[client-sync] Shim sequelize to timeout after 1 minute

Summary:
Sequelize can sometimes return promises that will never resolve or
reject. We can wrap the promises we get back from sequelize in a
bluebird promise which gives us the ability to timeout these abandoned
promises. This way, we can track down issues in sequelize as well as
unblocking stuck sync loops.

Test Plan: Run locally, verify that timeouts occur

Reviewers: juan, evan, spang

Reviewed By: evan

Differential Revision: https://phab.nylas.com/D4192

packages/client-sync/main.es6

@@ -1,8 +1,11 @@
 /* eslint global-require: 0 */
+import Sequelize from 'sequelize'; // eslint-disable-line
 import {ComponentRegistry} from 'nylas-exports'
 import {createLogger} from './src/shared/logger'
+import shimSequelize from './src/shared/shim-sequelize'
 
 export function activate() {
+  shimSequelize(Sequelize);
   global.Logger = createLogger()
   require('./src/local-api');
   require('./src/local-sync-worker');

packages/client-sync/src/shared/shim-sequelize.es6

@@ -0,0 +1,37 @@
+const _ = require('underscore');
+
+const DEFAULT_SEQUELIZE_SHIM_TIMEOUT = 60 * 1000; // 1 min
+
+const shimObject = (obj) => {
+  Object.keys(obj).forEach(key => {
+    // Skip internal methods.
+    if (key.startsWith('_')) {
+      return;
+    }
+
+    const prop = obj[key];
+    // Only patch methods.
+    if (!_.isFunction(prop)) {
+      return;
+    }
+
+    obj[key] = function(...args) {  // eslint-disable-line
+      const result = prop.call(this, ...args);
+      if (result && _.isFunction(result.then)) {
+        return new Promise(async (resolve, reject) => {
+          try {
+            resolve(await result);
+          } catch (err) {
+            reject(err);
+          }
+        }).timeout(DEFAULT_SEQUELIZE_SHIM_TIMEOUT, `${key} timed out`);
+      }
+      return result;
+    };
+  });
+};
+
+export default function shimSequelize(Sequelize) {
+  shimObject(Sequelize.Model);
+  shimObject(Sequelize.Instance.prototype);
+}