Implement support for HTTP file download for SendHttpRequest and Writ…

…eHttpResponse

src/activities/Elsa.Activities.Http/Activities/SendHttpRequest/SendHttpRequest.cs

@@ -29,11 +29,11 @@ namespace Elsa.Activities.Http
     public class SendHttpRequest : Activity
     {
         private readonly HttpClient _httpClient;
-        private readonly IEnumerable<IHttpResponseBodyParser> _parsers;
+        private readonly IEnumerable<IHttpResponseContentReader> _parsers;
 
         public SendHttpRequest(
             IHttpClientFactory httpClientFactory,
-            IEnumerable<IHttpResponseBodyParser> parsers)
+            IEnumerable<IHttpResponseContentReader> parsers)
         {
             _httpClient = httpClientFactory.CreateClient(nameof(SendHttpRequest));
             _parsers = parsers;
@@ -68,7 +68,7 @@ public class SendHttpRequest : Activity
         [ActivityInput(
             UIHint = ActivityInputUIHints.Dropdown,
             Hint = "The content type to send with the request.",
-            Options = new[] { "text/plain", "text/html", "application/json", "application/xml", "application/x-www-form-urlencoded" },
+            Options = new[] { "", "text/plain", "text/html", "application/json", "application/xml", "application/x-www-form-urlencoded" },
             SupportedSyntaxes = new[] { SyntaxNames.JavaScript, SyntaxNames.Liquid }
         )]
         public string? ContentType { get; set; }
@@ -102,7 +102,7 @@ public class SendHttpRequest : Activity
         )]
         public ICollection<int>? SupportedStatusCodes { get; set; } = new HashSet<int>(new[] { 200 });
 
-        [ActivityOutput] public HttpResponseModel Output { get; set; }
+        [ActivityOutput] public HttpResponseModel? Output { get; set; }
 
         protected override async ValueTask<IActivityExecutionResult> OnExecuteAsync(ActivityExecutionContext context)
         {
@@ -122,8 +122,8 @@ protected override async ValueTask<IActivityExecutionResult> OnExecuteAsync(Acti
 
             if (hasContent && ReadContent)
             {
-                var formatter = SelectContentParser(contentType!);
-                responseModel.Content = await formatter.ParseAsync(response, cancellationToken);
+                var formatter = SelectContentParser(contentType);
+                responseModel.Content = await formatter.ReadAsync(response, cancellationToken);
             }
 
             var statusCode = (int) response.StatusCode;
@@ -139,21 +139,20 @@ protected override async ValueTask<IActivityExecutionResult> OnExecuteAsync(Acti
             return Outcomes(outcomes);
         }
 
-        private IHttpResponseBodyParser SelectContentParser(string contentType)
+        private IHttpResponseContentReader SelectContentParser(string? contentType)
         {
-            var simpleContentType = contentType?.Split(';').First();
+            var simpleContentType = contentType?.Split(';').First() ?? "";
             var formatters = _parsers.OrderByDescending(x => x.Priority).ToList();
-            return formatters.FirstOrDefault(
-                x => x.SupportedContentTypes.Contains(simpleContentType, StringComparer.OrdinalIgnoreCase)
-            ) ?? formatters.Last();
+
+            return formatters.FirstOrDefault(x => x.GetSupportsContentType(simpleContentType)) ?? formatters.Last();
         }
 
         private HttpRequestMessage CreateRequest()
         {
             var method = Method ?? HttpMethods.Get;
             var methodSupportsBody = GetMethodSupportsBody(method);
             var url = Url;
-            var request = new HttpRequestMessage(new HttpMethod(Method), url);
+            var request = new HttpRequestMessage(new HttpMethod(method), url);
             var authorizationHeaderValue = Authorization;
             var requestHeaders = new HeaderDictionary(RequestHeaders.ToDictionary(x => x.Key, x => new StringValues(x.Value.Split(','))));
 

src/activities/Elsa.Activities.Http/Activities/WriteHttpResponse/WriteHttpResponse.cs

@@ -1,10 +1,13 @@
+using System;
 using System.Net;
+using System.Threading;
 using System.Threading.Tasks;
 using Elsa.Activities.Http.Models;
 using Elsa.ActivityResults;
 using Elsa.Attributes;
 using Elsa.Design;
 using Elsa.Expressions;
+using Elsa.Serialization;
 using Elsa.Services;
 using Elsa.Services.Models;
 using Microsoft.AspNetCore.Http;
@@ -22,11 +25,13 @@ namespace Elsa.Activities.Http
     public class WriteHttpResponse : Activity
     {
         private readonly IHttpContextAccessor _httpContextAccessor;
+        private readonly IContentSerializer _contentSerializer;
 
