Adds a new Slack message when connecting a channel for posting

server/models/Integration.js

@@ -1,5 +1,6 @@
 // @flow
 import { DataTypes, sequelize } from '../sequelize';
+import events from '../events';
 
 const Integration = sequelize.define('integration', {
   id: {
@@ -32,4 +33,16 @@ Integration.associate = models => {
   });
 };
 
+Integration.addHook('afterCreate', async model => {
+  events.add({ name: 'integrations.create', model });
+});
+
+Integration.addHook('afterUpdate', model =>
+  events.add({ name: 'integrations.update', model })
+);
+
+Integration.addHook('afterDestroy', model =>
+  events.add({ name: 'integrations.delete', model })
+);
+
 export default Integration;

server/services/slack/index.js

@@ -1,13 +1,62 @@
 // @flow
 import type { Event } from '../../events';
-import { Document, Integration } from '../../models';
+import { Document, Integration, Collection } from '../../models';
 import { presentSlackAttachment } from '../../presenters';
 
-const Slack = {
-  on: async (event: Event) => {
-    if (event.name !== 'documents.publish' && event.name !== 'documents.update')
-      return;
+class Slack {
+  on = async (event: Event) => {
+    switch (event.name) {
+      case 'documents.publish':
+      case 'documents.update':
+        return this.documentUpdated(event);
+      case 'integrations.create':
+        return this.integrationCreated(event);
+      default:
+    }
+  };
 
+  integrationCreated = async (event: Event) => {
+    const integration = await Integration.findOne({
+      where: {
+        id: event.model.id,
+        service: 'slack',
+        type: 'post',
+      },
+      include: [
+        {
+          model: Collection,
+          required: true,
+          as: 'collection',
+        },
+      ],
+    });
+    if (!integration) return;
+
+    const collection = integration.collection;
+    if (!collection) return;
+
+    await fetch(integration.settings.url, {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify({
+        text: `👋 Hey there! When documents are published or updated in the *${
+          collection.name
+        }* collection on Outline they will be posted to this channel!`,
+        attachments: [
+          {
+            color: collection.color,
+            title: collection.name,
+            title_link: `${process.env.URL}${collection.getUrl()}`,
+            text: collection.description,
+          },
+        ],
+      }),
+    });
+  };
+
+  documentUpdated = async (event: Event) => {
     const document = await Document.findById(event.model.id);
     if (!document) return;
 
@@ -37,7 +86,7 @@ const Slack = {
         attachments: [presentSlackAttachment(document)],
       }),
     });
-  },
-};
+  };
+}
 
-export default Slack;
+export default new Slack();