Slack

Setup Slack service

Create Slack application

In order to send notifications to your Slack channels, first you need to setup a Slack application in your workspace. An application defines the permissions and appearance of the bot that will interact with your channels. The end goal of this step is to obtain a Slack authentication token that will be used by Hermes to send notifications.

Choose one of the following two ways of creating the Slack application.

Use the manifest button

The button below will lead you to the app creation wizard in your Slack workspace where you will get to review the permissions it is requesting before adding it.

Install Manifest

Manually create the application

If you do not really trust the button above, you can instead perform this process manually.

1. Go to Slack Applications
2. Press the "Create New App" button
3. Choose the "From an app manifest" option
4. Select the workspace you wish to create the app in
5. Paste in the manifest below

manifest.yaml

_metadata:
  major_version: 1
  minor_version: 1
display_information:
  name: Hermes
features:
  bot_user:
    display_name: Hermes
    always_online: true
oauth_config:
  scopes:
    bot:
      - chat:write
      - chat:write.customize
settings:
  org_deploy_enabled: false
  socket_mode_enabled: false
  token_rotation_enabled: false

Obtain the OAuth Token

1. Go to Slack Applications
2. Select the newly created Hermes app
3. Click on "OAuth & Permissions" in the menu on the left
4. Copy the "Bot User OAuth Token" and save it for later

Example

The provided example will generate following notification in your Slack channel.

Slack token

Create a secret containing the Slack token that you obtained using the setup guide.

Access to secrets

This example assumes that your workflow will be run using a service account that has access to this secret.

apiVersion: v1
kind: Secret
metadata:
  name: slack-token
stringData:
  token: # Your Slack token goes here

Template

Add the following template:

apiVersion: v1
kind: ConfigMap
metadata:
  name: hermes-template-slack-default
data:
  primary: |
    {
      "text": "{{message}}",
      "blocks": [
        {
          "type": "section",
          "text": {
            "type": "mrkdwn",
            "text": "{{message}}"
          }
        },
        {
          "type": "section",
          "fields": [
            {
              "type": "mrkdwn",
              "text": "*Application*\n{{app}}"
            },
            {
              "type": "mrkdwn",
              "text": "*Environment*\n{{env}}"
            }
          ]
        },
        {
          "type": "section",
          "fields": [
            {
              "type": "mrkdwn",
              "text": "*Revision*\n<{{revision_url}}|{{revision_sha}}>"
            }
          ]
        },
        {
          "type": "context",
          "elements": [
            {
              "type": "mrkdwn",
              "text": "<{{log_url}}|View pipeline logs>"
            }
          ]
        }
      ]
    }
  secondary: |
    {"text": "{{message}}"}

Send notification

Fill in the channel name in the workflow below and submit it.

apiVersion: argoproj.io/v1alpha1
kind: Workflow
metadata:
  generateName: notifications-test-
spec:
  entrypoint: main
  templates:
    - name: main
      steps:
        - - name: setup-notifications
            template: hermes-setup

        - - name: pre-notification
            template: hermes-notify
            arguments:
              parameters:
                - name: message
                  value: "Deployment started :hourglass_flowing_sand:"

        - - name: hello
            template: hello

        - - name: post-notification
            template: hermes-notify
            arguments:
              parameters:
                - name: message
                  value: "Deployment succeeded :white_check_mark:"

    - name: hermes-setup
      plugin:
        hermes:
          setup:
            alias: default
            service: slack
            config:
              token: slack-token
              icon_emoji: ":rocket:"

    - name: hermes-notify
      inputs:
        parameters:
          - name: message
      plugin:
        hermes:
          notify:
            target: default
            template: hermes-template-slack-default
            config:
              channel: # Your Slack channel name goes here
            context:
              message: "{{inputs.parameters.message}}"
              app: hermes
              env: prod
              revision_sha: "deadbeef"
              revision_url: "https://google.com"
              log_url: "https://google.com"

    - name: hello
      container:
        image: docker/whalesay
        command: [cowsay]
        args: ["hello world"]

Reference

Setup config

Field	Required	Description
token	yes	The name of the secret containing the Slack OAuth token. The token has to be stored in the token field in the secret.
icon_emoji	no	A shortcode for the emoji to use as the bot avatar, e.g. :rocket.

Notify config

Field	Required	Description
channel	yes	The name of the channel to send the notification to, .e.g argo-alerts.