Merge pull request #3 from twitchax/context_fix

Pass HttpContext into lambda.

src/Core/AspNetCore.Proxy.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <Version>1.2.2</Version>
+    <Version>1.3.0</Version>
     <AssemblyName>AspNetCore.Proxy</AssemblyName>
     <PackageId>AspNetCore.Proxy</PackageId>
     <DocumentationFile>bin\AspNetCore.Proxy.xml</DocumentationFile>

src/Core/ProxyRouteExtensions.cs

@@ -28,8 +28,8 @@ public static void UseProxies(this IApplicationBuilder app)
                 var attribute = method.GetCustomAttributes(typeof(ProxyRouteAttribute), false).First() as ProxyRouteAttribute;
                 var parameters = method.GetParameters();
 
-                if(!(method.ReturnType == typeof(Task<string>)))
-                    throw new InvalidOperationException($"Proxied generator method ({name}) must return a Task<string>.");
+                if(method.ReturnType != typeof(Task<string>) && method.ReturnType != typeof(string))
+                    throw new InvalidOperationException($"Proxied generator method ({name}) must return a `Task<string>` or `string`.");
 
                 if(!method.IsStatic)
                     throw new InvalidOperationException($"Proxied generator method ({name}) must be static.");
@@ -49,7 +49,12 @@ public static void UseProxies(this IApplicationBuilder app)
                         }
                     });
 
-                    return method.Invoke(null, castedArgs.ToArray()) as Task<string>;
+                    // Make sure to always return a `Task<string>`, but allow methods that just return a `string`.
+                    
+                    if(method.ReturnType == typeof(Task<string>))
+                        return method.Invoke(null, castedArgs.ToArray()) as Task<string>;
+
+                    return Task.FromResult(method.Invoke(null, castedArgs.ToArray()) as string);
                 });
             }
         }
@@ -59,16 +64,16 @@ public static void UseProxies(this IApplicationBuilder app)
         /// </summary>
         /// <param name="app">The ASP.NET <see cref="IApplicationBuilder"/>.</param>
         /// <param name="endpoint">The local route endpoint.</param>
-        /// <param name="getProxiedAddress">A functor which returns the address to which the request is proxied.</param>
-        /// <param name="onFailure">A catch all for failures.</param>
-        public static void UseProxy(this IApplicationBuilder app, string endpoint, Func<IDictionary<string, object>, Task<string>> getProxiedAddress, Func<HttpContext, Exception, Task> onFailure = null)
+        /// <param name="getProxiedAddress">A lambda { (context, args) => Task[string] } which returns the address to which the request is proxied.</param>
+        /// <param name="onFailure">A lambda to handle proxy failures { (context, exception) => Task }.</param>
+        public static void UseProxy(this IApplicationBuilder app, string endpoint, Func<HttpContext, IDictionary<string, object>, Task<string>> getProxiedAddress, Func<HttpContext, Exception, Task> onFailure = null)
         {
             app.UseRouter(builder => {
                 builder.MapMiddlewareRoute(endpoint, proxyApp => {
                     proxyApp.Run(async context => {
                         try
                         {
-                            var proxiedAddress = await getProxiedAddress(context.GetRouteData().Values.ToDictionary(v => v.Key, v => v.Value)).ConfigureAwait(false);
+                            var proxiedAddress = await getProxiedAddress(context, context.GetRouteData().Values.ToDictionary(v => v.Key, v => v.Value)).ConfigureAwait(false);
                             var proxiedResponse = await context.SendProxyHttpRequest(proxiedAddress).ConfigureAwait(false);
                             
