Where are Go templates allowed in docker-compose files?

Question

The title is self explanatory: I wasn't able to find a document describing where Go templates are allowed in compose files.

In other words I wish to know which of the following is supported:

version: "3.7"


services:
  whoami:
    image: "containous/whoami"
    environment:
      - VALUE='{{.Name}}'
      - NAME_{{.Name}}='NAME'
    deploy:
      labels:
        - value={{.Name}}
        - name_{{.Name}}=NAME
    networks:
      - {{.Name}}

Answer 1

I kept searching and apparently the information is actually provided in the official Docker documentation, even if it doesn't explicitly refer to the docker compose file format.

In particular:

You can use templates for some flags of service create, using the syntax provided by the Go’s text/template package.

The supported flags are the following :

--hostname --mount --env

As --labels is not listed we should assume text/template replacement is not allowed in there.