initial impl of cached action counts using ee

.vscode/settings.json

@@ -0,0 +1,8 @@
+{
+  "eslint.autoFixOnSave": true,
+  "editor.tabSize": 2,
+  "editor.rulers": [
+      80
+  ],
+  "files.trimTrailingWhitespace": true
+}

graph/mutators/action.js

@@ -1,4 +1,3 @@
-const ActionModel = require('../../models/action');
 const ActionsService = require('../../services/actions');
 const UsersService = require('../../services/users');
 const errors = require('../../errors');
@@ -52,10 +51,7 @@ const createAction = async ({user = {}, pubsub, loaders: {Comments}}, {item_id,
  * @return {Promise}     resolves to the deleted action, or null if not found.
  */
 const deleteAction = ({user}, {id}) => {
-  return ActionModel.findOneAndRemove({
-    id,
-    user_id: user.id
-  });
+  return ActionsService.delete({id, user_id: user.id});
 };
 
 module.exports = (context) => {

models/comment.js

@@ -66,15 +66,23 @@ const CommentSchema = new Schema({
     enum: COMMENT_STATUS,
     default: 'NONE'
   },
+
+  // parent_id is the id of the parent comment (null if there is none).
   parent_id: String,
 
+  // Counts to store related to actions taken on the given comment.
+  action_counts: {
+    default: {},
+    type: Object,
+  },
+
   // Tags are added by the self or by administrators.
   tags: [TagLinkSchema],
 
   // Additional metadata stored on the field.
   metadata: {
     default: {},
-    type: Object
+    type: Object,
   }
 }, {
   timestamps: {

services/actions.js

@@ -1,6 +1,30 @@
 const ActionModel = require('../models/action');
 const _ = require('lodash');
 const errors = require('../errors');
+const events = require('./events');
+
+const findOneAndUpdate = async (query, update, options = {}) => new Promise((resolve, reject) => {
+  ActionModel.findOneAndUpdate(query, update, Object.assign({}, options, {
+
+    // Use raw result to get `updatedExisting`.
+    passRawResult: true,
+
+    // Ensure that if it's new, we return the new object created.
+    new: true,
+
+    // Perform an upsert in the event that this doesn't exist.
+    upsert: true,
+
+    // Set the default values if not provided based on the mongoose models.
+    setDefaultsOnInsert: true
+  }), (err, doc, raw) => {
+    if (err) { return reject(err); }
+    if (raw.lastErrorObject.updatedExisting) {
+      return reject(new errors.ErrAlreadyExists(raw.value));
+    }
+    return resolve(raw.value);
+  });
+});
 
 module.exports = class ActionsService {
 
@@ -19,46 +43,26 @@ module.exports = class ActionsService {
    * @param {String} action   the new action to the item
    * @return {Promise}
    */
-  static insertUserAction(action) {
+  static async insertUserAction(action) {
 
     // Actions are made unique by using a query that can be reproducable, i.e.,
     // not containing user inputable values.
-    let query = {
+    let foundAction = await findOneAndUpdate({
       action_type: action.action_type,
       item_type: action.item_type,
       item_id: action.item_id,
       user_id: action.user_id,
-      group_id: action.group_id
-    };
+      group_id: action.group_id,
+    }, {
 
-    // Create/Update the action.
-    return new Promise((resolve, reject) => {
-      ActionModel.findOneAndUpdate(
-        query, {
-
-          // Only set when not existing.
-          $setOnInsert: action,
-        }, {
-
-          // Ensure that if it's new, we return the new object created.
-          new: true,
-
-          // Use raw result to get `updatedExisting`.
-          passRawResult: true,
-
-          // Perform an upsert in the event that this doesn't exist.
-          upsert: true,
-
-          // Set the default values if not provided based on the mongoose models.
-          setDefaultsOnInsert: true
-        }, (err, doc, raw) => {
-          if (err) { return reject(err); }
-          if (raw.lastErrorObject.updatedExisting) {
-            return reject(new errors.ErrAlreadyExists(raw.value));
-          }
-          return resolve(raw.value);
-        });
+      // Only set when not existing.
+      $setOnInsert: action,
     });
+
+    // Emit that there was a new action created.
+    events.emit('actions.new', foundAction);
+
+    return foundAction;
   }
 
   /**
@@ -190,6 +194,21 @@ module.exports = class ActionsService {
     });
   }
 
+  static async delete({id, user_id}) {
+    let action = await ActionModel.findOneAndRemove({
+      id,
+      user_id,
+    });
+    if (!action) {
+      return;
+    }
+
+    // Emit that the action was deleted.
+    events.emit('actions.delete', action);
+
+    return action;
+  }
+
   /**
    * Finds all comments ids for a specific action.
    * @param {String} action_type type of action

services/comments.js

@@ -5,6 +5,49 @@ const ActionsService = require('./actions');
 const SettingsService = require('./settings');
 
 const errors = require('../errors');
+const events = require('./events');
+
+// When a new action is created, modify the comment.
+events.on('actions.new', async (action) => {
+  if (!action || action.item_type !== 'COMMENTS') {
+    return;
+  }
+
+  const ACTION_TYPE = action.action_type.toLowerCase();
+
+  try {
+    await CommentModel.update({
+      id: action.item_id,
+    }, {
+      $inc: {
+        [`action_counts.${ACTION_TYPE}`]: 1,
+      }
+    });
+  } catch (err) {
+    console.error(`Can't increment the action_counts.${ACTION_TYPE}:`, err);
+  }
+});
+
+// When an action is deleted, modify the comment.
+events.on('actions.delete', async (action) => {
+  if (!action || action.item_type !== 'COMMENTS') {
+    return;
+  }
+
+  const ACTION_TYPE = action.action_type.toLowerCase();
+
+  try {
+    await CommentModel.update({
+      id: action.item_id,
+    }, {
+      $inc: {
+        [`action_counts.${ACTION_TYPE}`]: -1,
+      }
+    });
+  } catch (err) {
+    console.error(`Can't decrement the action_counts.${ACTION_TYPE}:`, err);
+  }
+});
 
 module.exports = class CommentsService {
 

services/events.js

@@ -0,0 +1,17 @@
+const {EventEmitter2} = require('eventemitter2');
+const debug = require('debug')('talk:services:events');
+const enabled = require('debug').enabled('talk:services:events');
+
+const events = new EventEmitter2({
+  wildcard: true,
+});
+
+// If event debugging is enabled, bind the debugger to all events being emitted
+// and log a debug message.
+if (enabled) {
+  events.onAny(function(event) {
+    debug(`[${event}] ${arguments.length - 1} argument${arguments.length - 1 === 1 ? '' : 's'}`);
+  });
+}
+
+module.exports = events;