yaghoubzadeh, Sören Klett",
+      author_email="hbuschme@uni-bielefeld.de,ryaghoubzadeh@uni-bielefeld.de,sklett@techfak.uni-bielefeld.de",
+      license='LGPLv3+',
+      url='https://opensource.cit-ec.de/projects/ipaaca',
+      install_requires=["paho-mqtt", "six", "protobuf"],
+      packages=["ipaaca", "ipaaca.util"],
+      package_dir={"ipaaca":"src/ipaaca"},  
+
+# TODO Do we want to add ipaaca_pb2.py to the egg or as separate package?
+#      data_files=[("./ipaaca", ["ipaaca_pb2.py"])],
+                  
+#      dependency_links=[
+#          'http://www.spread.org/files/'
+#          'SpreadModule-1.5spread4.tgz#egg=SpreadModule-1.5spread4'],
+
+      cmdclass ={
+                 "build_proto": ProtoBuild,
+                 "sdist": Sdist,
+                 "build": Build,
+                 "bdist_egg":BDist_egg
+                 }
+        
+      )

ipaacalib/python/src/informer.py

@@ -4,7 +4,7 @@
 #  "Incremental Processing Architecture
 #   for Artificial Conversational Agents".	
 #
-# Copyright (c) 2009-2013 Sociable Agents Group
+# Copyright (c) 2009-2022 Sociable Agents Group
 #                         CITEC, Bielefeld University	
 #
 # http://opensource.cit-ec.de/projects/ipaaca/
@@ -36,7 +36,7 @@ import ipaaca
 
 def remote_change_dumper(iu, event_type, local):
 	if local:
-		print 'remote side '+event_type+': '+str(iu)
+		print('remote side '+event_type+': '+str(iu))
 
 
 ob = ipaaca.OutputBuffer('CoolInformerOut')

ipaacalib/python/src/ipaaca/__init__.py

@@ -4,7 +4,7 @@
 #  "Incremental Processing Architecture
 #   for Artificial Conversational Agents".
 #
-# Copyright (c) 2009-2016 Social Cognitive Systems Group
+# Copyright (c) 2009-2022 Social Cognitive Systems Group
 #                         CITEC, Bielefeld University
 #
 # http://opensource.cit-ec.de/projects/ipaaca/
@@ -35,8 +35,8 @@ from __future__ import division, print_function
 import os
 import threading
 
-import rsb
-import rsb.converter
+#import rsb
+#import rsb.converter
 
 import ipaaca.ipaaca_pb2
 import ipaaca.converter
@@ -46,84 +46,77 @@ from ipaaca.iu import IU, Message, IUAccessMode, IUEventType
 from ipaaca.misc import enable_logging, IpaacaArgumentParser
 from ipaaca.payload import Payload
 
+import ipaaca.backend
 
-__RSB_INITIALIZER_LOCK = threading.Lock()
-__RSB_INITIALIZED = False
+#
+# ipaaca.exit(int_retval)
+#
+from ipaaca.buffer import atexit_cleanup_function
 
+def exit(int_retval=0):
+    '''For the time being, this function can be used to
+    circumvent any sys.exit blocks, while at the same time
+    cleaning up the buffers (e.g. retracting IUs).
 
-def initialize_ipaaca_rsb_if_needed():
-	"""Initialise rsb if not yet initialise.
+    Call once at the end of any python script (or anywhere
+    in lieu of sys.exit() / os._exit(). '''
+    print('ipaaca: cleaning up and exiting with code '+str(int_retval))
+    atexit_cleanup_function()
+    os._exit(int_retval)
 
-	   * Register own RSB onverters.
-	   * Initialise RSB from enviroment variables, rsb config file, or
-	     from default values for RSB trnasport, host, and port (via
-	     ipaaca.defaults or ipaaca.misc.IpaacaArgumentParser).
-	"""
-	global __RSB_INITIALIZED
-	with __RSB_INITIALIZER_LOCK:
-		if __RSB_INITIALIZED:
-			return
-		else:
-			rsb.converter.registerGlobalConverter(
-				ipaaca.converter.IntConverter(
-					wireSchema="int32",
-					dataType=int))
-		
-			rsb.converter.registerGlobalConverter(
-				ipaaca.converter.IUConverter(
-					wireSchema="ipaaca-iu",
-					dataType=IU))
-		
-			rsb.converter.registerGlobalConverter(
-				ipaaca.converter.MessageConverter(
-					wireSchema="ipaaca-messageiu",
-					dataType=Message))
-		
-			rsb.converter.registerGlobalConverter(
-				ipaaca.converter.IULinkUpdateConverter(
-					wireSchema="ipaaca-iu-link-update",
-					dataType=converter.IULinkUpdate))
-		
-			rsb.converter.registerGlobalConverter(
-				ipaaca.converter.IUPayloadUpdateConverter(
-					wireSchema="ipaaca-iu-payload-update",
-					dataType=converter.IUPayloadUpdate))
-		
-			rsb.converter.registerGlobalConverter(
-				rsb.converter.ProtocolBufferConverter(
-					messageClass=ipaaca.ipaaca_pb2.IUCommission))
-		
-			rsb.converter.registerGlobalConverter(
-				rsb.converter.ProtocolBufferConverter(
-					messageClass=ipaaca.ipaaca_pb2.IUResendRequest))
-		
-			rsb.converter.registerGlobalConverter(
-				rsb.converter.ProtocolBufferConverter(
-					messageClass=ipaaca.ipaaca_pb2.IURetraction))
-
-			if ipaaca.defaults.IPAACA_DEFAULT_RSB_TRANSPORT is not None:
-				if ipaaca.defaults.IPAACA_DEFAULT_RSB_TRANSPORT == 'spread':
-					os.environ['RSB_TRANSPORT_SPREAD_ENABLED'] = str(1)
-					os.environ['RSB_TRANSPORT_SOCKET_ENABLED'] = str(0)
-				elif ipaaca.defaults.IPAACA_DEFAULT_RSB_TRANSPORT == 'socket':
-					os.environ['RSB_TRANSPORT_SPREAD_ENABLED'] = str(0)
-					os.environ['RSB_TRANSPORT_SOCKET_ENABLED'] = str(1)
-					if ipaaca.defaults.IPAACA_DEFAULT_RSB_SOCKET_SERVER is not None:
-						os.environ['RSB_TRANSPORT_SOCKET_SERVER'] = str(
-							ipaaca.defaults.IPAACA_DEFAULT_RSB_SOCKET_SERVER)
+__RSB_INITIALIZER_LOCK = threading.Lock()
+__RSB_INITIALIZED = False
 
-			if ipaaca.defaults.IPAACA_DEFAULT_RSB_HOST is not None:
-				os.environ['RSB_TRANSPORT_SPREAD_HOST'] = str(
-					ipaaca.defaults.IPAACA_DEFAULT_RSB_HOST)
-				os.environ['RSB_TRANSPORT_SOCKET_HOST'] = str(
-					ipaaca.defaults.IPAACA_DEFAULT_RSB_HOST)
-			if ipaaca.defaults.IPAACA_DEFAULT_RSB_PORT is not None:
-				os.environ['RSB_TRANSPORT_SPREAD_PORT'] = str(
-						ipaaca.defaults.IPAACA_DEFAULT_RSB_PORT)
-				os.environ['RSB_TRANSPORT_SOCKET_PORT'] = str(
-						ipaaca.defaults.IPAACA_DEFAULT_RSB_PORT)
 
-			rsb.__defaultParticipantConfig = \
-					rsb.ParticipantConfig.fromDefaultSources()
+def initialize_ipaaca_rsb_if_needed():
+    """Initialise rsb if not yet initialise.
 
