Adds schema caching capabilities (5s by default) (#2286)

* Adds schema caching capabilities (off by default)

* Use InMemoryCacheAdapter

* Uses proper adapter to generate a cache

* Fix bugs when running disabled cache

* nits

* nits

* Use options object instead of boolean

* Imrpove concurrency of loadSchema

* Adds testing with SCHEMA_CACHE_ON

* Use CacheController instead of generator

- Makes caching SchemaCache use a generated prefix
- Makes clearing the SchemaCache clear only the cached schema keys
- Enable cache by default (ttl 5s)

spec/ParseInstallation.spec.js

@@ -9,13 +9,19 @@ let Parse = require('parse/node').Parse;
 let rest = require('../src/rest');
 let request = require("request");
 
-let config = new Config('test');
-let database = config.database;
+let config;
+let database;
 let defaultColumns = require('../src/Controllers/SchemaController').defaultColumns;
 
 const installationSchema = { fields: Object.assign({}, defaultColumns._Default, defaultColumns._Installation) };
 
 describe('Installations', () => {
+
+  beforeEach(() => {
+    config = new Config('test');
+    database = config.database;
+  });
+
   it_exclude_dbs(['postgres'])('creates an android installation with ids', (done) => {
     var installId = '12345678-abcd-abcd-abcd-123456789abc';
     var device = 'android';

spec/PointerPermissions.spec.js

@@ -4,6 +4,11 @@ var Schema = require('../src/Controllers/SchemaController');
 var Config = require('../src/Config');
 
 describe('Pointer Permissions', () => {
+
+  beforeEach(() => {
+    new Config(Parse.applicationId).database.schemaCache.clear();
+  });
+
   it_exclude_dbs(['postgres'])('should work with find', (done) => {
     let config = new Config(Parse.applicationId);
     let user = new Parse.User();

spec/RestQuery.spec.js

@@ -9,11 +9,17 @@ var querystring = require('querystring');
 var request = require('request');
 var rp = require('request-promise');
 
-var config = new Config('test');
-let database = config.database;
+var config;
+let database;
 var nobody = auth.nobody(config);
 
 describe('rest query', () => {
+
+  beforeEach(() => {
+    config = new Config('test');
+    database = config.database;
+  });
+
   it('basic query', (done) => {
     rest.create(config, nobody, 'TestObject', {}).then(() => {
       return rest.find(config, nobody, 'TestObject', {});

spec/Schema.spec.js

@@ -4,7 +4,7 @@ var Config = require('../src/Config');
 var SchemaController = require('../src/Controllers/SchemaController');
 var dd = require('deep-diff');
 
-var config = new Config('test');
+var config;
 
 var hasAllPODobject = () => {
   var obj = new Parse.Object('HasAllPOD');
@@ -20,6 +20,10 @@ var hasAllPODobject = () => {
 };
 
 describe('SchemaController', () => {
+  beforeEach(() => {
+    config = new Config('test');
+  });
+
   it('can validate one object', (done) => {
     config.database.loadSchema().then((schema) => {
       return schema.validateObject('TestObject', {a: 1, b: 'yo', c: false});

spec/helper.js

@@ -59,7 +59,7 @@ var defaultConfiguration = {
     myoauth: {
       module: path.resolve(__dirname, "myoauth") // relative path as it's run from src
     }
-  },
+  }
 };
 
 let openConnections = {};

spec/schemas.spec.js

@@ -116,6 +116,11 @@ var masterKeyHeaders = {
 };
 
 describe('schemas', () => {
+
+  beforeEach(() => {
+     config.database.schemaCache.clear();
+  });
+
   it('requires the master key to get all schemas', (done) => {
     request.get({
       url: 'http://localhost:8378/1/schemas',