Drone environment variables are no longer being expanded when passed to plugin settings

Drone Support
1

I’m using drone at cloud.drone.io (not sure what ersion that is) and since today, environment variables are not getting expanded/evaluated any longer when used in the settings of a plugin or as part of the image name.
Here is my step config:

  - name: build
    image: plugins/docker
    settings:
      tags: "tst-${DRONE_COMMIT_SHA}"
      dockerfile: ./Dockerfile
      repo: oliver006/drone-gcf
...

This used to tag and publish the image as expected but not any longer.

Similarly, using

  - name: deploy-test-cloud-function-test
    image: "oliver006/drone-gcf:tst-${DRONE_COMMIT_SHA}"

now fails with a cryptic invalid reference format error as it seems to not evaluate/expand the env variable any longer.

Did any change? Do I need to do something different when using the env variables?

2

sorry, I am unable to reproduce. I created a branch to test [1] and everything was working as expected [2]. You can find the yaml substitution source code on github [3][4] it you are interested in auditing the code further.

for quick reference, here is the yaml I used:

kind: pipeline
name: default

steps:
- name: build
  image: plugins/docker
  settings:
    repo: hello-world-${DRONE_COMMIT_SHA}
    tags: latest
    dry_run: true

and in the build logs I see this (commit sha in repository name) which demonstrates that the substitution worked:

+ /usr/local/bin/docker tag bc774c56e008f6134c4debaa80fcc932adcd00f4
hello-world-56e008f6134c4debaa80fcc932adcd00f4:latest

[1] https://github.com/drone/hello-world/commits/test-yaml-subst
[2] https://cloud.drone.io/drone/hello-world/36/1/2
[3] https://github.com/drone/drone/blame/master/operator/runner/runner.go#L186:L192
[4] https://github.com/drone/envsubst

3

My bad, I must have messed up something pretty badly with my .drone.yml file. I created the file from scratch and it now works, not really sure what it was but it’s all good now, thanks for your quick help!

4

ok great, glad to hear that you got it working :slight_smile:

5

I figured out what triggered the issue. Somewhere, way down in the drone.yml file, i accidentally used ${$DRONE_TAG} (note the extra $ inside the { ... }).

This would completely mess up any sort of DRONE_ env variable substitution in all other steps in the drone file.

No idea why but I figured I’d update this thread in case someone else stumbles upon this.