                             await context.CopyProxyHttpResponse(proxiedResponse).ConfigureAwait(false);
@@ -89,5 +94,91 @@ public static void UseProxy(this IApplicationBuilder app, string endpoint, Func<
                 });
             });
         }
+
+        #region UseProxy Overloads
+
+        /// <summary>
+        /// Middleware which creates an ad hoc proxy over a specified endpoint.
+        /// </summary>
+        /// <param name="app">The ASP.NET <see cref="IApplicationBuilder"/>.</param>
+        /// <param name="endpoint">The local route endpoint.</param>
+        /// <param name="getProxiedAddress">A lambda { (args) => Task[string] } which returns the address to which the request is proxied.</param>
+        /// <param name="onFailure">A lambda to handle proxy failures { (context, exception) => Task }.</param>
+        public static void UseProxy(this IApplicationBuilder app, string endpoint, Func<IDictionary<string, object>, Task<string>> getProxiedAddress, Func<HttpContext, Exception, Task> onFailure = null)
+        {
+            Func<HttpContext, IDictionary<string, object>, Task<string>> gpa = (context, args) => getProxiedAddress(args);
+
+            UseProxy(app, endpoint, gpa, onFailure);
+        }
+
+        /// <summary>
+        /// Middleware which creates an ad hoc proxy over a specified endpoint.
+        /// </summary>
+        /// <param name="app">The ASP.NET <see cref="IApplicationBuilder"/>.</param>
+        /// <param name="endpoint">The local route endpoint.</param>
+        /// <param name="getProxiedAddress">A lambda { () => Task[string] } which returns the address to which the request is proxied.</param>
+        /// <param name="onFailure">A lambda to handle proxy failures { (context, exception) => Task }.</param>
+        public static void UseProxy(this IApplicationBuilder app, string endpoint, Func<Task<string>> getProxiedAddress, Func<HttpContext, Exception, Task> onFailure = null)
+        {
+            Func<HttpContext, IDictionary<string, object>, Task<string>> gpa = (context, args) => getProxiedAddress();
+
+            UseProxy(app, endpoint, gpa, onFailure);
+        }
+
+        /// <summary>
+        /// Middleware which creates an ad hoc proxy over a specified endpoint.
+        /// </summary>
+        /// <param name="app">The ASP.NET <see cref="IApplicationBuilder"/>.</param>
+        /// <param name="endpoint">The local route endpoint.</param>
+        /// <param name="getProxiedAddress">A lambda { (context, args) => string } which returns the address to which the request is proxied.</param>
+        /// <param name="onFailure">A lambda to handle proxy failures { (context, exception) => void }.</param>
+        public static void UseProxy(this IApplicationBuilder app, string endpoint, Func<HttpContext, IDictionary<string, object>, string> getProxiedAddress, Action<HttpContext, Exception> onFailure = null)
+        {
+            Func<HttpContext, IDictionary<string, object>, Task<string>> gpa = (context, args) => Task.FromResult(getProxiedAddress(context, args));
+
+            Func<HttpContext, Exception, Task> of = null;
+            if(onFailure != null)
+                of = (context, e) => { onFailure(context, e); return Task.FromResult(0); };
+
+            UseProxy(app, endpoint, gpa, of);
+        }
+
+        /// <summary>
+        /// Middleware which creates an ad hoc proxy over a specified endpoint.
+        /// </summary>
+        /// <param name="app">The ASP.NET <see cref="IApplicationBuilder"/>.</param>
+        /// <param name="endpoint">The local route endpoint.</param>
+        /// <param name="getProxiedAddress">A lambda { (args) => string } which returns the address to which the request is proxied.</param>
+        /// <param name="onFailure">A lambda to handle proxy failures { (context, exception) => void }.</param>
+        public static void UseProxy(this IApplicationBuilder app, string endpoint, Func<IDictionary<string, object>, string> getProxiedAddress, Action<HttpContext, Exception> onFailure = null)
+        {
+            Func<HttpContext, IDictionary<string, object>, Task<string>> gpa = (context, args) => Task.FromResult(getProxiedAddress(args));
+
+            Func<HttpContext, Exception, Task> of = null;
+            if(onFailure != null)
+                of = (context, e) => { onFailure(context, e); return Task.FromResult(0); };
+
+            UseProxy(app, endpoint, gpa, of);
+        }
+
+        /// <summary>
+        /// Middleware which creates an ad hoc proxy over a specified endpoint.
+        /// </summary>
+        /// <param name="app">The ASP.NET <see cref="IApplicationBuilder"/>.</param>
+        /// <param name="endpoint">The local route endpoint.</param>
+        /// <param name="getProxiedAddress">A lambda { () => string } which returns the address to which the request is proxied.</param>
+        /// <param name="onFailure">A lambda to handle proxy failures { (context, exception) => void }.</param>
+        public static void UseProxy(this IApplicationBuilder app, string endpoint, Func<string> getProxiedAddress, Action<HttpContext, Exception> onFailure = null)
+        {
+            Func<HttpContext, IDictionary<string, object>, Task<string>> gpa = (context, args) => Task.FromResult(getProxiedAddress());
+
+            Func<HttpContext, Exception, Task> of = null;
+            if(onFailure != null)
+                of = (context, e) => { onFailure(context, e); return Task.FromResult(0); };
+
+            UseProxy(app, endpoint, gpa, of);
+        }
+
+        #endregion
     }
 }

src/Test/UnitTests.cs

@@ -23,19 +23,79 @@ public UnitTests()
         }
 
         [Fact]
-        public async Task ProxyAttribute()
+        public async Task ProxyAttributeToTask()
         {
-            var response = await _client.GetAsync("api/posts/1");
+            var response = await _client.GetAsync("api/posts/totask/1");
             response.EnsureSuccessStatusCode();
 
             var responseString = await response.Content.ReadAsStringAsync();
             Assert.Contains("sunt aut facere repellat provident occaecati excepturi optio reprehenderit", JObject.Parse(responseString).Value<string>("title"));
         }
 
