How can one Docker container call another Docker container

Question

I have two Docker containers

1. A Web API
2. A Console Application that calls Web API

Now, on my local web api is local host and Console applicat

Answer 1

You can use the link option with docker run:

Run the API:

docker run -d --name api api_image

Run the client:

docker run --link api busybox ping api

You should see that api can be resolved by docker.

That said, going with docker-compose is still a better option.

Answer 2

The problem can be solved easily if using compose feature. With compose, you just create one configuration file (docker-compose.yml) like this :

version: '3'
services:
  db:
    image: postgres
  web:
    build: .
    command: python3 manage.py runserver 0.0.0.0:8000
    volumes:
      - .:/code
    ports:
      - "8000:8000"
    depends_on:
      - db

To make it run, just call up like this :

docker-compose up 

This is the best way to run all your stack, so, check this reference : https://docs.docker.com/compose/

Success!

Answer 3

The idea is not to pass the url, but the hostname of the other container you want to call.
See Networking in Compose

By default Compose sets up a single network for your app. Each container for a service joins the default network and is both reachable by other containers on that network, and discoverable by them at a hostname identical to the container name.

This is what replace the deprecated --link option.

And if your containers are not running on a single Docker server node, Docker Swarm Mode would enable that discoverability across multiple nodes.