This is useful to display to the user the status of your deployment. For example, you could display the results of a
terraform apply
in the deployment comment
There are two ways to add custom deployment messages to your PRs. You can either use a custom markdown file (suggested) or use the GitHub Actions environment to dynamically pass data to the post run workflow which will be rendered as markdown into a comment on your pull request.
This option is highly recommended over the latter "GitHub Actions Environment" option. This is because GitHub Actions has some limitations on the size of data that can be passed around in environment variables. This becomes an issue if your deployment message is large (contains many changes, think Terraform plan/apply) as your deployment will crash with an
Argument list too long
error.
To use a custom markdown file as your post deployment message, simply use the deploy_message_path
input option to point to a markdown file in your repository that you wish to render into the comment on your pull request. You don't even need to set this value if you want to just use the default file path of ".github/deployment_message.md"
and place your markdown file there.
If a markdown file exists at the designated path, it will be used and rendered with nunjucks which is a Jinja like template engine for NodeJS. Since we are using nunjucks and are leveraging template rendering, a few variables are available for you to use in your markdown file (should you choose to use them):
environment
- The name of the environment (String)environment_url
- The URL of the environment (String) {Optional}status
- The status of the deployment (String) -success
,failure
, orunknown
noop
- Whether or not the deployment is a noop (Boolean)ref
- The ref of the deployment (String)sha
- The sha of the deployment (String)actor
- The GitHub username of the actor who triggered the deployment (String)approved_reviews_count
- The number of approved reviews on the pull request at the time of deployment (String of a number)review_decision
- The review status of the pull request (String or null) - Ex:APPROVED
,REVIEW_REQUIRED
,CHANGES_REQUESTED
,null
etc.deployment_id
- The ID of the deployment (Int or null in the case of.noop
deployments)fork
- Whether or not the repository is a fork (Boolean)params
- The raw string of deployment parameters (String)parsed_params
- A string representation of the parsed deployment parameters (String)deployment_end_time
- The time the deployment ended - this value is not exact but it is very close (String) ISO 8601 UTC formatlogs
- The URL to the logs of the deployment (String)commit_verified
- Whether or not the commit was verified (Boolean)total_seconds
- The total number of seconds the deployment took to complete (String of a number)
If you wish to see a live example of how this works, and how to use the variables, you can check out this example which is used in this repo's unit tests and is self-documenting.
Here is an example of what the final product could look like:
To learn more about these changes you can view the pull request that implemented them here
This option is not suggested as it comes with inherent limitations. See the "Custom Markdown File" section above for more information. It is highly recommended to use the custom markdown file option instead. However, if you are unable to use the custom markdown file option, this is an alternative
You can use the GitHub Actions environment to export custom deployment messages from your workflow to be referenced in the post run workflow for the branch-deploy
Action that comments results back to your PR
Simply set the environment variable DEPLOY_MESSAGE
to the message you want to be displayed in the post run workflow
Bash Example:
echo "DEPLOY_MESSAGE=<message>" >> $GITHUB_ENV
Actions Workflow Example:
# Do some fake "noop" deployment logic here
- name: fake noop deploy
if: ${{ steps.branch-deploy.outputs.continue == 'true' && steps.branch-deploy.outputs.noop == 'true' }}
run: |
echo "DEPLOY_MESSAGE=I would have **updated** 1 server" >> $GITHUB_ENV
echo "I am doing a fake noop deploy"
echo "DEPLOY_MESSAGE=NOOP Result:\nI would have **updated** 1 server" >> $GITHUB_ENV
Multi-line strings (reference)
echo 'DEPLOY_MESSAGE<<EOF' >> $GITHUB_ENV
echo "$SOME_MULTI_LINE_STRING_HERE" >> $GITHUB_ENV
echo 'EOF' >> $GITHUB_ENV
Where
$SOME_MULTI_LINE_STRING_HERE
is a bash variable containing a multi-line string
echo "DEPLOY_MESSAGE=\`\`\`yaml\nname: value\n\`\`\`" >> $GITHUB_ENV
To add custom messages to our final deployment message we need to use the GitHub Actions environment. This is so that we can dynamically pass data into the post action workflow that leaves a comment on our PR. The post action workflow will look to see if this environment variable is set (DEPLOY_MESSAGE
). If the variable is set, it adds to to the PR comment. Otherwise, it will use a simple comment body that doesn't include the custom message.