-			__RSB_INITIALIZED = True
+       * Register own RSB converters.
+       * Initialise RSB from enviroment variables, rsb config file, or
+         from default values for RSB trnasport, host, and port (via
+         ipaaca.defaults or ipaaca.misc.IpaacaArgumentParser).
+    """
+    global __RSB_INITIALIZED
+    with __RSB_INITIALIZER_LOCK:
+        if __RSB_INITIALIZED:
+            return
+        else:
+            ipaaca.converter.register_global_converter(
+                ipaaca.converter.IUConverter(
+                    wireSchema="ipaaca-iu",
+                    dataType=IU))
+            ipaaca.converter.register_global_converter(
+                ipaaca.converter.MessageConverter(
+                    wireSchema="ipaaca-messageiu",
+                    dataType=Message))
+            ipaaca.converter.register_global_converter(
+                ipaaca.converter.IULinkUpdateConverter(
+                    wireSchema="ipaaca-iu-link-update",
+                    dataType=converter.IULinkUpdate))
+            ipaaca.converter.register_global_converter(
+                ipaaca.converter.IUPayloadUpdateConverter(
+                    wireSchema="ipaaca-iu-payload-update",
+                    dataType=converter.IUPayloadUpdate))
+            if ipaaca.defaults.IPAACA_DEFAULT_RSB_TRANSPORT is not None:
+                if ipaaca.defaults.IPAACA_DEFAULT_RSB_TRANSPORT == 'spread':
+                    os.environ['RSB_TRANSPORT_SPREAD_ENABLED'] = str(1)
+                    os.environ['RSB_TRANSPORT_SOCKET_ENABLED'] = str(0)
+                elif ipaaca.defaults.IPAACA_DEFAULT_RSB_TRANSPORT == 'socket':
+                    os.environ['RSB_TRANSPORT_SPREAD_ENABLED'] = str(0)
+                    os.environ['RSB_TRANSPORT_SOCKET_ENABLED'] = str(1)
+                    if ipaaca.defaults.IPAACA_DEFAULT_RSB_SOCKET_SERVER is not None:
+                        os.environ['RSB_TRANSPORT_SOCKET_SERVER'] = str(
+                            ipaaca.defaults.IPAACA_DEFAULT_RSB_SOCKET_SERVER)
+            if ipaaca.defaults.IPAACA_DEFAULT_RSB_HOST is not None:
+                os.environ['RSB_TRANSPORT_SPREAD_HOST'] = str(
+                    ipaaca.defaults.IPAACA_DEFAULT_RSB_HOST)
+                os.environ['RSB_TRANSPORT_SOCKET_HOST'] = str(
+                    ipaaca.defaults.IPAACA_DEFAULT_RSB_HOST)
+            if ipaaca.defaults.IPAACA_DEFAULT_RSB_PORT is not None:
+                os.environ['RSB_TRANSPORT_SPREAD_PORT'] = str(
+                        ipaaca.defaults.IPAACA_DEFAULT_RSB_PORT)
+                os.environ['RSB_TRANSPORT_SOCKET_PORT'] = str(
+                        ipaaca.defaults.IPAACA_DEFAULT_RSB_PORT)
+            #
+            ipaaca.backend.register_backends()
+            __RSB_INITIALIZED = True

ipaacalib/python/src/ipaaca/backend.py

+# -*- coding: utf-8 -*-
+
+# This file is part of IPAACA, the
+#  "Incremental Processing Architecture
+#   for Artificial Conversational Agents".
+#
+# Copyright (c) 2009-2022 Social Cognitive Systems Group
+#                         CITEC, Bielefeld University
+#
+# http://opensource.cit-ec.de/projects/ipaaca/
+# http://purl.org/net/ipaaca
+#
+# This file may be licensed under the terms of of the
+# GNU Lesser General Public License Version 3 (the ``LGPL''),
+# or (at your option) any later version.
+#
+# Software distributed under the License is distributed
+# on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+# express or implied. See the LGPL for the specific language
+# governing rights and limitations.
+#
+# You should have received a copy of the LGPL along with this
+# program. If not, go to http://www.gnu.org/licenses/lgpl.html
+# or write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# The development of this software was supported by the
+# Excellence Cluster EXC 277 Cognitive Interaction Technology.
+# The Excellence Cluster EXC 277 is a grant of the Deutsche
+# Forschungsgemeinschaft (DFG) in the context of the German
+# Excellence Initiative.
+
+from __future__ import division, print_function
+
+import ipaaca.defaults
+import ipaaca.exception
+import ipaaca.iu
+import ipaaca.misc
+import ipaaca.converter
+
+import threading
+import uuid
+import os
+import time
+
+LOGGER = ipaaca.misc.get_library_logger()
+
+__registered_backends = {}
+__backend_registration_done = False
+
+def register_backends():
+    global __registered_backends
+    global __backend_registration_done
+    if not __backend_registration_done:
+        __backend_registration_done = True
+        LOGGER.debug('Registering available back-ends')
+        # register available backends
+        # mqtt
+        import ipaaca.backend_mqtt
+        be = ipaaca.backend_mqtt.create_backend()
+        if be is not None:
+            __registered_backends[be.name] = be
+            LOGGER.debug('Back-end '+str(be.name)+' added')
+
+        # ros
+        import ipaaca.backend_ros
+        be = ipaaca.backend_ros.create_backend()
+        if be is not None:
+            __registered_backends[be.name] = be
+            LOGGER.debug('Back-end '+str(be.name)+' added')
+
+def get_default_backend():
+    # TODO selection mechanism / config
+    if not __backend_registration_done:
+        register_backends()
+    if len(__registered_backends) == 0:
+        raise RuntimeError('No back-ends could be initialized for ipaaca-python')
+    cfg = ipaaca.config.get_global_config()
+    preferred = cfg.get_with_default('backend', None)
+    if preferred is None:
+        k = list(__registered_backends.keys())[0]
+        if len(__registered_backends) > 1:
+            LOGGER.warning('No preferred ipaaca.backend set, returning one of several (probably the first in list)')
+            print('Using randomly selected back-end {}!'.format(k))
+    else:
+        if preferred in __registered_backends:
+            k = preferred
+        else:
+            raise ipaaca.exception.BackendInitializationError(preferred)
+    LOGGER.info('Back-end is '+str(k))
+    return __registered_backends[k]
+
+

