Tests and tweaks for public node middleware

js/src/api/transport/jsonRpcBase.js

@@ -38,20 +38,20 @@ export default class JsonRpcBase extends EventEmitter {
     return json;
   }
 
-  addMiddleware (middleware) {
+  addMiddleware (Middleware) {
     this._middlewareList = Promise
       .all([
-        middleware,
+        Middleware,
         this._middlewareList
       ])
-      .then(([middleware, middlewareList]) => {
+      .then(([Middleware, middlewareList]) => {
         // Do nothing if `handlerPromise` resolves to a null-y value.
-        if (middleware == null) {
+        if (Middleware == null) {
           return middlewareList;
         }
 
         // don't mutate the original array
-        return middlewareList.concat([middleware]);
+        return middlewareList.concat([new Middleware(this)]);
       });
   }
 
@@ -80,8 +80,8 @@ export default class JsonRpcBase extends EventEmitter {
         const res = middleware.handle(method, params);
 
         if (res != null) {
-          // If `res` isn't a promise, we need to wrap it
-          return Promise.resolve(res)
+          return Promise
+            .resolve(res)
             .then((res) => {
               const result = this._wrapSuccessResult(res);
               const json = this.encode(method, params);

js/src/api/transport/middleware.js

@@ -28,9 +28,7 @@ export default class Middleware {
     const handler = this._handlers[method];
 
     if (handler != null) {
-      const response = handler(params);
-
-      return response;
+      return handler(params);
     }
 
     return null;

js/src/api/transport/middleware.spec.js

@@ -25,17 +25,21 @@ class MockTransport extends JsonRpcBase {
   }
 }
 
+class MockMiddleware extends Middleware {
+  constructor (transport) {
+    super(transport);
+
+    this.register('mock_rpc', ([num]) => num);
+    this.register('mock_null', () => null);
+  }
+}
+
 describe('api/transport/Middleware', () => {
-  let middleware;
   let transport;
 
   beforeEach(() => {
     transport = new MockTransport();
-    middleware = new Middleware(transport);
-
-    middleware.register('mock_rpc', ([num]) => num);
-    middleware.register('mock_null', () => null);
-    transport.addMiddleware(middleware);
+    transport.addMiddleware(MockMiddleware);
   });
 
   it('Routes requests to middleware', () => {