         [Fact]
-        public async Task ProxyMiddleware()
+        public async Task ProxyAttributeToString()
         {
-            var response = await _client.GetAsync("api/comments/1");
+            var response = await _client.GetAsync("api/posts/tostring/1");
+            response.EnsureSuccessStatusCode();
+
+            var responseString = await response.Content.ReadAsStringAsync();
+            Assert.Contains("sunt aut facere repellat provident occaecati excepturi optio reprehenderit", JObject.Parse(responseString).Value<string>("title"));
+        }
+
+        [Fact]
+        public async Task ProxyMiddlewareWithContextAndArgsToTask()
+        {
+            var response = await _client.GetAsync("api/comments/contextandargstotask/1");
+            response.EnsureSuccessStatusCode();
+
+            var responseString = await response.Content.ReadAsStringAsync();
+            Assert.Contains("id labore ex et quam laborum", JObject.Parse(responseString).Value<string>("name"));
+        }
+
+        [Fact]
+        public async Task ProxyMiddlewareWithArgsToTask()
+        {
+            var response = await _client.GetAsync("api/comments/argstotask/1");
+            response.EnsureSuccessStatusCode();
+
+            var responseString = await response.Content.ReadAsStringAsync();
+            Assert.Contains("id labore ex et quam laborum", JObject.Parse(responseString).Value<string>("name"));
+        }
+
+        [Fact]
+        public async Task ProxyMiddlewareWithEmptyToTask()
+        {
+            var response = await _client.GetAsync("api/comments/emptytotask");
+            response.EnsureSuccessStatusCode();
+
+            var responseString = await response.Content.ReadAsStringAsync();
+            Assert.Contains("id labore ex et quam laborum", JObject.Parse(responseString).Value<string>("name"));
+        }
+
+        [Fact]
+        public async Task ProxyMiddlewareWithContextAndArgsToString()
+        {
+            var response = await _client.GetAsync("api/comments/contextandargstostring/1");
+            response.EnsureSuccessStatusCode();
+
+            var responseString = await response.Content.ReadAsStringAsync();
+            Assert.Contains("id labore ex et quam laborum", JObject.Parse(responseString).Value<string>("name"));
+        }
+
+        [Fact]
+        public async Task ProxyMiddlewareWithArgsToString()
+        {
+            var response = await _client.GetAsync("api/comments/argstostring/1");
+            response.EnsureSuccessStatusCode();
+
+            var responseString = await response.Content.ReadAsStringAsync();
+            Assert.Contains("id labore ex et quam laborum", JObject.Parse(responseString).Value<string>("name"));
+        }
+
+        [Fact]
+        public async Task ProxyMiddlewareWithEmptyToString()
+        {
+            var response = await _client.GetAsync("api/comments/emptytostring");
             response.EnsureSuccessStatusCode();
 
             var responseString = await response.Content.ReadAsStringAsync();
@@ -54,18 +114,46 @@ public void Configure(IApplicationBuilder app, IHostingEnvironment env)
         {
             app.UseProxies();
 
-            app.UseProxy("api/comments/{postId}", (args) => {
+            app.UseProxy("api/comments/contextandargstotask/{postId}", (context, args) => {
+                context.GetHashCode();
+                return Task.FromResult($"https://jsonplaceholder.typicode.com/comments/{args["postId"]}");
+            });
+
+            app.UseProxy("api/comments/argstotask/{postId}", (args) => {
                 return Task.FromResult($"https://jsonplaceholder.typicode.com/comments/{args["postId"]}");
             });
+
+            app.UseProxy("api/comments/emptytotask", () => {
+                return Task.FromResult($"https://jsonplaceholder.typicode.com/comments/1");
+            });
+
+            app.UseProxy("api/comments/contextandargstostring/{postId}", (context, args) => {
+                context.GetHashCode();
+                return $"https://jsonplaceholder.typicode.com/comments/{args["postId"]}";
+            });
+
+            app.UseProxy("api/comments/argstostring/{postId}", (args) => {
+                return $"https://jsonplaceholder.typicode.com/comments/{args["postId"]}";
+            });
+
+            app.UseProxy("api/comments/emptytostring", () => {
+                return $"https://jsonplaceholder.typicode.com/comments/1";
+            });
         }
     }
 
     public static class UseProxies
     {
-        [ProxyRoute("api/posts/{postId}")]
-        public static  Task<string> ProxyGoogle(int postId)
+        [ProxyRoute("api/posts/totask/{postId}")]
+        public static Task<string> ProxyGoogleToTask(int postId)
         {
             return Task.FromResult($"https://jsonplaceholder.typicode.com/posts/{postId}");
         }
+
+        [ProxyRoute("api/posts/tostring/{postId}")]
+        public static string ProxyGoogleToString(int postId)
+        {
+            return $"https://jsonplaceholder.typicode.com/posts/{postId}";
+        }
     }
 }