Add wait-for-it.sh

Dockerfile

@@ -23,6 +23,9 @@ COPY config.py opaque.py requirements.txt ./
 RUN python -m venv venv && \
     venv/bin/pip install -r requirements.txt
 
+# add wait for it
+RUN git clone https://github.com/vishnubob/wait-for-it.git /wait-for-it
+RUN chmod a+x /wait-for-it/wait-for-it.sh
 
 COPY docker-entrypoint.sh /usr/local/bin/
 ENTRYPOINT ["docker-entrypoint.sh"]

docker-entrypoint.sh

 #!/bin/sh
 
+/wait-for-it/wait-for-it.sh db:5432 --strict --timeout=0
 if [ $# -eq 0 ]
 then
     venv/bin/python -u opaque.py