From 00846a0cece9d475bb0daee2b105008c8781bdc0 Mon Sep 17 00:00:00 2001
From: Gregory Schier <gschier1990@gmail.com>
Date: Mon, 31 Jul 2017 15:09:16 -0700
Subject: [PATCH] Support compressed resources for sync

---
 app/sync/index.js   | 23 ++++++++++++++++++++++-
 app/sync/storage.js |  4 ++--
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/app/sync/index.js b/app/sync/index.js
index 612532d98..8c2b6f2fb 100644
--- a/app/sync/index.js
+++ b/app/sync/index.js
@@ -6,6 +6,7 @@ import * as store from './storage';
 import * as misc from '../common/misc';
 import Logger from './logger';
 import {trackEvent} from '../analytics/index';
+import * as zlib from 'zlib';
 
 export const START_DELAY = 1E3;
 export const PULL_PERIOD = 15E3;
@@ -542,6 +543,7 @@ async function _handleChangeAndPush (event, doc, timestamp) {
  */
 const _fetchResourceGroupPromises = {};
 const _resourceGroupCache = {};
+
 export async function fetchResourceGroup (resourceGroupId, invalidateCache = false) {
   if (invalidateCache) {
     delete _resourceGroupCache[resourceGroupId];
@@ -630,7 +632,14 @@ async function _getResourceGroupSymmetricKey (resourceGroupId) {
 export async function encryptDoc (resourceGroupId, doc) {
   try {
     const symmetricKey = await _getResourceGroupSymmetricKey(resourceGroupId);
+
+    // TODO: Turn on compression once enough users are on version >= 5.7.0
+    // const jsonStr = JSON.stringify(doc);
+    // const docStr = zlib.gzipSync(jsonStr);
+
+    // Don't use compression for now
     const docStr = JSON.stringify(doc);
+
     const message = crypt.encryptAES(symmetricKey, docStr);
     return JSON.stringify(message);
   } catch (e) {
@@ -650,6 +659,12 @@ export async function decryptDoc (resourceGroupId, messageJSON) {
     throw e;
   }
 
+  try {
+    decrypted = zlib.gunzipSync(decrypted);
+  } catch (err) {
+    // It's not compressed (legacy), which is okay for now
+  }
+
   try {
     return JSON.parse(decrypted);
   } catch (e) {
@@ -730,7 +745,13 @@ export async function createResourceForDoc (doc) {
 }
 
 export async function getOrCreateResourceForDoc (doc) {
-  let resource = await store.getResourceByDocId(doc._id);
+  let [resource, ...extras] = await store.findResourcesByDocId(doc._id);
+
+  // Sometimes there may be multiple resources created by accident for
+  // the same doc. Let's delete the extras here if there are any.
+  for (const resource of extras) {
+    await store.removeResource(resource);
+  }
 
   if (resource) {
     return resource;
diff --git a/app/sync/storage.js b/app/sync/storage.js
index ab386832f..b04b2add7 100644
--- a/app/sync/storage.js
+++ b/app/sync/storage.js
@@ -99,12 +99,12 @@ export async function insertResource (resource) {
 
 export async function updateResource (resource, ...patches) {
   const newDoc = Object.assign({}, resource, ...patches);
-  await _execDB(TYPE_RESOURCE, 'update', {_id: resource._id}, newDoc);
+  await _execDB(TYPE_RESOURCE, 'update', {_id: resource._id}, newDoc, {multi: true});
   return newDoc;
 }
 
 export function removeResource (resource) {
-  return _execDB(TYPE_RESOURCE, 'remove', {_id: resource._id});
+  return _execDB(TYPE_RESOURCE, 'remove', {_id: resource._id}, {multi: true});
 }
 
 // ~~~~~~ //