ipaacalib/python/src/ipaaca/backend_mqtt.py

+# -*- coding: utf-8 -*-
+
+# This file is part of IPAACA, the
+#  "Incremental Processing Architecture
+#   for Artificial Conversational Agents".
+#
+# Copyright (c) 2009-2022 Social Cognitive Systems Group
+#                         CITEC, Bielefeld University
+#
+# http://opensource.cit-ec.de/projects/ipaaca/
+# http://purl.org/net/ipaaca
+#
+# This file may be licensed under the terms of of the
+# GNU Lesser General Public License Version 3 (the ``LGPL''),
+# or (at your option) any later version.
+#
+# Software distributed under the License is distributed
+# on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+# express or implied. See the LGPL for the specific language
+# governing rights and limitations.
+#
+# You should have received a copy of the LGPL along with this
+# program. If not, go to http://www.gnu.org/licenses/lgpl.html
+# or write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# The development of this software was supported by the
+# Excellence Cluster EXC 277 Cognitive Interaction Technology.
+# The Excellence Cluster EXC 277 is a grant of the Deutsche
+# Forschungsgemeinschaft (DFG) in the context of the German
+# Excellence Initiative.
+
+from __future__ import division, print_function
+
+import collections
+
+import ipaaca.ipaaca_pb2
+import ipaaca.defaults
+import ipaaca.exception
+import ipaaca.iu
+import ipaaca.misc
+import ipaaca.converter
+import ipaaca.backend
+import ipaaca.config
+
+import threading
+try:
+    import queue
+except:
+    import Queue as queue
+import uuid
+import os
+import time
+
+try:
+    import paho.mqtt.client as mqtt
+    MQTT_ENABLED = True
+except:
+    MQTT_ENABLED = False
+
+if not MQTT_ENABLED:
+    def create_backend():
+        return None
+else:
+    def create_backend():
+        return MQTTBackend(name='mqtt')
+    
+    LOGGER = ipaaca.misc.get_library_logger()
+
+    _REMOTE_SERVER_MAX_QUEUED_REQUESTS = -1 # unlimited
+    _REMOTE_LISTENER_MAX_QUEUED_EVENTS = 1024 # 'Full' exception if exceeded
+
+    class EventWrapper(object):
+        def __init__(self, data):
+            self.data = data
+
+    class PendingRequest(object):
+        '''Encapsulation of a pending remote request with
+        a facility to keep the requesting thread locked
+        until the reply or a timeout unlocks it.'''
+        def __init__(self, request):
+            self._request = request
+            self._event = threading.Event()
+            self._reply = None
+            self._request_uid = str(uuid.uuid4())[0:8]
+        def wait_for_reply(self, timeout=30.0):
+            wr = self._event.wait(timeout)
+            return None if wr is False else self._reply
+        def reply_with_result(self, reply):
+            self._reply = reply
+            self._event.set()
+            
+    class Informer(object):
+        '''Informer interface, wrapping an outbound port to MQTT'''
+        def __init__(self, scope, config=None):
+            self._scope = scope
+            self._running = False
+            self._live = False
+            self._live_event = threading.Event()
+            self._handlers = []
+            #
+            self._client_id = '%s.%s_%s'%(self.__module__, self.__class__.__name__, str(uuid.uuid4())[0:8])
+            self._client_id += '_' + scope
+            self._mqtt_client = mqtt.Client(self._client_id)
+            self._host = config.get_with_default('transport.mqtt.host', 'localhost', warn=True)
+            self._port = int(config.get_with_default('transport.mqtt.port', 1883, warn=True))
+            self._mqtt_client.on_connect = self.mqtt_callback_on_connect
+            self._mqtt_client.on_disconnect = self.mqtt_callback_on_disconnect
+            self._mqtt_client.on_message = self.mqtt_callback_on_message
+            self._mqtt_client.on_subscribe = self.mqtt_callback_on_subscribe
+            #self._mqtt_client.on_publish = self.mqtt_callback_on_publish
+            self.run_in_background()
+        def deactivate(self):
+            pass
+        def deactivate_internal(self):
+            self._mqtt_client.disconnect()
+            self._mqtt_client = None
+        def run_in_background(self):
+            if not self._running:
+                self._running = True
+                self._mqtt_client.loop_start()
+                self._mqtt_client.connect(self._host, self._port)
+        def mqtt_callback_on_connect(self, client, userdata, flags, rc):
+            if rc > 0:
+                LOGGER.warning('MQTT connect failed, result code ' + str(rc))
+            else:
+                self._live = True
+                self._live_event.set()
+        def mqtt_callback_on_subscribe(self, client, userdata, mid, granted_qos):
+            # TODO should / could track how many / which topics have been granted
+            if any(q != 2 for q in granted_qos):
+                LOGGER.warning('MQTT subscription did not obtain QoS level 2')
+        def mqtt_callback_on_disconnect(self, client, userdata, rc):
+            LOGGER.warning('MQTT disconnect for '+str(self._scope)+' with result code '+str(rc))
+        def mqtt_callback_on_message(self, client, userdata, message):
+            pass
+        def publishData(self, data):
+            #print('Informer publishing '+str(data.__class__.__name__)+' on '+self._scope)
+            self._mqtt_client.publish(self._scope, ipaaca.converter.serialize(data), qos=2)
+
+    class BackgroundEventDispatcher(threading.Thread):
+        def __init__(self, listener):
+            super(BackgroundEventDispatcher, self).__init__()
+            self.daemon = True
+            self._listener = listener
+        def terminate(self):
+            self._running = False
+        def run(self):
+            self._running = True
+            listener = self._listener
+            while self._running: # auto-terminated (daemon)
+                event = listener._event_queue.get(block=True, timeout=None)
+                if event is None: return # signaled termination
+                #print('\033[31mDispatch '+str(event.data.__class__.__name__)+' start ...\033[m')
+                for handler in self._listener._handlers:
+                    handler(event)
+                #print('\033[32m... dispatch '+str(event.data.__class__.__name__)+' end.\033[m')
+
+    class Listener(object):
+        '''Listener interface, wrapping an inbound port from MQTT'''
+        def __init__(self, scope, config=None):
+            self._scope = scope
+            self._running = False
+            self._live = False
+            self._live_event = threading.Event()
+            self._handlers = []
+            self._event_queue = queue.Queue(_REMOTE_LISTENER_MAX_QUEUED_EVENTS)
+            #
+            self._client_id = '%s.%s_%s'%(self.__module__, self.__class__.__name__, str(uuid.uuid4())[0:8])
+            self._client_id += '_' + scope
+            self._mqtt_client = mqtt.Client(self._client_id)
+            self._host = config.get_with_default('transport.mqtt.host', 'localhost', warn=True)
+            self._port = int(config.get_with_default('transport.mqtt.port', 1883, warn=True))
+            self._mqtt_client.on_connect = self.mqtt_callback_on_connect
+            self._mqtt_client.on_disconnect = self.mqtt_callback_on_disconnect
+            self._mqtt_client.on_message = self.mqtt_callback_on_message
+            self._mqtt_client.on_subscribe = self.mqtt_callback_on_subscribe
+            #self._mqtt_client.on_socket_open = self.mqtt_callback_on_socket_open
+            #self._mqtt_client.on_socket_close = self.mqtt_callback_on_socket_close
+            #self._mqtt_client.on_log = self.mqtt_callback_on_log
+            #self._mqtt_client.on_publish = self.mqtt_callback_on_publish
+            self._dispatcher = BackgroundEventDispatcher(self)
+            self._dispatcher.start()
+            self.run_in_background()
+        def deactivate(self):
+            pass
+        def deactivate_internal(self):
+            self._event_queue.put(None, block=False) # signal termination, waking queue
+            self._dispatcher.terminate()
+            self._mqtt_client.disconnect()
+            self._mqtt_client = None
+        def run_in_background(self):
+            if not self._running:
+                self._running = True
+                self._mqtt_client.loop_start()
+                LOGGER.debug('Connect to '+str(self._host)+':'+str(self._port))
+                self._mqtt_client.connect(self._host, self._port)
+        #def mqtt_callback_on_log(self, client, userdata, level, buf):
+        #    print('Listener: LOG: '+str(buf))
+        def mqtt_callback_on_connect(self, client, userdata, flags, rc):
+            if rc > 0:
+                LOGGER.warning('MQTT connect failed, result code ' + str(rc))
+            else:
+                self._mqtt_client.subscribe(self._scope, qos=2)
+        def mqtt_callback_on_subscribe(self, client, userdata, mid, granted_qos):
+            # TODO should / could track how many / which topics have been granted
+            if any(q != 2 for q in granted_qos):
+                LOGGER.warning('MQTT subscription did not obtain QoS level 2')
+            self._live = True
+            self._live_event.set()
+        def mqtt_callback_on_disconnect(self, client, userdata, rc):
+            LOGGER.warning('MQTT disconnect for '+str(self._scope)+' with result code '+str(rc))
+        def mqtt_callback_on_message(self, client, userdata, message):
+            event = EventWrapper(ipaaca.converter.deserialize(message.payload))
+            self._event_queue.put(event, block=False) # queue event for BackgroundEventDispatcher
+        def addHandler(self, handler):
+            self._handlers.append(handler)
+        #def publishData(self, data):
+        #    self._mqtt_client.publish(self._
+
+    class LocalServer(object):
+        '''LocalServer interface, allowing for RPC requests to
+        IU functions, or reporting back success or failure.'''
+        def __init__(self, buffer_impl, scope, config=None):
+            self._buffer = buffer_impl
+            self._scope = scope
+            self._running = False
+            self._live = False
+            self._live_event = threading.Event()
+            self._pending_requests_lock = threading.Lock()
+            self._pending_requests = {}
+            self._uuid = str(uuid.uuid4())[0:8]
+            self._name = 'PID_' + str(os.getpid()) + '_LocalServer_' + self._uuid # unused atm
+            #
+            self._client_id = '%s.%s_%s'%(self.__module__, self.__class__.__name__, str(uuid.uuid4())[0:8])
+            self._client_id += '_' + scope
+            self._mqtt_client = mqtt.Client(self._client_id)
+            self._host = config.get_with_default('transport.mqtt.host', 'localhost', warn=True)
+            self._port = int(config.get_with_default('transport.mqtt.port', 1883, warn=True))
+            self._mqtt_client.on_connect = self.mqtt_callback_on_connect
