Create or Update Comment

A GitHub action to create or update an issue or pull request comment.

This action was created to help facilitate a GitHub Actions "ChatOps" solution in conjunction with slash-command-dispatch action.

Usage

Add a comment to an issue or pull request

      - name: Create comment
        uses: peter-evans/create-or-update-comment@v2
        with:
          issue-number: 1
          body: |
            This is a multi-line test comment
            - With GitHub **Markdown** :sparkles:
            - Created by [create-or-update-comment][1]

            [1]: https://github.com/peter-evans/create-or-update-comment
          reactions: '+1'

Update a comment

      - name: Update comment
        uses: peter-evans/create-or-update-comment@v2
        with:
          comment-id: 557858210
          body: |
            **Edit:** Some additional info
          reactions: eyes

Add comment reactions

      - name: Add reactions
        uses: peter-evans/create-or-update-comment@v2
        with:
          comment-id: 557858210
          reactions: heart, hooray, laugh

Action inputs

Name	Description	Default
token	GITHUB_TOKEN (issues: write, pull-requests: write) or a repo scoped PAT.	GITHUB_TOKEN
repository	The full name of the repository in which to create or update a comment.	Current repository
issue-number	The number of the issue or pull request in which to create a comment.
comment-id	The id of the comment to update.
body	The comment body.
edit-mode	The mode when updating a comment, replace or append.	append
reactions	A comma separated list of reactions to add to the comment. (+1, -1, laugh, confused, heart, hooray, rocket, eyes)

Note: In public repositories this action does not work in pull_request workflows when triggered by forks. Any attempt will be met with the error, Resource not accessible by integration. This is due to token restrictions put in place by GitHub Actions. Private repositories can be configured to enable workflows from forks to run without restriction. See here for further explanation. Alternatively, use the pull_request_target event to comment on pull requests.

Outputs

The ID of the created comment will be output for use in later steps. Note that in order to read the step output the action step must have an id.

      - name: Create comment
        uses: peter-evans/create-or-update-comment@v2
        id: couc
        with:
          issue-number: 1
          body: |
            My comment
      - name: Check outputs
        run: |
          echo "Comment ID - ${{ steps.couc.outputs.comment-id }}"

Where to find the id of a comment

How to find the id of a comment will depend a lot on the use case. Here is one example where the id can be found in the github context during an issue_comment event.

on:
  issue_comment:
    types: [created]
jobs:
  commentCreated:
    runs-on: ubuntu-latest
    steps:
      - name: Add reaction
        uses: peter-evans/create-or-update-comment@v2
        with:
          comment-id: ${{ github.event.comment.id }}
          reactions: eyes

Some use cases might find the find-comment action useful. This will search an issue or pull request for the first comment containing a specified string, and/or by a specified author. See the repository for detailed usage.

In the following example, find-comment is used to determine if a comment has already been created on a pull request. If the find-comment action output comment-id returns an empty string, a new comment will be created. If it returns a value, the comment already exists and the content is replaced.

    - name: Find Comment
      uses: peter-evans/find-comment@v2
      id: fc
      with:
        issue-number: ${{ github.event.pull_request.number }}
        comment-author: 'github-actions[bot]'
        body-includes: Build output

    - name: Create or update comment
      uses: peter-evans/create-or-update-comment@v2
      with:
        comment-id: ${{ steps.fc.outputs.comment-id }}
        issue-number: ${{ github.event.pull_request.number }}
        body: |
          Build output
          ${{ steps.build.outputs.build-log }}
        edit-mode: replace

If required, the create and update steps can be separated for greater control.

    - name: Find Comment
      uses: peter-evans/find-comment@v2
      id: fc
      with:
        issue-number: ${{ github.event.pull_request.number }}
        comment-author: 'github-actions[bot]'
        body-includes: This comment was written by a bot!

    - name: Create comment
      if: steps.fc.outputs.comment-id == ''
      uses: peter-evans/create-or-update-comment@v2
      with:
        issue-number: ${{ github.event.pull_request.number }}
        body: |
          This comment was written by a bot!
        reactions: rocket

    - name: Update comment
      if: steps.fc.outputs.comment-id != ''
      uses: peter-evans/create-or-update-comment@v2
      with:
        comment-id: ${{ steps.fc.outputs.comment-id }}
        body: |
          This comment has been updated!
        reactions: hooray

Setting the comment body from a file

This example shows how file content can be read into a variable and passed to the action. The content must be escaped to preserve newlines.

      - id: get-comment-body
        run: |
          body="$(cat comment-body.txt)"
          body="${body//'%'/'%25'}"
          body="${body//$'\n'/'%0A'}"
          body="${body//$'\r'/'%0D'}" 
          echo "::set-output name=body::$body"

      - name: Create comment
        uses: peter-evans/create-or-update-comment@v2
        with:
          issue-number: 1
          body: ${{ steps.get-comment-body.outputs.body }}

Using a markdown template

In this example, a markdown template file is added to the repository at .github/comment-template.md with the following content.

This is a test comment template
Render template variables such as {{ .foo }} and {{ .bar }}.

The template is rendered using the render-template action and the result is used to create the comment.

      - name: Render template
        id: template
        uses: chuhlomin/[email protected]
        with:
          template: .github/comment-template.md
          vars: |
            foo: this
            bar: that

      - name: Create comment
        uses: peter-evans/create-or-update-comment@v2
        with:
          issue-number: 1
          body: ${{ steps.template.outputs.result }}

Accessing issues and comments in other repositories

You can create and update comments in another repository by using a PAT instead of GITHUB_TOKEN. The user associated with the PAT must have write access to the repository.

License

MIT