CircleCI Workflow Notifications on Slack

This is a sample project to show how to send notifications at the end of CircleCI workflows to Slack.

Prerequisites

Please make sure you have the following:

A CircleCI account
An aws account with access to AWS Lambda
A Slack Bot User OAuth token with chat:write scope

Installation

First clone this repository to your local machine and change into the project directory

git clone git@github.com:ogii/circleci-workflows-slack.git
cd circleci-workflows-slack

Next install the dependencies locally:

npm install

Following that, you will need to compress the files:

zip -r awslambda.zip .

The next step will be to upload the zip file to AWS Lambda. After creating a function in AWS Lambda, please upload the zip file via the upload from dropdown button.

Next, you will need to set the follow environment values under the Configuration tab:

Environment Variable
SLACK_ACCESS_TOKEN
SLACK_API_URL
SLACK_DEFAULT_CHANNEL

where SLACK_API_URL is equal to https://slack.com/api/chat.postMessage.

Lastly, copy the Function URL from the function dashboard, and set the following for a webhook under the project settings page for your project on CircleCI:

Webhook name
Receiver URL (function URL from above)
Secret token (if applicable)
✅ Certificate verification
✅ Workflow Completed

Message Templates

The template is currently in index.js, and is defined as follows:

  [
		{
			"type": "header",
			"text": {
				"type": "plain_text",
				"text": "${setStatus(status)}",
				"emoji": true
			}
		},
		{
			"type": "section",
			"fields": [
				{
					"type": "mrkdwn",
					"text": "*Workflow:* ${name}"
				}
			]
		},
		{
			"type": "section",
			"fields": [
				{
					"type": "mrkdwn",
					"text": "*Project:* ${slug}"
				},
				{
					"type": "mrkdwn",
					"text": "*Branch:* ${branch}"
				},
				{
					"type": "mrkdwn",
					"text": "*Created:* ${created_at}"
				},
				{
					"type": "mrkdwn",
					"text": "*Finished:* ${stopped_at}"
				},
				{
					"type": "mrkdwn",
					"text": "*Commit:* <${target_repository_url}/commit/${revision}|${revision}>"
				}
			]
		},
		{
			"type": "context",
			"elements": [
				{
					"type": "mrkdwn",
					"text": "*<${url}|View the workflow on CircleCI>*"
				}
			]
		}
	]

Example Screenshot

Considerations & Improvements

Currently the script does not do signature verification.

Documentation & References

For more information on CircleCI Webhooks, please check the following page:

https://circleci.com/docs/webhooks