Simple Activity Log by Collection for MeteorJS

activity.collection.js

/**
 * Example Document
 {
    _id  : 'xDvcFlsQws',
   activity : 'Project Created',
   createdAt : '1231213412312'
   collection : 'projects',
   documentId : 'xJ4iTyxDw2',
   userId : 'pQ4iTyxDw7'
 }
 * @type {Mongo.Collection}
 */
Activity = new Meteor.Collection('activity');

Activity.allow({
  'insert': function(userId, doc) {
    return true;
  },

  'update': function(userId, docs, fields, modifier) {
    return true;
  },

  'remove': function(userId, docs) {
    return true;
  }
});

Activity.before.insert(function (userId, doc) {
  //Check if the document has the required entries
  if(!doc.activity || !doc.collection || !doc.documentId)
    return false;

  //Only insert if ran on the server otherwise the server will deny the insert
  if(Meteor.isServer) {
    //Format the document
    doc.createdAt = Date.now();
    doc.userId = userId;
  } else {
   return false;
  }
});

Activity.helpers({

  /**
   * Gets the related document
   * @returns {any}
   */
  'getDocument': function () {
    return window[this.collection].findOne({ _id: this.documentId });
  },

  /**
   * Gets the user who performed the activity
   * @returns {any}
   */
  'getUser': function () {
    return window[this.collection].findOne({ _id: this.userId });
  }

});

example.usage.js

Projects.after.insert(function (userId, doc) {
  
  if(Meteor.isServer) {
    //Log the fact that a Project was created
    Activity.insert({
      'activity' : 'Project Created',
      'collection' : 'Projects',
      'documentId' : doc._id
    });
  }
  
});