+            self._mqtt_client.on_disconnect = self.mqtt_callback_on_disconnect
+            self._mqtt_client.on_message = self.mqtt_callback_on_message
+            self._mqtt_client.on_subscribe = self.mqtt_callback_on_subscribe
+            #self._mqtt_client.on_publish = self.mqtt_callback_on_publish
+            self.run_in_background()
+        def deactivate(self):
+            pass
+        def deactivate_internal(self):
+            self._mqtt_client.disconnect()
+            self._mqtt_client = None
+        def run_in_background(self):
+            if not self._running:
+                self._running = True
+                self._mqtt_client.loop_start()
+                self._mqtt_client.connect(self._host, self._port)
+        def mqtt_callback_on_connect(self, client, userdata, flags, rc):
+            if rc > 0:
+                LOGGER.warning('MQTT connect failed, result code ' + str(rc))
+            else:
+                self._mqtt_client.subscribe(self._scope, qos=2)
+        def mqtt_callback_on_subscribe(self, client, userdata, mid, granted_qos):
+            # TODO should / could track how many / which topics have been granted
+            if any(q != 2 for q in granted_qos):
+                LOGGER.warning('MQTT subscription did not obtain QoS level 2')
+            self._live = True
+            self._live_event.set()
+        def mqtt_callback_on_disconnect(self, client, userdata, rc):
+            LOGGER.warning('MQTT disconnect for '+str(self._scope)+' with result code '+str(rc))
+        def mqtt_callback_on_message(self, client, userdata, message):
+            req = ipaaca.converter.deserialize(message.payload)
+            result = None
+            if isinstance(req, ipaaca.converter.IUPayloadUpdate):
+                result = self.attempt_to_apply_remote_updatePayload(req)
+            elif isinstance(req, ipaaca.converter.IULinkUpdate):
+                result = self.attempt_to_apply_remote_updateLinks(req)
+            elif isinstance(req, ipaaca.ipaaca_pb2.IUCommission):
+                result = self.attempt_to_apply_remote_commit(req)
+            elif isinstance(req, ipaaca.ipaaca_pb2.IUResendRequest):
+                result = self.attempt_to_apply_remote_resendRequest(req)
+            else:
+                raise RuntimeError('LocalServer: got an object of wrong class '+str(req.__class__.__name__))  # TODO replace
+            if result is not None:
+                self.send_result_for_request(req, result)
+        #
+        def send_result_for_request(self, obj, result):
+            pbo = ipaaca.ipaaca_pb2.RemoteRequestResult()
+            pbo.result = result
+            pbo.request_uid = obj.request_uid
+            #print('Sending result to endpoint '+str(obj.request_endpoint))
+            self._mqtt_client.publish(obj.request_endpoint, ipaaca.converter.serialize(pbo), qos=2)
+        def attempt_to_apply_remote_updateLinks(self, obj):
+            return self._buffer._remote_update_links(obj)
+        def attempt_to_apply_remote_updatePayload(self, obj):
+            return self._buffer._remote_update_payload(obj)
+        def attempt_to_apply_remote_commit(self, obj):
+            return self._buffer._remote_commit(obj)
+        def attempt_to_apply_remote_resendRequest(self, obj):
+            return self._buffer._remote_request_resend(obj)
+
+
+    class RemoteServer(object):
+        '''RemoteServer, connects to a LocalServer on the side
+        of an actual IU owner, which will process any requests.
+        The RemoteServer is put on hold while the owner is
+        processing. RemoteServer is from RSB terminology,
+        it might more aptly be described as an RPC client.'''
+        def __init__(self, remote_end_scope, config=None):
+            self._running = False
+            self._live = False
+            self._live_event = threading.Event()
+            self._pending_requests_lock = threading.Lock()
+            self._pending_requests = {}
+            #queue.Queue(_REMOTE_SERVER_MAX_QUEUED_REQUESTS)
+            self._uuid = str(uuid.uuid4())[0:8]
+            self._name = 'PID_' + str(os.getpid()) + '_RemoteServer_' + self._uuid
+            # will RECV here:
+            self._scope = '/ipaaca/remotes/' + self._name
+            # will SEND here
+            self._remote_end_scope = remote_end_scope
+            #
+            self._client_id = '%s.%s_%s'%(self.__module__, self.__class__.__name__, str(uuid.uuid4())[0:8])
+            self._client_id += '_' + remote_end_scope
+            self._mqtt_client = mqtt.Client(self._client_id)
+            self._host = config.get_with_default('transport.mqtt.host', 'localhost', warn=True)
+            self._port = int(config.get_with_default('transport.mqtt.port', 1883, warn=True))
+            self._mqtt_client.on_connect = self.mqtt_callback_on_connect
+            self._mqtt_client.on_disconnect = self.mqtt_callback_on_disconnect
+            self._mqtt_client.on_message = self.mqtt_callback_on_message
+            self._mqtt_client.on_subscribe = self.mqtt_callback_on_subscribe
+            #self._mqtt_client.on_publish = self.mqtt_callback_on_publish
+            self.run_in_background()
+        def deactivate(self):
+            pass
+        def deactivate_internal(self):
+            self._mqtt_client.disconnect()
+            self._mqtt_client = None
+        def run_in_background(self):
+            if not self._running:
+                self._running = True
+                self._mqtt_client.loop_start()
+                self._mqtt_client.connect(self._host, self._port)
+        def mqtt_callback_on_connect(self, client, userdata, flags, rc):
+            if rc > 0:
+                LOGGER.warning('MQTT connect failed, result code ' + str(rc))
+            else:
+                self._mqtt_client.subscribe(self._scope, qos=2)
+        def mqtt_callback_on_subscribe(self, client, userdata, mid, granted_qos):
+            # TODO should / could track how many / which topics have been granted
+            if any(q != 2 for q in granted_qos):
+                LOGGER.warning('MQTT subscription did not obtain QoS level 2')
+            self._live = True
+            self._live_event.set()
+        def mqtt_callback_on_disconnect(self, client, userdata, rc):
+            LOGGER.warning('MQTT disconnect for '+str(self._scope)+' with result code '+str(rc))
+        def mqtt_callback_on_message(self, client, userdata, message):
+            reply = ipaaca.converter.deserialize(message.payload)
+            if isinstance(reply, ipaaca.ipaaca_pb2.RemoteRequestResult):
+                uid = reply.request_uid
+                pending_request = None
+                with self._pending_requests_lock:
+                    if uid in self._pending_requests:
+                        pending_request = self._pending_requests[uid]
+                        del self._pending_requests[uid]
+                if pending_request is None:
+                    raise RuntimeError('RemoteServer: got a reply for request uid that is not queued: '+str(uid))
+                else:
+                    # provide result to other thread and unblock it
+                    pending_request.reply_with_result(reply)
+            else:
+                raise RuntimeError('RemoteServer: got an object of wrong class '+str(reply.__class__.__name__))  # TODO replace
+        def queue_pending_request(self, request):
+            pending_request = PendingRequest(request)
+            with self._pending_requests_lock:
+                if _REMOTE_SERVER_MAX_QUEUED_REQUESTS>0 and len(self._pending_requests) >= _REMOTE_SERVER_MAX_QUEUED_REQUESTS:
+                    raise RuntimeError('RemoteServer: maximum number of pending requests exceeded')   # TODO replace?
+                else:
+                    self._pending_requests[pending_request._request_uid] = pending_request
+                    return pending_request
+        # impl
+        def blocking_call(self, request):
+            # Broker's queue will raise before sending anything if capacity is exceeded
+            pending_request = self.queue_pending_request(request)
+            # complete and send request
+            request.request_uid = pending_request._request_uid
+            request.request_endpoint = self._scope
+            self._mqtt_client.publish(self._remote_end_scope, ipaaca.converter.serialize(request), qos=2)
+            # wait for other end to return result
+            reply = pending_request.wait_for_reply()
+            if reply is None:
+                LOGGER.warning('A request timed out!')
+                return 0
+            else:
+                return reply.result  # the actual int result
+        # glue that quacks like the RSB version
+        def resendRequest(self, req):
+            return self.blocking_call(req)
+        def commit(self, req):
+            return self.blocking_call(req)
+        def updatePayload(self, req):
+            return self.blocking_call(req)
+        def updateLinks(self, req):
+            return self.blocking_call(req)
+
+    class MQTTBackend(object):
+        
+        def __init__(self, name='mqtt'):
+            # back-end initialization code
+            self._config = ipaaca.config.get_global_config()
+            self._name = name
+            self._participants = set()
+
+        def _get_name(self):
+            return self._name
+        name = property(_get_name)
+
+        def teardown(self):
+            LOGGER.info('MQTT teardown: waiting 1 sec for final deliveries')
+            time.sleep(1)
+            for p in self._participants:
+                p.deactivate_internal()
+
+        def Scope(self, scope_str):
+            '''Scope adapter (glue replacing rsb.Scope)'''
+            return str(scope_str)
+
+        def createLocalServer(self, buffer_impl, scope, config=None):
+            LOGGER.debug('Creating a LocalServer on '+str(scope))
+            s = LocalServer(buffer_impl, scope, self._config if config is None else config)
+            self._participants.add(s)
+            s._live_event.wait(30.0)
+            return s
+         
+        def createRemoteServer(self, scope, config=None):
+            LOGGER.debug('Creating a RemoteServer on '+str(scope))
+            s = RemoteServer(scope, self._config if config is None else config)
+            self._participants.add(s)
+            s._live_event.wait(30.0)
+            return s
+
+        def createInformer(self, scope, config=None, dataType="ignored in this backend"):
+            LOGGER.debug('Creating an Informer on '+str(scope))
+            s = Informer(scope, self._config if config is None else config)
+            self._participants.add(s)
+            s._live_event.wait(30.0)
+            return s
+
+        def createListener(self, scope, config=None):
+            LOGGER.debug('Creating a Listener on '+str(scope))
+            s = Listener(scope, self._config if config is None else config)
+            self._participants.add(s)
+            s._live_event.wait(30.0)
+            return s
+            
+
+

