Try to retrieve schema from all schemas cache if not found in individual cache (#2912)

* Try to get schema from main schema if not found in single schema

* Add newline

* Add missing return

* Add missing done to tests

spec/SchemaCache.spec.js

@@ -0,0 +1,37 @@
+var CacheController = require('../src/Controllers/CacheController.js').default;
+var InMemoryCacheAdapter = require('../src/Adapters/Cache/InMemoryCacheAdapter').default;
+var SchemaCache = require('../src/Controllers/SchemaCache').default;
+
+describe('SchemaCache', () => {
+	var schemaCache;
+
+	beforeEach(() => {
+		var cacheAdapter = new InMemoryCacheAdapter({});
+		var cacheController = new CacheController(cacheAdapter, 'appId');
+		schemaCache = new SchemaCache(cacheController);
+	});
+
+	it('can retrieve a single schema after all schemas stored', (done) => {
+		var allSchemas = [{
+			className: 'Class1'
+		}, {
+			className: 'Class2'
+		}];
+		schemaCache.setAllClasses(allSchemas);
+		schemaCache.getOneSchema('Class2').then((schema) => {
+			expect(schema).not.toBeNull();
+			done();
+		});
+	});
+
+	it('does not return all schemas after a single schema is stored', (done) => {
+		var schema = {
+			className: 'Class1'
+		};
+		schemaCache.setOneSchema('Class1', schema);
+		schemaCache.getAllClasses().then((allSchemas) => {
+			expect(allSchemas).toBeNull();
+			done();
+		});
+	});
+});

src/Controllers/SchemaCache.js

@@ -50,7 +50,21 @@ export default class SchemaCache {
     if (!this.ttl) {
       return Promise.resolve(null);
     }
-    return this.cache.get(this.prefix+className);
+    return this.cache.get(this.prefix+className).then((schema) => {
+      if (schema) {
+        return Promise.resolve(schema);
+      }
+      return this.cache.get(this.prefix+MAIN_SCHEMA).then((cachedSchemas) => {
+        cachedSchemas = cachedSchemas || [];
+        schema = cachedSchemas.find((cachedSchema) => {
+          return cachedSchema.className === className;
+        });
+        if (schema) {
+          return Promise.resolve(schema);
+        }
+        return Promise.resolve(null);
+      });
+    });
   }
 
   clear() {