Add a Peer class to json_rpc_2.

pkg/json_rpc_2/test/peer_test.dart

+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library json_rpc_2.test.client.client_test;
+
+import 'dart:async';
+import 'dart:convert';
+
+import 'package:unittest/unittest.dart';
+import 'package:json_rpc_2/error_code.dart' as error_code;
+import 'package:json_rpc_2/json_rpc_2.dart' as json_rpc;
+
+void main() {
+  var incoming;
+  var outgoing;
+  var peer;
+  setUp(() {
+    var incomingController = new StreamController();
+    incoming = incomingController.sink;
+    var outgoingController = new StreamController();
+    outgoing = outgoingController.stream;
+    peer = new json_rpc.Peer.withoutJson(
+        incomingController.stream, outgoingController);
+  });
+
+  group("like a client,", () {
+    test("can send a message and receive a response", () {
+      expect(outgoing.first.then((request) {
+        expect(request, equals({
+          "jsonrpc": "2.0",
+          "method": "foo",
+          "params": {"bar": "baz"},
+          "id": 0
+        }));
+        incoming.add({
+          "jsonrpc": "2.0",
+          "result": "qux",
+          "id": 0
+        });
+      }), completes);
+
+      peer.listen();
+      expect(peer.sendRequest("foo", {"bar": "baz"}),
+          completion(equals("qux")));
+    });
+
+    test("can send a batch of messages and receive a batch of responses", () {
+      expect(outgoing.first.then((request) {
+        expect(request, equals([
+          {
+            "jsonrpc": "2.0",
+            "method": "foo",
+            "params": {"bar": "baz"},
+            "id": 0
+          },
+          {
+            "jsonrpc": "2.0",
+            "method": "a",
+            "params": {"b": "c"},
+            "id": 1
+          },
+          {
+            "jsonrpc": "2.0",
+            "method": "w",
+            "params": {"x": "y"},
+            "id": 2
+          }
+        ]));
+
+        incoming.add([
+          {
+            "jsonrpc": "2.0",
+            "result": "qux",
+            "id": 0
+          },
+          {
+            "jsonrpc": "2.0",
+            "result": "d",
+            "id": 1
+          },
+          {
+            "jsonrpc": "2.0",
+            "result": "z",
+            "id": 2
+          }
+        ]);
+      }), completes);
+
+      peer.listen();
+
+      peer.withBatch(() {
+        expect(peer.sendRequest("foo", {"bar": "baz"}),
+            completion(equals("qux")));
+        expect(peer.sendRequest("a", {"b": "c"}), completion(equals("d")));
+        expect(peer.sendRequest("w", {"x": "y"}), completion(equals("z")));
+      });
+    });
+  });
+
+  group("like a server,", () {
+    test("can receive a call and return a response", () {
+      expect(outgoing.first, completion(equals({
+        "jsonrpc": "2.0",
+        "result": "qux",
+        "id": 0
+      })));
+
+      peer.registerMethod("foo", (_) => "qux");
+      peer.listen();
+
+      incoming.add({
+        "jsonrpc": "2.0",
+        "method": "foo",
+        "params": {"bar": "baz"},
+        "id": 0
+      });
+    });
+
+    test("can receive a batch of calls and return a batch of responses", () {
+      expect(outgoing.first, completion(equals([
+        {
+          "jsonrpc": "2.0",
+          "result": "qux",
+          "id": 0
+        },
+        {
+          "jsonrpc": "2.0",
+          "result": "d",
+          "id": 1
+        },
+        {
+          "jsonrpc": "2.0",
+          "result": "z",
+          "id": 2
+        }
+      ])));
+
+      peer.registerMethod("foo", (_) => "qux");
+      peer.registerMethod("a", (_) => "d");
+      peer.registerMethod("w", (_) => "z");
+      peer.listen();
+
+      incoming.add([
+        {
+          "jsonrpc": "2.0",
+          "method": "foo",
+          "params": {"bar": "baz"},
+          "id": 0
+        },
+        {
+          "jsonrpc": "2.0",
+          "method": "a",
+          "params": {"b": "c"},
+          "id": 1
+        },
+        {
+          "jsonrpc": "2.0",
+          "method": "w",
+          "params": {"x": "y"},
+          "id": 2
+        }
+      ]);
+    });
+
+    test("returns a response for malformed JSON", () {
+      var incomingController = new StreamController();
+      var outgoingController = new StreamController();
+      var jsonPeer = new json_rpc.Peer(
+          incomingController.stream, outgoingController);
+
+      expect(outgoingController.stream.first.then(JSON.decode), completion({
+        "jsonrpc": "2.0",
+        "error": {
+          'code': error_code.PARSE_ERROR,
+          "message": startsWith("Invalid JSON: "),
+          "data": {'request': '{invalid'}
+        },
+        "id": null
+      }));
+
+      jsonPeer.listen();
+
+      incomingController.add("{invalid");
+    });
+
+    test("returns a response for incorrectly-structured JSON", () {
+      expect(outgoing.first, completion({
+        "jsonrpc": "2.0",
+        "error": {
+          'code': error_code.INVALID_REQUEST,
+          "message": 'Request must contain a "jsonrpc" key.',
+          "data": {'request': {'completely': 'wrong'}}
+        },
+        "id": null
+      }));
+
+      peer.listen();
+
+      incoming.add({
+        "completely": "wrong"
+      });
+    });
+  });
+}