ipaacalib/python/src/ipaaca/backend_ros.py

+# -*- coding: utf-8 -*-
+
+# This file is part of IPAACA, the
+#  "Incremental Processing Architecture
+#   for Artificial Conversational Agents".
+#
+# Copyright (c) 2009-2022 Social Cognitive Systems Group
+#                         CITEC, Bielefeld University
+#
+# http://opensource.cit-ec.de/projects/ipaaca/
+# http://purl.org/net/ipaaca
+#
+# This file may be licensed under the terms of of the
+# GNU Lesser General Public License Version 3 (the ``LGPL''),
+# or (at your option) any later version.
+#
+# Software distributed under the License is distributed
+# on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+# express or implied. See the LGPL for the specific language
+# governing rights and limitations.
+#
+# You should have received a copy of the LGPL along with this
+# program. If not, go to http://www.gnu.org/licenses/lgpl.html
+# or write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# The development of this software was supported by the
+# Excellence Cluster EXC 277 Cognitive Interaction Technology.
+# The Excellence Cluster EXC 277 is a grant of the Deutsche
+# Forschungsgemeinschaft (DFG) in the context of the German
+# Excellence Initiative.
+
+from __future__ import division, print_function
+
+import collections
+import sys
+
+import ipaaca.ipaaca_pb2
+import ipaaca.defaults
+import ipaaca.exception
+import ipaaca.iu
+import ipaaca.misc
+import ipaaca.converter
+import ipaaca.backend
+
+import ipaaca.config as config
+
+LOGGER = ipaaca.misc.get_library_logger()
+
+
+
+ROS_ENABLED, __try_guessing = False, False
+try:
+    import rospy
+    from std_msgs.msg import String
+    import base64
+    ROS_ENABLED = True
+except:
+    LOGGER.debug('rospy or deps not found, ROS backend disabled')
+    ROS_ENABLED = False
+
+if not ROS_ENABLED:
+    def create_backend():
+        return None
+else:
+    def create_backend():
+        return ROSBackend(name='ros')
+
+    import threading
+    try:
+        import queue
+    except:
+        import Queue as queue
+    import uuid
+    import os
+    import time
+    import sys
+
+    class EventWrapper(object):
+        def __init__(self, data):
+            self.data = data
+
+    class PendingRequest(object):
+        '''Encapsulation of a pending remote request with
+        a facility to keep the requesting thread locked
+        until the reply or a timeout unlocks it.'''
+        def __init__(self, request):
+            self._request = request
+            self._event = threading.Event()
+            self._reply = None
+            self._request_uid = str(uuid.uuid4())[0:8]
+        def wait_for_reply(self, timeout=30.0):
+            wr = self._event.wait(timeout)
+            return None if wr is False else self._reply
+        def reply_with_result(self, reply):
+            self._reply = reply
+            self._event.set()
+            
+    class Informer(object):
+        '''Informer interface, wrapping an outbound port to ROS'''
+        def __init__(self, scope, config=None):
+            self._scope = scope
+            self._running = False
+            self._live = False
+            self._live_event = threading.Event()
+            self._handlers = []
+            #
+            self._client_id = '%s.%s_%s'%(self.__module__, self.__class__.__name__, str(uuid.uuid4())[0:8])
+            self._client_id += '_' + scope
+            self._ros_pub = rospy.Publisher(self._scope, String, queue_size=100, tcp_nodelay=True, latch=True)
+            self._host = config.get_with_default('transport.mqtt.host', 'localhost', warn=True)
+            self._port = config.get_with_default('transport.mqtt.port', 1883, warn=True)
+        def deactivate(self):
+            pass
+            #self._ros_pub.unregister()
+            #self._ros_pub = None
+        def publishData(self, data):
+            self._ros_pub.publish(ROSBackend.serialize(data))
+
+    class BackgroundEventDispatcher(threading.Thread):
+        def __init__(self, event, handlers):
+            super(BackgroundEventDispatcher, self).__init__()
+            self.daemon = True
+            self._event = event
+            self._handlers = handlers
+        def run(self):
+            for handler in self._handlers:
+                handler(self._event)
+
+    class Listener(object):
+        '''Listener interface, wrapping an inbound port from ROS'''
+        def __init__(self, scope, config=None):
+            self._scope = scope
+            self._running = False
+            self._live = False
+            self._live_event = threading.Event()
+            self._handlers = []
+            #
+            self._client_id = '%s.%s_%s'%(self.__module__, self.__class__.__name__, str(uuid.uuid4())[0:8])
+            self._client_id += '_' + scope
+            self._ros_sub = rospy.Subscriber(self._scope, String, self.on_message, tcp_nodelay=True)
+            self._host = config.get_with_default('transport.mqtt.host', 'localhost', warn=True)
+            self._port = config.get_with_default('transport.mqtt.port', 1883, warn=True)
+        def deactivate(self):
+            pass
+            #self._ros_sub.unregister()
+            #self._ros_sub = None
+        def on_message(self, message):
+            event = EventWrapper(ROSBackend.deserialize(message.data))
+            ## (1) with extra thread:
+            #dispatcher = BackgroundEventDispatcher(event, self._handlers)
+            #dispatcher.start()
+            ## or (2) with no extra thread:
+            for handler in self._handlers:
+                handler(event)
+        def addHandler(self, handler):
+            self._handlers.append(handler)
+
+    class LocalServer(object):
+        '''LocalServer interface, allowing for RPC requests to
+        IU functions, or reporting back success or failure.'''
+        def __init__(self, buffer_impl, scope, config=None):
+            self._buffer = buffer_impl
+            self._scope = scope
+            self._running = False
+            self._live = False
+            self._live_event = threading.Event()
+            self._pending_requests_lock = threading.Lock()
+            self._pending_requests = {}
+            self._uuid = str(uuid.uuid4())[0:8]
+            self._name = 'PID_' + str(os.getpid()) + '_LocalServer_' + self._uuid # unused atm
+            #
+            self._client_id = '%s.%s_%s'%(self.__module__, self.__class__.__name__, str(uuid.uuid4())[0:8])
+            self._client_id += '_' + scope
+            self._ros_pubs = {}
+            self._ros_sub = rospy.Subscriber(self._scope, String, self.on_message, tcp_nodelay=True)
+            self._host = config.get_with_default('transport.mqtt.host', 'localhost', warn=True)
+            self._port = config.get_with_default('transport.mqtt.port', 1883, warn=True)
+        def get_publisher(self, endpoint):
+            if endpoint in self._ros_pubs:
+                return self._ros_pubs[endpoint]
+            else:
+                p = rospy.Publisher(endpoint, String, queue_size=10, tcp_nodelay=True, latch=True)
+                self._ros_pubs[endpoint] = p
+                return p
+        def deactivate(self):
+            pass
+            #self._ros_sub.unregister()
+            #for v in self._ros_pubs.values():
+            #    v.unregister()
+            #self._ros_sub = None
+            #self._ros_pubs = {}
+        def on_message(self, message):
+            req = ROSBackend.deserialize(message.data)
+            result = None
+            if isinstance(req, ipaaca.converter.IUPayloadUpdate):
+                result = self.attempt_to_apply_remote_updatePayload(req)
+            elif isinstance(req, ipaaca.converter.IULinkUpdate):
+                result = self.attempt_to_apply_remote_updateLinks(req)
+            elif isinstance(req, ipaaca.ipaaca_pb2.IUCommission):
+                result = self.attempt_to_apply_remote_commit(req)
+            elif isinstance(req, ipaaca.ipaaca_pb2.IUResendRequest):
+                result = self.attempt_to_apply_remote_resendRequest(req)
+            else:
+                raise RuntimeError('LocalServer: got an object of wrong class '+str(req.__class__.__name__))  # TODO replace
+            if result is not None:
+                self.send_result_for_request(req, result)
+        #
+        def send_result_for_request(self, obj, result):
+            pbo = ipaaca.ipaaca_pb2.RemoteRequestResult()
+            pbo.result = result
+            pbo.request_uid = obj.request_uid
+            #print('Sending result to endpoint '+str(obj.request_endpoint))
+            pub = self.get_publisher(obj.request_endpoint)
+            pub.publish(ROSBackend.serialize(pbo))
+        def attempt_to_apply_remote_updateLinks(self, obj):
+            return self._buffer._remote_update_links(obj)
+        def attempt_to_apply_remote_updatePayload(self, obj):
