Webhook / Integration Event bus (#499)

* First bash at an event bus for webhooks and integrations

* Refactoring

* poc

* Revert too wide ranging changes
Move to two-queues

server/models/Document.js

@@ -7,6 +7,7 @@ import Plain from 'slate-plain-serializer';
 
 import isUUID from 'validator/lib/isUUID';
 import { DataTypes, sequelize } from '../sequelize';
+import events from '../events';
 import parseTitle from '../../shared/utils/parseTitle';
 import Revision from './Revision';
 
@@ -204,6 +205,20 @@ Document.searchForUser = async (
   return _.sortBy(documents, doc => ids.indexOf(doc.id));
 };
 
+// Hooks
+
+Document.addHook('afterCreate', model =>
+  events.add({ name: 'documents.create', model })
+);
+
+Document.addHook('afterDestroy', model =>
+  events.add({ name: 'documents.delete', model })
+);
+
+Document.addHook('afterUpdate', model =>
+  events.add({ name: 'documents.update', model })
+);
+
 // Instance methods
 
 Document.prototype.getSummary = function() {