Add new extension method for multipart/form-data

Author: justinyoo

src/Aliencube.AzureFunctions.Extensions.Common/ContentTypes.cs

@@ -24,5 +24,15 @@ public static class ContentTypes
         /// Identifies text/vnd.yaml.
         /// </summary>
         public const string TextVndYaml = "text/vnd.yaml";
+
+        /// <summary>
+        /// Identifies application/x-www-form-urlencoded.
+        /// </summary>
+        public const string ApplicationFormUrlEncoded = "application/x-www-form-urlencoded";
+
+        /// <summary>
+        /// Identifies multipart/form-data.
+        /// </summary>
+        public const string MultipartFormData = "multipart/form-data";
     }
 }

src/Aliencube.AzureFunctions.Extensions.Common/HttpRequestExtensions.cs

@@ -1,10 +1,10 @@
 using System;
-using System.Collections.Generic;
 using System.IO;
+using System.Linq;
+using System.Net.Http;
 using System.Threading.Tasks;
 
 using Microsoft.AspNetCore.Http;
-using Microsoft.Extensions.Primitives;
 
 using Newtonsoft.Json;
 
@@ -47,29 +47,48 @@ public static async Task<T> To<T>(this HttpRequest req, SourceFrom source = Sour
             return result;
         }
 
-        private static async Task<T> ToFromHeader<T>(this HttpRequest req)
+        /// <summary>
+        /// Converts the <see cref="HttpRequest"/> to the <see cref="MultipartFormDataContent"/> instance.
+        /// </summary>
+        /// <param name="req"><see cref="HttpRequest"/> instance.</param>
+        /// <returns>Returns the <see cref="MultipartFormDataContent"/> instance.</returns>
+        public static async Task<MultipartFormDataContent> ToMultipartFormDataContent(this HttpRequest req)
         {
-            if (!typeof(IEnumerable<KeyValuePair<string, StringValues>>).IsAssignableFrom(typeof(T)))
+            if (!req.Form.Files.Any())
             {
-                throw new InvalidOperationException(ExceptionMessages.InvalidType);
+                return null;
             }
 
-            var result = (T)req.Headers;
+            var mpfd = new MultipartFormDataContent();
+            foreach (var file in req.Form.Files)
+            {
+                var content = default(ByteArrayContent);
+                using (var ms = new MemoryStream())
+                {
+                    await file.CopyToAsync(ms).ConfigureAwait(false);
+                    content = new ByteArrayContent(ms.ToArray());
+                }
+
+                mpfd.Add(content, file.Name, file.FileName);
+            }
 
-            return await Task.FromResult(result).ConfigureAwait(false);
+            return mpfd;
         }
 
-        private static async Task<T> ToFromQuery<T>(this HttpRequest req)
+        private static async Task<T> ToFromHeader<T>(this HttpRequest req)
         {
-            var type = typeof(T);
-            if (!typeof(IEnumerable<KeyValuePair<string, StringValues>>).IsAssignableFrom(typeof(T)))
-            {
-                throw new InvalidOperationException(ExceptionMessages.InvalidType);
-            }
+            var serialised = JsonConvert.SerializeObject(req.Headers.ToDictionary(p => p.Key, p => p.Value.ToString()));
+            var deserialised = JsonConvert.DeserializeObject<T>(serialised);
 
-            var result = (T)req.Query;
+            return await Task.FromResult(deserialised).ConfigureAwait(false);
+        }
+
+        private static async Task<T> ToFromQuery<T>(this HttpRequest req)
+        {
+            var serialised = JsonConvert.SerializeObject(req.Query.ToDictionary(p => p.Key, p => p.Value.ToString()));
+            var deserialised = JsonConvert.DeserializeObject<T>(serialised);
 
-            return await Task.FromResult(result).ConfigureAwait(false);
+            return await Task.FromResult(deserialised).ConfigureAwait(false);
         }
 
         private static async Task<T> ToFromBody<T>(this HttpRequest req)

test/Aliencube.AzureFunctions.Extensions.Common.Tests/HttpRequestExtensionsTests.cs

@@ -2,8 +2,8 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.IO;
-using System.Linq;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
 
 using Aliencube.AzureFunctions.Extensions.Common.Tests.Models;
@@ -48,7 +48,7 @@ public void Given_InvalidType_When_To_Invoked_Then_It_Should_Throw_Exception(Sou
         }
 
