pkg/shelf

pkg/shelf/test/create_middleware_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 shelf.create_middleware_test;
+
+import 'dart:async';
+
+import 'package:shelf/shelf.dart';
+import 'package:unittest/unittest.dart';
+
+import 'test_util.dart';
+
+void main() {
+  test('forwards the request and response if both handlers are null', () {
+    var handler = const Stack()
+        .addMiddleware(createMiddleware())
+        .addHandler((request) {
+          return syncHandler(request, headers: {'from' : 'innerHandler'});
+        });
+
+    return makeSimpleRequest(handler).then((response) {
+      expect(response.headers['from'], 'innerHandler');
+    });
+  });
+
+  group('requestHandler', () {
+    test('sync null response forwards to inner handler', () {
+      var handler = const Stack()
+          .addMiddleware(createMiddleware(requestHandler: (request) => null))
+          .addHandler(syncHandler);
+
+      return makeSimpleRequest(handler).then((response) {
+        expect(response.headers['from'], isNull);
+      });
+    });
+
+    test('async null response forwards to inner handler', () {
+      var handler = const Stack()
+          .addMiddleware(createMiddleware(
+              requestHandler: (request) => new Future.value(null)))
+          .addHandler(syncHandler);
+
+      return makeSimpleRequest(handler).then((response) {
+        expect(response.headers['from'], isNull);
+      });
+    });
+
+    test('sync response is returned', () {
+      var handler = const Stack()
+          .addMiddleware(createMiddleware(
+              requestHandler: (request) => _middlewareResponse))
+          .addHandler(_failHandler);
+
+      return makeSimpleRequest(handler).then((response) {
+        expect(response.headers['from'], 'middleware');
+      });
+    });
+
+    test('async response is returned', () {
+      var handler = const Stack()
+          .addMiddleware(createMiddleware(requestHandler: (request) =>
+              new Future.value(_middlewareResponse)))
+          .addHandler(_failHandler);
+
+      return makeSimpleRequest(handler).then((response) {
+        expect(response.headers['from'], 'middleware');
+      });
+    });
+
+    group('with responseHandler', () {
+      test('with sync result, responseHandler is not called', () {
+        var middleware = createMiddleware(
+            requestHandler: (request) => _middlewareResponse,
+            responseHandler: (response) => fail('should not be called'));
+
+        var handler = const Stack()
+            .addMiddleware(middleware)
+            .addHandler(syncHandler);
+
+        return makeSimpleRequest(handler).then((response) {
+          expect(response.headers['from'], 'middleware');
+        });
+      });
+
+      test('with async result, responseHandler is not called', () {
+        var middleware = createMiddleware(
+            requestHandler: (request) => new Future.value(_middlewareResponse),
+            responseHandler: (response) => fail('should not be called'));
+        var handler = const Stack()
+            .addMiddleware(middleware)
+            .addHandler(syncHandler);
+
+        return makeSimpleRequest(handler).then((response) {
+          expect(response.headers['from'], 'middleware');
+        });
+      });
+    });
+  });
+
+  group('responseHandler', () {
+    test('innerHandler sync response is seen, replaced value continues', () {
+      var handler = const Stack().addMiddleware(createMiddleware(
+          responseHandler: (response) {
+        expect(response.headers['from'], 'handler');
+        return _middlewareResponse;
+      })).addHandler((request) {
+        return syncHandler(request, headers: {'from' : 'handler'} );
+      });
+
+      return makeSimpleRequest(handler).then((response) {
+        expect(response.headers['from'], 'middleware');
+      });
+    });
+
+    test('innerHandler async response is seen, async value continues', () {
+      var handler = const Stack().addMiddleware(
+          createMiddleware(responseHandler: (response) {
+        expect(response.headers['from'], 'handler');
+        return new Future.value(_middlewareResponse);
+      })).addHandler((request) {
+        return new Future(() => syncHandler(
+            request, headers: {'from' : 'handler'} ));
+      });
+
+      return makeSimpleRequest(handler).then((response) {
+        expect(response.headers['from'], 'middleware');
+      });
+    });
+  });
+
+  group('error handling', () {
+    test('sync error thrown by requestHandler bubbles down', () {
+      var handler = const Stack()
+          .addMiddleware(createMiddleware(
+              requestHandler: (request) => throw 'middleware error'))
+          .addHandler(_failHandler);
+
+      expect(makeSimpleRequest(handler), throwsA('middleware error'));
+    });
+
+    test('async error thrown by requestHandler bubbles down', () {
+      var handler = const Stack()
+          .addMiddleware(createMiddleware(requestHandler: (request) =>
+              new Future.error('middleware error')))
+          .addHandler(_failHandler);
+
+      expect(makeSimpleRequest(handler), throwsA('middleware error'));
+    });
+
+    test('throw from responseHandler does not hit error handler', () {
+      var middleware = createMiddleware(responseHandler: (response) {
+        throw 'middleware error';
+      }, errorHandler: (e, s) => fail('should never get here'));
+
+      var handler = const Stack().addMiddleware(middleware)
+          .addHandler(syncHandler);
+
+      expect(makeSimpleRequest(handler), throwsA('middleware error'));
+    });
+
+    test('requestHandler throw does not hit errorHandlers', () {
+      var middleware = createMiddleware(
+          requestHandler: (request) {
+            throw 'middleware error';
+          },
+          errorHandler: (e, s) => fail('should never get here'));
+
+      var handler = const Stack().addMiddleware(middleware)
+          .addHandler(syncHandler);
+
+      expect(makeSimpleRequest(handler), throwsA('middleware error'));
+    });
+
+    test('inner handler throws, is caught by errorHandler with response', () {
+      var middleware = createMiddleware(
+          errorHandler: (error, stack) {
+            expect(error, 'bad handler');
+            return _middlewareResponse;
+          });
+
+      var handler = const Stack().addMiddleware(middleware)
+          .addHandler((request) {
+        throw 'bad handler';
+      });
+
+      return makeSimpleRequest(handler).then((response) {
+        expect(response.headers['from'], 'middleware');
+      });
+    });
+
+    test('inner handler throws, is caught by errorHandler and rethrown', () {
+      var middleware = createMiddleware(errorHandler: (error, stack) {
+        expect(error, 'bad handler');
+        throw error;
+      });
+
+      var handler = const Stack().addMiddleware(middleware)
+          .addHandler((request) {
+        throw 'bad handler';
+      });
+
+      expect(makeSimpleRequest(handler), throwsA('bad handler'));
+    });
+  });
+}
+
+_failHandler(Request request) => fail('should never get here');
+
+final Response _middlewareResponse =
+    new Response.ok('middleware content', headers: {'from': 'middleware'});