+            return self._buffer._remote_update_payload(obj)
+        def attempt_to_apply_remote_commit(self, obj):
+            return self._buffer._remote_commit(obj)
+        def attempt_to_apply_remote_resendRequest(self, obj):
+            return self._buffer._remote_request_resend(obj)
+
+
+    _REMOTE_SERVER_MAX_QUEUED_REQUESTS = -1 # unlimited
+
+    class RemoteServer(object):
+        '''RemoteServer, connects to a LocalServer on the side
+        of an actual IU owner, which will process any requests.
+        The RemoteServer is put on hold while the owner is
+        processing. RemoteServer is from RSB terminology,
+        it might more aptly be described as an RPC client.'''
+        def __init__(self, remote_end_scope, config=None):
+            self._running = False
+            self._live = False
+            self._live_event = threading.Event()
+            self._pending_requests_lock = threading.Lock()
+            self._pending_requests = {}
+            #queue.Queue(_REMOTE_SERVER_MAX_QUEUED_REQUESTS)
+            self._uuid = str(uuid.uuid4())[0:8]
+            self._name = 'PID_' + str(os.getpid()) + '_RemoteServer_' + self._uuid
+            # will RECV here:
+            self._scope = '/ipaaca/remotes/' + self._name
+            # will SEND here
+            self._remote_end_scope = remote_end_scope
+            #
+            self._client_id = '%s.%s_%s'%(self.__module__, self.__class__.__name__, str(uuid.uuid4())[0:8])
+            self._client_id += '_' + remote_end_scope
+            self._ros_pub = rospy.Publisher(self._remote_end_scope, String, queue_size=10, tcp_nodelay=True, latch=True)
+            self._ros_sub = rospy.Subscriber(self._scope, String, self.on_message, tcp_nodelay=True)
+            self._host = config.get_with_default('transport.mqtt.host', 'localhost', warn=True)
+            self._port = config.get_with_default('transport.mqtt.port', 1883, warn=True)
+        def deactivate(self):
+            pass
+            #self._ros_sub.unregister()
+            #self._ros_pub.unregister()
+            #self._ros_sub = None
+            #self._ros_pub = None
+        def on_message(self, message):
+            reply = ROSBackend.deserialize(message.data)
+            if isinstance(reply, ipaaca.ipaaca_pb2.RemoteRequestResult):
+                uid = reply.request_uid
+                pending_request = None
+                with self._pending_requests_lock:
+                    if uid in self._pending_requests:
+                        pending_request = self._pending_requests[uid]
+                        del self._pending_requests[uid]
+                if pending_request is None:
+                    raise RuntimeError('RemoteServer: got a reply for request uid that is not queued: '+str(uid))
+                else:
+                    # provide result to other thread and unblock it
+                    pending_request.reply_with_result(reply)
+            else:
+                raise RuntimeError('RemoteServer: got an object of wrong class '+str(reply.__class__.__name__))  # TODO replace
+        def queue_pending_request(self, request):
+            pending_request = PendingRequest(request)
+            with self._pending_requests_lock:
+                if _REMOTE_SERVER_MAX_QUEUED_REQUESTS>0 and len(self._pending_requests) >= _REMOTE_SERVER_MAX_QUEUED_REQUESTS:
+                    raise RuntimeError('RemoteServer: maximum number of pending requests exceeded')   # TODO replace?
+                else:
+                    self._pending_requests[pending_request._request_uid] = pending_request
+                    return pending_request
+        # impl
+        def blocking_call(self, request):
+            # Broker's queue will raise before sending anything if capacity is exceeded
+            pending_request = self.queue_pending_request(request)
+            # complete and send request
+            request.request_uid = pending_request._request_uid
+            request.request_endpoint = self._scope
+            self._ros_pub.publish(ROSBackend.serialize(request))
+            # wait for other end to return result
+            reply = pending_request.wait_for_reply()
+            if reply is None:
+                LOGGER.warning('A request timed out!')
+                return 0
+            else:
+                return reply.result  # the actual int result
+        # glue that quacks like the RSB version
+        def resendRequest(self, req):
+            return self.blocking_call(req)
+        def commit(self, req):
+            return self.blocking_call(req)
+        def updatePayload(self, req):
+            return self.blocking_call(req)
+        def updateLinks(self, req):
+            return self.blocking_call(req)
+
+    class ROSBackend(object):
+        
+        def __init__(self, name='ros'):
+            #import logging
+            # back-end initialization code
+            self._name = name
+            self._need_init = True
+            #logging.basicConfig(level=logging.DEBUG)
+        
+        def init_once(self):
+            '''Actual back-end initialization is only done when it is used'''
+            if self._need_init:
+                self._need_init = False
+                self._config = config.get_global_config()
+                try:
+                    # generate a ROS node prefix from the basename of argv[0]
+                    clean_name = ''.join([c for c in sys.argv[0].rsplit('/',1)[-1].replace('.', '_').replace('-','_') if c.lower() in 'abcdefghijklmnoprqstuvwxzy0123456789_'])
+                except:
+                    clean_name = ''
+                rospy.init_node('ipaaca_python' if len(clean_name)==0 else clean_name,
+                        anonymous=True, disable_signals=True)
+
+        def _get_name(self):
+            return self._name
+        name = property(_get_name)
+
+        def teardown(self):
+            LOGGER.info('ROS teardown: waiting 1 sec for final deliveries')
+            time.sleep(1)
+            rospy.signal_shutdown('Done')
+
+        @staticmethod
+        def serialize(obj):
+            #print('object class: '+obj.__class__.__name__)
+            bb = ipaaca.converter.serialize(obj)
+            st = str(base64.b64encode(bb))
+            #print('serialized: '+str(st))
+            return st
+        
+        @staticmethod
+        def deserialize(msg):
+            #print('got serialized: '+str(msg))
+            bb = base64.b64decode(msg)
+            return ipaaca.converter.deserialize(bb)
+        
+        def Scope(self, scope_str):
+            '''Scope adapter (glue replacing rsb.Scope)'''
+            # ROS graph resources must not start with a slash
+            return str(scope_str)[1:] if scope_str.startswith('/') else str(scope_str)
+
+        def createLocalServer(self, buffer_impl, scope, config=None):
+            self.init_once()
+            LOGGER.debug('Creating a LocalServer on '+str(scope))
+            LOGGER.debug('              from thread '+threading.current_thread().name)
+            s = LocalServer(buffer_impl, scope, self._config if config is None else config)
+            #s._live_event.wait(30.0)
+            return s
+         
+        def createRemoteServer(self, scope, config=None):
+            self.init_once()
+            LOGGER.debug('Creating a RemoteServer on '+str(scope))
+            LOGGER.debug('               from thread '+threading.current_thread().name)
+            s = RemoteServer(scope, self._config if config is None else config)
+            #s._live_event.wait(30.0)
+            return s
+
+        def createInformer(self, scope, config=None, dataType="ignored in this backend"):
+            self.init_once()
+            LOGGER.debug('Creating an Informer on '+str(scope))
+            LOGGER.debug('            from thread '+threading.current_thread().name)
+            s = Informer(scope, self._config if config is None else config)
+            #s._live_event.wait(30.0)
+            return s
+
+        def createListener(self, scope, config=None):
+            self.init_once()
+            LOGGER.debug('Creating a Listener on '+str(scope))
+            LOGGER.debug('           from thread '+threading.current_thread().name)
+            s = Listener(scope, self._config if config is None else config)
+            #s._live_event.wait(30.0)
+            return s
+            
+
+

ipaacalib/python/src/ipaaca/buffer.py

@@ -4,7 +4,7 @@
 #  "Incremental Processing Architecture
 #   for Artificial Conversational Agents".
 #
-# Copyright (c) 2009-2015 Social Cognitive Systems Group
+# Copyright (c) 2009-2022 Social Cognitive Systems Group
 #                         CITEC, Bielefeld University
 #
 # http://opensource.cit-ec.de/projects/ipaaca/
@@ -37,17 +37,18 @@ import threading
 import uuid
 import traceback
 
