How do I get the output of a specific step in GitHub Actions? - github

Question

I have this GitHub Actions workflow which runs tests, but now I am integrating slack notification in it. I want to get the output of the Run tests step and send it as a message in the slack step.
- name: Run tests
run: |
mix compile --warnings-as-errors
mix format --check-formatted
mix ecto.create
mix ecto.migrate
mix test
env:
MIX_ENV: test
PGHOST: localhost
PGUSER: postgres
- name: Slack Notification
uses: rtCamp/action-slack-notify#master
env:
SLACK_MESSAGE: Run tests output
SLACK_TITLE: CI Test Suite
SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}

Answer 1

You need to do 3 things:
Add an id to the step you want the output from
Create the outputs using the GITHUB_OUTPUT environment variable
Use the id and the output name in another step to get the outputs and then join them into one message for slack
- name: Run tests
run: |
echo "mix-compile--warnings-as-errors=$(mix compile --warnings-as-errors)\n" >> $GITHUB_OUTPUT
echo "mix-format--check-formatted=$(mix format --check-formatted)\n" >> $GITHUB_OUTPUT
echo "mix-ecto_create=$(mix ecto.create)\n" >> $GITHUB_OUTPUT
echo "mix-ecto_migrate=$(mix ecto.migrate)\n" >> $GITHUB_OUTPUT
echo "mix-test=$(mix test)\n" >> $GITHUB_OUTPUT
id: run_tests
env:
MIX_ENV: test
PGHOST: localhost
PGUSER: postgres
- name: Slack Notification
uses: rtCamp/action-slack-notify#v2
env:
SLACK_MESSAGE: ${{join(steps.run_tests.outputs.*, '\n')}}
SLACK_TITLE: CI Test Suite
SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}
See Metadata Syntax for outputs name description

Answer 2

The problem with the current accepted answer is that the result for the step will always be success since the test execution result is being masked by the echo command.
This modification to the last line should work in preserving the original exit status:
mix test 2>&1 | tee test.log
result_code=${PIPESTATUS[0]}
echo "::set-output name=mix-test::$(cat test.log)"
exit $result_code

Answer 3

I made an action with the same interface as run that stores stdout and stderr in output variables to maybe simplify some cases like this:
- name: Run tests
uses: mathiasvr/command-output#v1
id: tests
with:
run: |
mix compile --warnings-as-errors
mix format --check-formatted
mix ecto.create
mix ecto.migrate
mix test
- name: Slack Notification
uses: rtCamp/action-slack-notify#master
env:
SLACK_MESSAGE: ${{ steps.tests.outputs.stdout }}
SLACK_TITLE: CI Test Suite
SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}

Answer 4

I just wanted to add #smac89's solution was helpful but didn't quite work for me. I'm using a different Slack action (pullreminders/slack-action) to build more specific content. I found that I was getting single-quotes where each newline was, and my leading spaces on each line were also being truncated. After reading https://github.com/actions/toolkit/issues/403 and playing around, I found that in my case, I needed newlines to actually be escaped in the output (a literal \n), so I replaced \n characters with \\n. Then, I replaced regular space characters with a Unicode 'En Space' character.
Here's what worked:
Bash Run Step:
Tools/get-changed-fields.sh src/objects origin/${{ env.DIFF_BRANCH }} > changed-fields.out
output="$(cat changed-fields.out)"
output="${output//$'\n'/\\n}"
output="${output// / }" # replace regular space with 'En Space'
echo "::set-output name=changed-fields-output::$output"
Slack Notification Step:
- name: Changed Fields Slack Notification
if: ${{ success() && steps.summarize-changed-fields.outputs.changed-fields-output != '' && steps.changed-fields-cache.outputs.cache-hit != 'true' }}
env:
SLACK_BOT_TOKEN: ${{ secrets.SLACK_BOT_TOKEN }}
uses: pullreminders/slack-action#master
with:
args: '{\"channel\":\"${{ env.SUCCESS_SLACK_CHANNEL }}\",\"attachments\":[{\"color\":\"#36a64f\",\"title\":\"Changed Fields Report:\",\"author_name\":\"${{ github.workflow }} #${{ github.run_number }}: ${{ env.BRANCH }} -> ${{ env.TARGET_ORG }} (by: ${{ github.actor }})\",\"author_link\":\"${{ github.server_url }}/${{ github.repository }}/runs/${{ github.run_id }}\",\"text\":\"```\n${{ steps.summarize-changed-fields.outputs.changed-fields-output }}\n```\"}]}'