I found a way for connect app in docker container to local database which located on my osx.

0.0.0.0:5432 is an localhost address of container (not a localhost of osx) and we must set new one:

1. Find osx Ip local address in Preferences > Network Settings (my was 192.168.0.102)
2. Add this Ip to line listener_address: '192.168.0.102, localhost' of postgresql config file.
3. Add extra line with Ip 192.168.0.102, host and md5 to pg_hba.conf file
4. Restart Postgresql

Set connection settings in app via ENV like: postgres://postgres:testing@192.168.0.102:5432/movies_development

There may be two reasons as per your question :

• Have you exposed EXPOSE 5432 during your docker image build ? or before starting container with docker run -it -d --name $container_name -p 5432:5432 $image_name ? If NO than you must have to do any of above changes than and than it can connect to externally hosted database.
• If your are going inside your docker container with docker exec -it $container_name bash and executing command this psql "postgres://postgres:testing@0.0.0.0:5432/movies_development" then there must be psql client installed in your docker container with proper $PATH variable otherwise it will throw error like command not found/no such file or directory.
• Note: if your application is using some other way to communicate with database than your application will work without psql client program.

Hope this help.Thank you!