+import six
 import weakref
 import atexit
 
-import rsb
+#import rsb
 
 import ipaaca.ipaaca_pb2
 import ipaaca.defaults
 import ipaaca.exception
 import ipaaca.converter
 import ipaaca.iu
-
+import ipaaca.backend
 
 __all__ = [
 	'InputBuffer',
@@ -65,6 +66,7 @@ def atexit_cleanup_function():
 		obj = obj_r()
 		if obj is not None: # if weakref still valid
 			obj._teardown()
+	ipaaca.backend.get_default_backend().teardown()
 atexit.register(atexit_cleanup_function)
 
 def auto_teardown_instances(fn):
@@ -112,10 +114,10 @@ class IUEventHandler(object):
 		self._handler_function = handler_function
 		self._for_event_types = (
 			None if for_event_types is None else
-			(for_event_types[:] if hasattr(for_event_types, '__iter__') else [for_event_types]))
+			(for_event_types[:] if not isinstance(for_event_types, six.string_types) and hasattr(for_event_types, '__iter__') else [for_event_types]))
 		self._for_categories = (
 			None if for_categories is None else
-			(for_categories[:] if hasattr(for_categories, '__iter__') else [for_categories]))
+			(for_categories[:] if not isinstance(for_categories, six.string_types) and hasattr(for_categories, '__iter__') else [for_categories]))
 
 	def condition_met(self, event_type, category):
 		"""Check whether this IUEventHandler should be called.
@@ -158,7 +160,7 @@ class Buffer(object):
 		ipaaca.initialize_ipaaca_rsb_if_needed()
 		self._owning_component_name = owning_component_name
 		self._channel = channel if channel is not None else ipaaca.defaults.IPAACA_DEFAULT_CHANNEL
-		self._participant_config = rsb.ParticipantConfig.fromDefaultSources() if participant_config is None else participant_config
+		self._participant_config = participant_config
 		self._uuid = str(uuid.uuid4())[0:8]
 		# Initialise with a temporary, but already unique, name
 		self._unique_name = "undef-"+self._uuid
@@ -169,6 +171,12 @@ class Buffer(object):
 		return FrozenIUStore(original_iu_store = self._iu_store)
 	iu_store = property(fget=_get_frozen_iu_store, doc='Copy-on-read version of the internal IU store')
 
+	def _get_channel(self):
+		return self._channel
+	channel = property(
+			fget=_get_channel,
+			doc='The IPAACA channel the buffer is connected to.')
+
 	def register_handler(self, handler_function, for_event_types=None, for_categories=None):
 		"""Register a new IU event handler function.
 
@@ -192,9 +200,9 @@ class Buffer(object):
 				h.call(self, uid, local=local, event_type=event_type, category=category)
 			except Exception as e:
 				if local:
-					LOGGER.error('Local IU handler raised an exception upon remote write.' + unicode(e))
+					LOGGER.error('Local IU handler raised an exception upon remote write.' + str(e))
 				else:
-					print(unicode(traceback.format_exc()))
+					print(str(traceback.format_exc()))
 					raise e
 	
 	def _get_owning_component_name(self):
@@ -234,13 +242,14 @@ class InputBuffer(Buffer):
 	
 	def _get_remote_server(self, event_or_iu):
 		'''Return (or create, store and return) a remote server.'''
-		_owner = self._get_owner(event_or_iu)
-		if _owner:
+		_remote_server_name = self._get_owner(event_or_iu) + '/Server'
+		if _remote_server_name:
 			try:
-				return self._remote_server_store[_owner]
+				return self._remote_server_store[_remote_server_name]
 			except KeyError:
-				remote_server = rsb.createRemoteServer(rsb.Scope(str(_owner)))
-				self._remote_server_store[_owner] = remote_server
+				be = ipaaca.backend.get_default_backend()
+				remote_server = be.createRemoteServer(be.Scope(str(_remote_server_name)), config=self._participant_config)
+				self._remote_server_store[_remote_server_name] = remote_server
 				return remote_server
 		else:
 			None
@@ -262,7 +271,8 @@ class InputBuffer(Buffer):
 	def _add_category_listener(self, iu_category):
 		'''Create and store a listener on a specific category.'''
 		if iu_category not in self._listener_store:
-			cat_listener = rsb.createListener(rsb.Scope("/ipaaca/channel/"+str(self._channel)+"/category/"+str(iu_category)), config=self._participant_config)
+			be = ipaaca.backend.get_default_backend()
+			cat_listener = be.createListener(be.Scope("/ipaaca/channel/"+str(self._channel)+"/category/"+str(iu_category)), config=self._participant_config)
 			cat_listener.addHandler(self._handle_iu_events)
 			self._listener_store[iu_category] = cat_listener
 			self._category_interests.append(iu_category)
@@ -303,7 +313,7 @@ class InputBuffer(Buffer):
 		event -- a converted RSB event
 		'''
 		type_ = type(event.data)
-		if type_ is ipaaca.iu.RemotePushIU:
+		if type_ == ipaaca.iu.RemotePushIU:
 			# a new IU
 			if event.data.uid not in self._iu_store:
 				self._iu_store[event.data.uid] = event.data
@@ -316,7 +326,7 @@ class InputBuffer(Buffer):
 				# done via the resend request mechanism).
 				self._iu_store[event.data.uid] = event.data
 				event.data.buffer = self
-		elif type_ is ipaaca.iu.RemoteMessage:
+		elif type_ == ipaaca.iu.RemoteMessage:
 			# a new Message, an ephemeral IU that is removed after calling handlers
 			self._iu_store[ event.data.uid ] = event.data
 			event.data.buffer = self
@@ -325,7 +335,7 @@ class InputBuffer(Buffer):
 		else:
 			if event.data.uid not in self._iu_store:
 				if (self._resend_active and 
-							not type_ is ipaaca.ipaaca_pb2.IURetraction):
+							not type_ == ipaaca.ipaaca_pb2.IURetraction):
 					# send resend request to remote server, IURetraction is ignored
 					try:
 						self._request_remote_resend(event)
@@ -336,7 +346,7 @@ class InputBuffer(Buffer):
 					LOGGER.warning("Received an update for an IU which we did not receive before.")
 				return
 			# an update to an existing IU
-			if type_ is ipaaca.ipaaca_pb2.IURetraction:
+			if type_ == ipaaca.ipaaca_pb2.IURetraction:
 				# IU retraction (cannot be triggered remotely)
 				iu = self._iu_store[event.data.uid]
 				iu._revision = event.data.revision
@@ -347,18 +357,18 @@ class InputBuffer(Buffer):
 					# Notify only for remotely triggered events;
 					# Discard updates that originate from this buffer
 					return
-				if type_ is ipaaca.ipaaca_pb2.IUCommission:
+				if type_ == ipaaca.ipaaca_pb2.IUCommission:
 					# IU commit
 					iu = self._iu_store[event.data.uid]
 					iu._apply_commission()
 					iu._revision = event.data.revision
 					self.call_iu_event_handlers(event.data.uid, local=False, event_type=ipaaca.iu.IUEventType.COMMITTED, category=iu.category)
-				elif type_ is ipaaca.converter.IUPayloadUpdate:
+				elif type_ == ipaaca.converter.IUPayloadUpdate:
 					# IU payload update
 					iu = self._iu_store[event.data.uid]
 					iu._apply_update(event.data)
 					self.call_iu_event_handlers(event.data.uid, local=False, event_type=ipaaca.iu.IUEventType.UPDATED, category=iu.category)
-				elif type_ is ipaaca.converter.IULinkUpdate:
+				elif type_ == ipaaca.converter.IULinkUpdate:
 					# IU link update
 					iu = self._iu_store[event.data.uid]
 					iu._apply_link_update(event.data)
@@ -367,14 +377,14 @@ class InputBuffer(Buffer):
 					LOGGER.warning('Warning: _handle_iu_events failed to handle an object of type '+str(type_))
 
 	def add_category_interests(self, category_interests):
-		if hasattr(category_interests, '__iter__'):
+		if not isinstance(category_interests, six.string_types) and hasattr(category_interests, '__iter__'):
 			for interest in category_interests:
 				self._add_category_listener(interest)
 		else:
 			self._add_category_listener(category_interests)
 
