docker micro-service cannot connect to bitcoin docker
the containers hosts file will differ from your hosts hosts file.

see it kind of like a VM.

Also 127.0.0.1 is the wrong address, you might need to configure the actual ip/hostname your host has and where the service is listening on inside the watchblockchain container.

So Problems:


Your docker container knows nothing about the host bitcoin. an entry in your docker hosts /etc/hosts won't change that.
Maybe your bitcoin service only binds to localhost 127.0.0.1 - this will also keep any docker container from connecting to it. Maybe you can configure it so that it binds to the docker bridge IP. So only all the docker containers are able to connect to it.
It would be easier if your bitcoind would also be a docker container and was configured inside the docker-compose.yml. That way you could resolve the host using the container name. But still your bitcoind should be configured to bind on every interface.


Hope this helps ;)