refactor(rest): create providers for send and parse-params

packages/rest/src/providers/index.ts

@@ -9,3 +9,5 @@ export * from './get-from-context';
 export * from './invoke-method';
 export * from './log-error-provider';
 export * from './reject';
+export * from './parse-params';
+export * from './send';

packages/rest/src/providers/parse-params.ts

@@ -0,0 +1,20 @@
+// Copyright IBM Corp. 2017. All Rights Reserved.
+// Node module: @loopback/rest
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {Provider, BoundValue} from '@loopback/context';
+import {parseOperationArgs} from '../parser';
+/**
+ * Provides the function for parsing args in requests at runtime.
+ *
+ * @export
+ * @class ParseParamsProvider
+ * @implements {Provider<BoundValue>}
+ * @returns {BoundValue} The handler function that will parse request args.
+ */
+export class ParseParamsProvider implements Provider<BoundValue> {
+  value() {
+    return parseOperationArgs;
+  }
+}

packages/rest/src/providers/send.ts

@@ -0,0 +1,22 @@
+// Copyright IBM Corp. 2017. All Rights Reserved.
+// Node module: @loopback/rest
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {Provider, BoundValue} from '@loopback/context';
+import {writeResultToResponse} from '../writer';
+/**
+ * Provides the function that populates the response object with
+ * the results of the operation.
+ *
+ * @export
+ * @class SendProvider
+ * @implements {Provider<BoundValue>}
+ * @returns {BoundValue} The handler function that will populate the
+ * response with operation results.
+ */
+export class SendProvider implements Provider<BoundValue> {
+  value() {
+    return writeResultToResponse;
+  }
+}

packages/rest/src/rest-component.ts

@@ -27,6 +27,8 @@ import {
   GetFromContextProvider,
   InvokeMethodProvider,
   RejectProvider,
+  ParseParamsProvider,
+  SendProvider,
 } from './providers';
 import {RestServer, RestServerConfig} from './rest-server';
 
@@ -38,6 +40,8 @@ export class RestComponent implements Component {
     [RestBindings.SequenceActions.REJECT]: RejectProvider,
     [RestBindings.BIND_ELEMENT]: BindElementProvider,
     [RestBindings.GET_FROM_CONTEXT]: GetFromContextProvider,
+    [RestBindings.SequenceActions.PARSE_PARAMS]: ParseParamsProvider,
+    [RestBindings.SequenceActions.SEND]: SendProvider,
   };
   servers: Constructor<Server>[] = [];
   constructor(

packages/rest/src/rest-server.ts

@@ -126,8 +126,6 @@ export class RestServer extends Context implements Server {
     };
 
     this.bind(RestBindings.HANDLER).toDynamicValue(() => this.httpHandler);
-    this.bind(SequenceActions.PARSE_PARAMS).to(parseOperationArgs);
-    this.bind(SequenceActions.SEND).to(writeResultToResponse);
   }
 
   protected _handleHttpRequest(