 	def remove_category_interests(self, category_interests):
-		if hasattr(category_interests, '__iter__'):
+		if not isinstance(category_interests, six.string_types) and hasattr(category_interests, '__iter__'):
 			for interest in category_interests:
 				self._remove_category_listener(interest)
 		else:
@@ -386,12 +396,12 @@ class InputBuffer(Buffer):
 			resend_request = ipaaca.ipaaca_pb2.IUResendRequest()
 			resend_request.uid = event.data.uid # target iu
 			resend_request.hidden_scope_name = str(self._uuid) # hidden category name
-			remote_revision = remote_server.requestResend(resend_request)
+			remote_revision = remote_server.resendRequest(resend_request)
 			if remote_revision == 0:
-				raise ipaaca.exception.IUResendRequestFailedError()
+				raise ipaaca.exception.IUResendRequestFailedError(event.data.uid)
 		else:
 			# Remote server is not known
-			raise ipaaca.exception.IUResendRequestFailedError()
+			raise ipaaca.exception.IUResendRequestRemoteServerUnknownError(event.data.uid)
 
 	def register_handler(self, handler_function, for_event_types=None, for_categories=None):
 		"""Register a new IU event handler function.
@@ -433,11 +443,8 @@ class OutputBuffer(Buffer):
 		'''
 		super(OutputBuffer, self).__init__(owning_component_name, channel, participant_config)
 		self._unique_name = '/ipaaca/component/' + str(owning_component_name) + 'ID' + self._uuid + '/OB'
-		self._server = rsb.createLocalServer(rsb.Scope(self._unique_name))
-		self._server.addMethod('updateLinks', self._remote_update_links, ipaaca.converter.IULinkUpdate, int)
-		self._server.addMethod('updatePayload', self._remote_update_payload, ipaaca.converter.IUPayloadUpdate, int)
-		self._server.addMethod('commit', self._remote_commit, ipaaca.ipaaca_pb2.IUCommission, int)
-		self._server.addMethod('requestResend', self._remote_request_resend, ipaaca.ipaaca_pb2.IUResendRequest, int)
+		be = ipaaca.backend.get_default_backend()
+		self._server = be.createLocalServer(self, be.Scope(self._unique_name + '/Server'), config=self._participant_config)
 		self._informer_store = {}
 		self._id_prefix = str(owning_component_name)+'-'+str(self._uuid)+'-IU-'
 		self.__iu_id_counter_lock = threading.Lock()
@@ -482,10 +489,10 @@ class OutputBuffer(Buffer):
 		with iu.revision_lock:
 			if (update.revision != 0) and (update.revision != iu.revision):
 				# (0 means "do not pay attention to the revision number" -> "force update")
-				LOGGER.warning(u"Remote update_payload operation failed because request was out of date; IU "+str(update.uid))
-				LOGGER.warning(u"  Writer was: "+update.writer_name)
-				LOGGER.warning(u"  Requested update was: (New keys:) "+','.join(update.new_items.keys())+'  (Removed keys:) '+','.join(update.keys_to_remove))
-				LOGGER.warning(u"  Referred-to revision was "+str(update.revision)+' while local revision is '+str(iu.revision))
+				LOGGER.warning("Remote update_payload operation failed because request was out of date; IU "+str(update.uid))
+				LOGGER.warning("  Writer was: "+update.writer_name)
+				LOGGER.warning("  Requested update was: (New keys:) "+','.join(update.new_items.keys())+'  (Removed keys:) '+','.join(update.keys_to_remove))
+				LOGGER.warning("  Referred-to revision was "+str(update.revision)+' while local revision is '+str(iu.revision))
 				return 0
 			if update.is_delta:
 				#print('Writing delta update by '+str(update.writer_name))
@@ -508,7 +515,7 @@ class OutputBuffer(Buffer):
 			return 0
 		iu = self._iu_store[iu_resend_request_pack.uid]
 		with iu.revision_lock:
-			if iu_resend_request_pack.hidden_scope_name is not None and iu_resend_request_pack.hidden_scope_name is not '':
+			if iu_resend_request_pack.hidden_scope_name is not None and iu_resend_request_pack.hidden_scope_name != '':
 				informer = self._get_informer(iu_resend_request_pack.hidden_scope_name)
 				informer.publishData(iu)
 				return iu.revision
@@ -538,8 +545,9 @@ class OutputBuffer(Buffer):
 		if iu_category in self._informer_store:
 			LOGGER.info("Returning informer on scope "+"/ipaaca/channel/"+str(self._channel)+"/category/"+str(iu_category))
 			return self._informer_store[iu_category]
-		informer_iu = rsb.createInformer(
-				rsb.Scope("/ipaaca/channel/"+str(self._channel)+"/category/"+str(iu_category)),
+		be = ipaaca.backend.get_default_backend()
+		informer_iu = be.createInformer(
+				be.Scope("/ipaaca/channel/"+str(self._channel)+"/category/"+str(iu_category)),
 				config=self._participant_config,
 				dataType=object)
 		self._informer_store[iu_category] = informer_iu #new_tuple

ipaacalib/python/src/ipaaca/config.py

+# -*- coding: utf-8 -*-
+
+# This file is part of IPAACA, the
+#  "Incremental Processing Architecture
+#   for Artificial Conversational Agents".
+#
+# Copyright (c) 2009-2022 Social Cognitive Systems Group
+#                         CITEC, Bielefeld University
+#
+# http://opensource.cit-ec.de/projects/ipaaca/
+# http://purl.org/net/ipaaca
+#
+# This file may be licensed under the terms of of the
+# GNU Lesser General Public License Version 3 (the ``LGPL''),
+# or (at your option) any later version.
+#
+# Software distributed under the License is distributed
+# on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+# express or implied. See the LGPL for the specific language
+# governing rights and limitations.
+#
+# You should have received a copy of the LGPL along with this
+# program. If not, go to http://www.gnu.org/licenses/lgpl.html
+# or write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# The development of this software was supported by the
+# Excellence Cluster EXC 277 Cognitive Interaction Technology.
+# The Excellence Cluster EXC 277 is a grant of the Deutsche
+# Forschungsgemeinschaft (DFG) in the context of the German
+# Excellence Initiative.
+
+from __future__ import division, print_function
+
+import ipaaca.defaults
+import ipaaca.exception
+import ipaaca.iu
+import ipaaca.misc
+
+import os
+import re
+try:
+    import configparser
+except:
+    import ConfigParser as configparser
+
+
+LOGGER = ipaaca.misc.get_library_logger()
+
+__global_config = None
+
+class Config(object):
+    def __init__(self):
+        self._store = {}
+
+    def get_with_default(self, key, default_value, warn=False):
+        if key in self._store:
+            return self._store[key]
+        else:
+            notif = LOGGER.warning if warn else LOGGER.debug
+            notif('Config key '+str(key)+' not found, returning default of '+str(default_value))
+            return default_value
+    
+    def populate_from_global_sources(self):
+        self._store = {}
+        self.populate_from_any_conf_files()
+        self.populate_from_environment()
+        #self.populate_from_argv_overrides() # TODO IMPLEMENT_ME
+
+    def populate_from_any_conf_files(self):
+        globalconf = os.getenv('HOME', '')+'/.config/ipaaca.conf'
+        for filename in ['ipaaca.conf', globalconf]:
+            try:
+                f = open(filename, 'r')
+                c = configparser.ConfigParser()
+                c.readfp(f)
+                f.close()
+                LOGGER.info('Including configuration from '+filename)
+                for k,v in c.items('ipaaca'):
+                    self._store[k] = v
+                return
+            except:
+                pass
+        LOGGER.info('Could not load ipaaca.conf either here or in ~/.config')
+
+    def populate_from_environment(self):
+        for k, v in os.environ.items():
+            if k.startswith('IPAACA_'):
+                if re.match(r'^[A-Za-z0-9_]*$', k) is None:
+                    LOGGER.warning('Ignoring malformed environment key')
+                else:
+                    if len(v)>1023:
+                        LOGGER.warning('Ignoring long environment value')
+                    else:
+                        # remove initial IPAACA_ and transform key to dotted lowercase
+                        trans_key = k[7:].lower().replace('_', '.')
+                        self._store[trans_key] = v
+                        LOGGER.debug('Configured from environment: '+str(trans_key)+'="'+str(v)+'"')
+
+
+def get_global_config():
+    global __global_config
+    if __global_config is None:
+        __global_config = Config()
+        __global_config.populate_from_global_sources()
+    return __global_config
+