No image or build context specified error when using override file

[joltcoke]

The tool causing the error is esc-cli, but apparently it's due to a limitation in libcompose. I've initially filed an issue with ecs-cli (aws/amazon-ecs-cli#393 (comment)) but they asked me to file one here. So here we go:

I have a docker-compose.yml (which doesn't contain a build or image setting) and a docker-compose.override.yml (which contains an image setting).

Trying to run "ecs-cli compose create" will result in the following error:

Service 'xyz' has neither an image nor a build context specified
Seems like ecs-cli is evaluating the existence of either build or image settings per file instead of merging all files before doing the check. docker-compose works just fine with the same configuration files.

Workaround: Adding a fake "build: ." setting to docker-compose.yml