Using latest ipython with docker to correctly access a postgresql db from another container.
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## SHELL 1
docker-compose up
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## SHELL 2
# wait for pip install to complete
docker-compose exec app ipython
# ... do you python code here ...
# (e.g. see test.ipy)
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## SHELL 3
## debug db:
# docker-compose exec db psql -U postgres
# verify size increasing
docker-compose exec db ash
du -sh /var/lib/postgresql/data/base
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## END
docker-compose down -v