feat: slack app addon default channels (#4308)

https://linear.app/unleash/issue/2-1249/add-support-for-default-slack-channels

Adds support for default Slack channels (multiple, comma-separated). 

Some of the events we are handling do not have associated tags, or maybe
the tags are empty. This adds a "default Slack channels" parameter to
the addon configuration in order to post messages to those channels in
those cases.

<img width="643" alt="image"
src="https://github.com/Unleash/unleash/assets/14320932/ee23d6c7-33b7-4968-a0b1-13b546b5b2a2">

---------

Co-authored-by: Gastón Fournier <gaston@getunleash.io>

src/lib/addons/__snapshots__/slack-app.test.ts.snap

@@ -83,3 +83,45 @@ exports[`SlackAppAddon should post to all channels in tags 2`] = `
  "text": "some@user.com *enabled* <http://some-url.com/projects/default/features/some-toggle|some-toggle> in *development* environment in project *default*",
 }
 `;
+
+exports[`SlackAppAddon should use defaultChannels if no tagged channels are found 1`] = `
+{
+ "attachments": [
+ {
+ "actions": [
+ {
+ "name": "featureToggle",
+ "style": "primary",
+ "text": "Open in Unleash",
+ "type": "button",
+ "url": "http://some-url.com/projects/default/features/some-toggle",
+ "value": "featureToggle",
+ },
+ ],
+ },
+ ],
+ "channel": 1,
+ "text": "some@user.com *enabled* <http://some-url.com/projects/default/features/some-toggle|some-toggle> in *development* environment in project *default*",
+}
+`;
+
+exports[`SlackAppAddon should use defaultChannels if no tagged channels are found 2`] = `
+{
+ "attachments": [
+ {
+ "actions": [
+ {
+ "name": "featureToggle",
+ "style": "primary",
+ "text": "Open in Unleash",
+ "type": "button",
+ "url": "http://some-url.com/projects/default/features/some-toggle",
+ "value": "featureToggle",
+ },
+ ],
+ },
+ ],
+ "channel": 2,
+ "text": "some@user.com *enabled* <http://some-url.com/projects/default/features/some-toggle|some-toggle> in *development* environment in project *default*",
+}
+`;

src/lib/addons/slack-app-definition.ts

@@ -48,6 +48,15 @@ const slackAppDefinition: IAddonDefinition = {
  required: true,
  sensitive: true,
  },
+ {
+ name: 'defaultChannels',
+ displayName: 'Default channels',
+ description:
+ 'A comma-separated list of channels to post to if no tagged channels are found (e.g. a toggle without tags, or an event with no tags associated).',
+ type: 'text',
+ required: false,
+ sensitive: false,
+ },
  ],
  events: [
  FEATURE_CREATED,

src/lib/addons/slack-app.test.ts

@@ -79,6 +79,7 @@ describe('SlackAppAddon', () => {
  jest.useFakeTimers();
  slackApiCalls.length = 0;
  conversationsList.mockClear();
+ postMessage.mockClear();
  addon = new SlackAppAddon({
  getLogger,
  unleashUrl: 'http://some-url.com',
@@ -153,6 +154,37 @@ describe('SlackAppAddon', () => {
  expect(conversationsList).toHaveBeenCalledTimes(2);
  });
 
+ it('should not post a message if there are no tagged channels and no defaultChannels', async () => {
+ const eventWithoutTags: IEvent = {
+ ...event,
+ tags: [],
+ };
+
+ await addon.handleEvent(eventWithoutTags, {
+ accessToken,
+ });
+
+ expect(slackApiCalls.length).toBe(0);
+ });
+
+ it('should use defaultChannels if no tagged channels are found', async () => {
+ const eventWithoutTags: IEvent = {
+ ...event,
+ tags: [],
+ };
+
+ await addon.handleEvent(eventWithoutTags, {
+ accessToken,
+ defaultChannels: 'general, another-channel-1',
+ });
+
+ expect(slackApiCalls.length).toBe(2);
+ expect(slackApiCalls[0].channel).toBe(1);
+ expect(slackApiCalls[0]).toMatchSnapshot();
+ expect(slackApiCalls[1].channel).toBe(2);
+ expect(slackApiCalls[1]).toMatchSnapshot();
+ });
+
  it('should log error when an API call fails', async () => {
  postMessage = jest.fn().mockRejectedValue(mockError);
 

src/lib/addons/slack-app.ts

@@ -25,6 +25,7 @@ const CACHE_SECONDS = 30;
 
 interface ISlackAppAddonParameters {
  accessToken: string;
+ defaultChannels: string;
 }
 
 export default class SlackAppAddon extends Addon {
@@ -52,17 +53,20 @@ export default class SlackAppAddon extends Addon {
  parameters: ISlackAppAddonParameters,
  ): Promise<void> {
  try {
- const { accessToken } = parameters;
+ const { accessToken, defaultChannels } = parameters;
  if (!accessToken) {
  this.logger.warn('No access token provided.');
  return;
  }
 
  const taggedChannels = this.findTaggedChannels(event);
- if (!taggedChannels.length) {
+ const eventChannels = taggedChannels.length
+ ? taggedChannels
+ : this.getDefaultChannels(defaultChannels);
+
+ if (!eventChannels.length) {
  this.logger.debug(
- `No Slack channels tagged for event ${event.type}`,
- event,
+ `No Slack channels found for event ${event.type}.`,
  );
  return;
  }
@@ -99,7 +103,7 @@ export default class SlackAppAddon extends Addon {
  const url = this.msgFormatter.featureLink(event);
 
  const slackChannelsToPostTo = currentSlackChannels.filter(
- ({ id, name }) => id && name && taggedChannels.includes(name),
+ ({ id, name }) => id && name && eventChannels.includes(name),
  );
 
  const requests = slackChannelsToPostTo.map(({ id }) =>
@@ -151,6 +155,13 @@ export default class SlackAppAddon extends Addon {
  return [];
  }
 
+ getDefaultChannels(defaultChannels?: string): string[] {
+ if (defaultChannels) {
+ return defaultChannels.split(',').map((c) => c.trim());
+ }
+ return [];
+ }
+
  startCacheInvalidation(): void {
  this.slackChannelsCacheTimeout = setInterval(() => {
  this.slackChannels = undefined;