This is how you setup the action triggers for GitHub issue comments in .github/workflows/main.yml:
on:
issue_comment:
types: [created, edited]
I assume that I can also read the issue comment inside main.yml and pass it as an input argument to my action.
How do I actually read the issue comment body?
For both event types:
- run: echo ${{ github.event.comment.body }}
For edited only; get comment body before edit:
- run: echo ${{ github.event.changes.body.from }}
You can also add one extra job to your workflow while you work on it...
jobs:
dump:
runs-on: ubuntu-latest
steps:
- name: $github
run: echo "$GITHUB_CONTEXT"
env:
GITHUB_CONTEXT: ${{ toJson(github) }}
# ...
...so you can easily see all kind of data related to triggered event.
You should not run echo ${{ github.event.comment.body }}, because it potentially causes shell injection, which allows attackers do arbitrary code execution.
Run instead:
- name: print body
env:
BODY: ${{ github.event.comment.body }}
run: echo "$BODY"
Worth reading: https://securitylab.github.com/research/github-actions-untrusted-input/#remediation