         [DataTestMethod]
-        [DataRow("key1", "value1")]
+        [DataRow("x-secret-key", "hello-world")]
         public async Task Given_Header_When_To_Invoked_Then_It_Should_Return_Result(string key, string value)
         {
             var store = new Dictionary<string, StringValues>() { { key, value } };
@@ -57,15 +57,14 @@ public async Task Given_Header_When_To_Invoked_Then_It_Should_Return_Result(stri
             var req = new Mock<HttpRequest>();
             req.SetupGet(p => p.Headers).Returns(headers);
 
-            var result = await HttpRequestExtensions.To<IHeaderDictionary>(req.Object, SourceFrom.Header).ConfigureAwait(false);
+            var result = await HttpRequestExtensions.To<FakeRequestHeader>(req.Object, SourceFrom.Header).ConfigureAwait(false);
 
             result.Should().NotBeNull();
-            result.Should().HaveCount(store.Count);
-            result.Should().ContainKey(store.First().Key);
+            result.SecretKey.Should().Be(value);
         }
 
         [DataTestMethod]
-        [DataRow("key1", "value1")]
+        [DataRow("key", "value")]
         public async Task Given_Query_When_To_Invoked_Then_It_Should_Return_Result(string key, string value)
         {
             var store = new Dictionary<string, StringValues>() { { key, value } };
@@ -74,11 +73,10 @@ public async Task Given_Query_When_To_Invoked_Then_It_Should_Return_Result(strin
             var req = new Mock<HttpRequest>();
             req.SetupGet(p => p.Query).Returns(queries);
 
-            var result = await HttpRequestExtensions.To<IQueryCollection>(req.Object, SourceFrom.Query).ConfigureAwait(false);
+            var result = await HttpRequestExtensions.To<FakeRequestQuery>(req.Object, SourceFrom.Query).ConfigureAwait(false);
 
             result.Should().NotBeNull();
-            result.Should().HaveCount(store.Count);
-            result.Should().ContainKey(store.First().Key);
+            result.Key.Should().Be(value);
         }
 
         [DataTestMethod]
@@ -101,5 +99,46 @@ public async Task Given_Payload_When_To_Invoked_Then_It_Should_Return_Result(str
 
             await stream.DisposeAsync().ConfigureAwait(false);
         }
+
+        [TestMethod]
+        public async Task Given_Null_Payload_When_ToMultipartFormDataContent_Invoked_Then_It_Should_Return_Null()
+        {
+            var files = new FormFileCollection();
+
+            var form = new Mock<IFormCollection>();
+            form.SetupGet(p => p.Files).Returns(files);
+
+            var req = new Mock<HttpRequest>();
+            req.SetupGet(p => p.Form).Returns(form.Object);
+
+            var result = await HttpRequestExtensions.ToMultipartFormDataContent(req.Object).ConfigureAwait(false);
+
+            result.Should().BeNull();
+        }
+
+        [DataTestMethod]
+        [DataRow("hello", "world.jpg")]
+        public async Task Given_Payload_When_ToMultipartFormDataContent_Invoked_Then_It_Should_Return_Result(string name, string filename)
+        {
+            var file = new Mock<IFormFile>();
+            file.SetupGet(p => p.Name).Returns(name);
+            file.SetupGet(p => p.FileName).Returns(filename);
+            file.Setup(p => p.CopyToAsync(It.IsAny<Stream>(), It.IsAny<CancellationToken>())).Returns(Task.CompletedTask);
+
+            var files = new FormFileCollection
+            {
+                file.Object
+            };
+
+            var form = new Mock<IFormCollection>();
+            form.SetupGet(p => p.Files).Returns(files);
+
+            var req = new Mock<HttpRequest>();
+            req.SetupGet(p => p.Form).Returns(form.Object);
+
+            var result = await HttpRequestExtensions.ToMultipartFormDataContent(req.Object).ConfigureAwait(false);
+
+            result.Should().NotBeNull();
+        }
     }
 }

test/Aliencube.AzureFunctions.Extensions.Common.Tests/Models/FakeRequestHeader.cs

@@ -0,0 +1,10 @@
+using Newtonsoft.Json;
+
+namespace Aliencube.AzureFunctions.Extensions.Common.Tests.Models
+{
+    public class FakeRequestHeader
+    {
+        [JsonProperty("x-secret-key")]
+        public string? SecretKey { get; set; }
+    }
+}

test/Aliencube.AzureFunctions.Extensions.Common.Tests/Models/FakeRequestQuery.cs

@@ -0,0 +1,7 @@
+namespace Aliencube.AzureFunctions.Extensions.Common.Tests.Models
+{
+    public class FakeRequestQuery
+    {
+        public string? Key { get; set; }
+    }
+}