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Docker Compose here. I'm looking at the Docker networking guide and trying to understand how to perform the equivalent of a "CREATE TABLE IF NOT EXISTS" with a Docker network. Meaning, in SQL, you can usually tell the RDBMS to create a table if it doesn't already exist.

Here, from inside a Docker Compose file, I want to tell Docker to create a network if it doesn't already exist, and then connect my services (containers) to it.

Is this possible to do? Ideally it could be flexible such that I could have several different Docker Compose files (docker-compose-a.yml, docker-compose-b.yml and docker-compose-c.yml), and all of them defined various services (containers), but all of them were configured to create (unless already created previously) and use the same "fizzbuzz" network.

Any ideas?

Answers

There's no way at the moment to create network if does not exist.

You can read more here.

Update 1

As you said in comments, you can add this to your docker-compose files (each one) in order to be in the same network.

First of all create a network by this command:

docker network create NAME

Then add this to docker-compose files:

// from here to next comment is your docker-compose current status
version: '3'

services:
  web:
    image: some
// end here your current
// here is the part you should add for network
networks:
  default:
    external:
      name: NAME

Note that before running docker-compose up -d, you should create the network or you'll get network does not exist error.