Port Backend to SQLite/Sequelize (removes MongoDB), Support Electron (#14)

* The MongoDB/Mongoose data storage is removed in favor of Sequelize. This abstracts over SQLite or RDBMs like PostgreSQL and MSSQL. The default is SQLite, which significantly simplifies deployments in end-user environments.

* As Spacedeck now has no more mandatory server dependencies, we can wrap it in Electron and ship it as a desktop application.

* Removes docker-compose.yml

* First version of import UI

routes/api/space_messages.js

@@ -1,6 +1,9 @@
 "use strict";
 var config = require('config');
-require('../../models/schema');
+const db = require('../../models/db');
+const Sequelize = require('sequelize');
+const Op = Sequelize.Op;
+const uuidv4 = require('uuid/v4');
 
 var redis = require('../../helpers/redis');
 var mailer = require('../../helpers/mailer');
@@ -11,15 +14,12 @@ var phantom = require('../../helpers/phantom');
 var async = require('async');
 var fs = require('fs');
 var _ = require("underscore");
-var mongoose = require("mongoose");
 var archiver = require('archiver');
 var request = require('request');
 var url = require("url");
 var path = require("path");
 var crypto = require('crypto');
-var qr = require('qr-image');
 var glob = require('glob');
-var gm = require('gm');
 
 var express = require('express');
 var router = express.Router({mergeParams: true});
@@ -49,90 +49,44 @@ var roleMapping = {
 // MESSAGES
 
 router.get('/', function(req, res, next) {
-  Message.find({
-    space: req.space._id
-  }).populate('user', userMapping).exec(function(err, messages) {
-    res.status(200).json(messages);
-  });
+  db.Message.findAll({where:{
+    space_id: req.space._id
+  }, include: ['user']})
+    .then(function(messages) {
+      res.status(200).json(messages);
+    });
 });
 
 router.post('/', function(req, res, next) {
   var attrs = req.body;
-  attrs.space = req.space;
+  attrs.space_id = req.space._id;
 
   if (req.user) {
     attrs.user = req.user;
+    attrs.user_id = req.user._id;
   } else {
     attrs.user = null;
   }
 
-  var msg = new Message(attrs);
-  msg.save(function(err) {
-    if (err) res.status(400).json(erra);
-    else {
-      if (msg.message.length <= 1) return;
+  var msg = attrs;
+  msg._id = uuidv4();
 
-      Membership
-        .find({
-          space: req.space,
-          user: {
-            "$exists": true
-          }
-        })
-        .populate('user')
-        .exec(function(err, memberships) {
-          var users = memberships.map(function(m) {
-            return m.user;
-          });
-          users.forEach((user) => {
-            if (user.preferences.email_notifications) {
-              redis.isOnlineInSpace(user, req.space, function(err, online) {
-                if (!online) {
-                  var nickname = msg.editor_name;
-                  if (req.user) {
-                    nickname = req.user.nickname;
-                  }
-                  mailer.sendMail(
-                    user.email,
-                    req.i18n.__("space_message_subject", req.space.name),
-                    req.i18n.__("space_message_body", nickname, req.space.name), {
-                      message: msg.message,
-                      action: {
-                        link: config.endpoint + "/spaces/" + req.space._id.toString(),
-                        name: req.i18n.__("open")
-                      }
-                    });
-                } else {
-                  console.log("not sending message to user: is online.");
-                }
-              });
-            } else {
-              console.log("not sending message to user: is disabled notifications.");
-            }
-          });
-        });
-
-      res.distributeCreate("Message", msg);
-    }
+  db.Message.create(msg).then(function() {
+    if (msg.message.length <= 1) return;
+    // TODO reimplement notifications
+    res.distributeCreate("Message", msg);
   });
 });
 
 router.delete('/:message_id', function(req, res, next) {
-  Message.findOne({
+  db.Message.findOne({where:{
     "_id": req.params.message_id
-  }, function(err, msg) {
+  }}).then(function(msg) {
     if (!msg) {
       res.sendStatus(404);
     } else {
-      msg.remove(function(err) {
-        if (err) res.status(400).json(err);
-        else {
-          if (msg) {
-            res.distributeDelete("Message", msg);
-          } else {
-            res.sendStatus(404);
-          }
-        }
+      msg.destroy().then(function() {
+        res.distributeDelete("Message", msg);
       });
     }
   });