Build target doesn't work in compose 1.19

[lig]

I have the following in docker-compose.yml:

version: '3'
services:
  app:
    build:
      context: .
      target: app

I'm using docker-compose version 1.19.0, build 9e633ef installed via pip3.

After running docker-compose build the expected result is to have the container for app service build with --target docker argument set to app.

The actual result is

ERROR: The Compose file './docker-compose.yml' is invalidbecause:
services.app.build contains unsupported option: 'target'

Related issues

I've found this issue #5322 which states in comments that the build target is supported since 1.17.

Also, I've found this issue docker/docs#6036 which states that the syntax is the same as for 2.x compose file version.

[lig]

The issue was I've used version 3 which is not the latest from 3.x series as I thought. One needs to use at least version 3.4 for build target to work.

[bossjones]

Just wanted to say thanks for this, for some reason I assumed if you put '3' as the version type, it would default to the latest supported version of '3' your docker client supports, but I was wrong. Doing the steps above, in my case, 3 -> 3.7 worked. ^^

[patricknelson]

Also pretty confusing for me, since this is documented in version 2 as well. I assumed that if it was available in 2.3 then naturally it'd also automatically be available in 3. Turns out that's not the case, for some reason.

[akopchinskiy]

The issue was I've used version 3 which is not the latest from 3.x series as I thought. One needs to use at least version 3.4 for build target to work.

Same error at 3.7.4

D:\WORK\Projects\api>docker-compose version
docker-compose version 1.25.5, build 8a1c60f6
docker-py version: 4.1.0
CPython version: 3.7.4
OpenSSL version: OpenSSL 1.1.1c  28 May 2019

D:\WORK\Projects\api>docker-compose up
ERROR: The Compose file '.\docker-compose.yml' is invalid because:
services.api.build contains unsupported option: 'target'
services.synchronizer.build contains unsupported option: 'target'

[patricknelson]

@akopchinskiy in this case the version is in reference to the version of the YAML content not necessarily the version of docker-compose that you have instead.

Specifically: Did you try editing docker-compose.yml so that the first line version: '3' reads version: '3.7' instead?

[akopchinskiy]

@patricknelson

Did you try editing docker-compose.yml so that the first line version: '3' reads version: '3.7' instead?

I did try and it's working. Thank you!