initial notification draft

- implements new notification manager using connect api - first use case of plugins using the plugin api
2026-08-12 12:30:39 +08:00 · 2018-02-09 18:17:25 -07:00
parent aaa1e0dbc3
commit 8b669a31c5
19 changed files with 570 additions and 0 deletions
@@ -0,0 +1,174 @@
+const { get, groupBy, forEach } = require('lodash');
+const debug = require('debug')('talk-plugin-notifications');
+const { graphql } = require('graphql');
+
+class NotificationManager {
+  constructor(context) {
+    this.context = context;
+    this.registry = [];
+  }
+
+  /**
+   * register will include the notification handlers on the manager.
+   *
+   * @param {Array<Object>} handlers notification handlers to register
+   */
+  register(...handlers) {
+    this.registry.push(...handlers);
+  }
+
+  /**
+   * attach will setup the notifications by walking the registry and loading all
+   * the notification types onto the handler.
+   *
+   * @param {Object} broker the event emitter for the Talk events
+   */
+  attach(broker) {
+    const events = groupBy(this.registry, 'event');
+
+    forEach(events, (handlers, event) => {
+      debug(
+        `will now notify the [${handlers
+          .map(({ category }) => category)
+          .join(', ')}] handlers when the '${event}' event is emitted`
+      );
+      broker.on(event, this.handle(handlers));
+    });
+  }
+
+  /**
+   * handle will wrap a notification handler and attach it to the notification
+   * stream system.
+   *
+   * @param {Object} handler a notification handler
+   */
+  handle(handlers) {
+    return async (...args) =>
+      Promise.all(
+        handlers.map(async handler => {
+          // Grab the handler reference.
+          const { handle } = handler;
+
+          // Create a system context to send down.
+          const ctx = this.context.forSystem();
+
+          try {
+            // Attempt to create a notification out of it.
+            const notification = await handle(ctx, ...args);
+            if (!notification) {
+              return;
+            }
+
+            // Extract the notification details.
+            const { userID, date, context } = notification;
+
+            // Send the notification.
+            return this.send(ctx, userID, date, handler, context);
+          } catch (err) {
+            // TODO: handle error.
+            return;
+          }
+        })
+      );
+  }
+
+  /**
+   *
+   * @param {Object} ctx graph context
+   * @param {String} userID the user id for the user being sent the email
+   */
+  async getEmail(ctx, userID) {
+    const { connectors: { graph: { schema } } } = ctx;
+
+    // Get the email for the user.
+    const reply = await graphql(
+      schema,
+      `
+        query GetUserEmail($userID: ID!) {
+          user(id: $userID) {
+            email
+          }
+        }
+      `,
+      {},
+      ctx,
+      { userID }
+    );
+    if (reply.errors) {
+      throw reply.errors;
+    }
+
+    return get(reply, 'data.user.email', null);
+  }
+
+  async send(ctx, userID, date, handler, context) {
+    const {
+      connectors: { services: { Mailer, I18n: { t } } },
+      loaders: { Settings },
+    } = ctx;
+    const { category } = handler;
+
+    try {
+      // Get the settings.
+      const { organizationName = null } = await Settings.load(
+        'organizationName'
+      );
+      if (organizationName === null) {
+        // TODO: handle error
+        return;
+      }
+
+      // Get the User's email.
+      const to = await this.getEmail(ctx, userID);
+      if (!to) {
+        // TODO: handle error
+        return;
+      }
+
+      // Compose the subject for the email.
+      const subject = t(
+        `talk-plugin-notifications.categories.${category}.subject`,
+        organizationName
+      );
+
+      // Load the content into the comment.
+      const body = await this.getBody(ctx, handler, context);
+
+      // Send the notification to the user.
+      const task = await Mailer.send({
+        template: 'notification',
+        locals: { body, organizationName },
+        subject,
+        to,
+      });
+
+      debug(`Sent the notification for Job.ID[${task.id}]`);
+    } catch (err) {
+      // TODO: print out the error.
+      return;
+    }
+  }
+
+  /**
+   * getBody will return the body for the notification payload.
+   *
+   * @param {Object} ctx the graph context
+   * @param {Object} handler the notification handler
+   * @param {Mixed} context the notification context
+   */
+  async getBody(ctx, handler, context) {
+    const { connectors: { services: { I18n: { t } } } } = ctx;
+    const { category } = handler;
+
+    // Get the body replacement variables for the translation key.
+    const replacements = await handler.hydrate(ctx, category, context);
+
+    // Generate the body.
+    return t(
+      `talk-plugin-notifications.categories.${category}.body`,
+      ...replacements
+    );
+  }
+}
+
+module.exports = NotificationManager;