-        public WriteHttpResponse(IHttpContextAccessor httpContextAccessor, IStringLocalizer<WriteHttpResponse> localizer)
+        public WriteHttpResponse(IHttpContextAccessor httpContextAccessor, IStringLocalizer<WriteHttpResponse> localizer, IContentSerializer contentSerializer)
         {
             T = localizer;
             _httpContextAccessor = httpContextAccessor;
+            _contentSerializer = contentSerializer;
         }
 
         private IStringLocalizer T { get; }
@@ -45,10 +50,10 @@ public WriteHttpResponse(IHttpContextAccessor httpContextAccessor, IStringLocali
         public HttpStatusCode StatusCode { get; set; } = HttpStatusCode.OK;
 
         /// <summary>
-        /// The content to send along with the response
+        /// The content to send along with the response.
         /// </summary>
         [ActivityInput(Hint = "The HTTP content to write.", UIHint = ActivityInputUIHints.MultiLine, SupportedSyntaxes = new[] { SyntaxNames.JavaScript, SyntaxNames.Liquid })]
-        public string? Content { get; set; }
+        public object? Content { get; set; }
 
         /// <summary>
         /// The Content-Type header to send along with the response.
@@ -68,7 +73,7 @@ public WriteHttpResponse(IHttpContextAccessor httpContextAccessor, IStringLocali
         [ActivityInput(
             Hint = "The character set to use when writing the response.",
             UIHint = ActivityInputUIHints.Dropdown,
-            Options = new[] { "utf-8", "ASCII", "ANSI", "ISO-8859-1" },
+            Options = new[] { "", "utf-8", "ASCII", "ANSI", "ISO-8859-1" },
             DefaultValue = "utf-8",
             SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid },
             Category = PropertyCategories.Advanced)]
@@ -78,10 +83,10 @@ public WriteHttpResponse(IHttpContextAccessor httpContextAccessor, IStringLocali
         /// The headers to send along with the response.
         /// </summary>
         [ActivityInput(
-            Hint = "Additional headers to write.", 
+            Hint = "Additional headers to write.",
             UIHint = ActivityInputUIHints.MultiLine,
             DefaultSyntax = SyntaxNames.Json,
-            SupportedSyntaxes = new[]{ SyntaxNames.JavaScript, SyntaxNames.Liquid, SyntaxNames.Json },
+            SupportedSyntaxes = new[] { SyntaxNames.JavaScript, SyntaxNames.Liquid, SyntaxNames.Json },
             Category = PropertyCategories.Advanced
         )]
         public HttpResponseHeaders? ResponseHeaders { get; set; }
@@ -95,7 +100,7 @@ protected override async ValueTask<IActivityExecutionResult> OnExecuteAsync(Acti
                 return Fault(T["Response has already started"]!);
 
             response.StatusCode = (int) StatusCode;
-            response.ContentType = $"{ContentType};charset={CharSet}";
+            response.ContentType = string.IsNullOrWhiteSpace(CharSet) ? ContentType : $"{ContentType};charset={CharSet}";
 
             var headers = ResponseHeaders;
 
@@ -105,12 +110,37 @@ protected override async ValueTask<IActivityExecutionResult> OnExecuteAsync(Acti
                     response.Headers[header.Key] = header.Value;
             }
 
-            var bodyText = Content;
-
-            if (!string.IsNullOrWhiteSpace(bodyText))
-                await response.WriteAsync(bodyText, context.CancellationToken);
+            await WriteContentAsync(context.CancellationToken);
 
             return Done();
         }
+
+        private async Task WriteContentAsync(CancellationToken cancellationToken)
+        {
+            var httpContext = _httpContextAccessor.HttpContext ?? new DefaultHttpContext();
+            var response = httpContext.Response;
+
+            var content = Content;
+
+            if (content == null)
+                return;
+
+            if (content is string stringContent)
+            {
+                if (!string.IsNullOrWhiteSpace(stringContent))
+                    await response.WriteAsync(stringContent, cancellationToken);
+
+                return;
+            }
+
+            if (content is byte[] buffer)
+            {
+                await response.Body.WriteAsync(buffer, cancellationToken);
+                return;
+            }
+
+            var json = _contentSerializer.Serialize(content);
+            await response.WriteAsync(json, cancellationToken);
+        }
     }
 }

src/activities/Elsa.Activities.Http/Extensions/ServiceCollectionExtensions.cs

@@ -6,6 +6,8 @@
 using Elsa.Activities.Http.Liquid;
 using Elsa.Activities.Http.Options;
 using Elsa.Activities.Http.Parsers;
+using Elsa.Activities.Http.Parsers.Request;
+using Elsa.Activities.Http.Parsers.Response;
 using Elsa.Activities.Http.Services;
 using Elsa.Scripting.Liquid.Extensions;
 using Microsoft.AspNetCore.Http;
@@ -36,8 +38,9 @@ public static IServiceCollection AddHttpServices(this IServiceCollection service
                 .AddSingleton<IHttpRequestBodyParser, DefaultHttpRequestBodyParser>()
                 .AddSingleton<IHttpRequestBodyParser, JsonHttpRequestBodyParser>()
                 .AddSingleton<IHttpRequestBodyParser, FormHttpRequestBodyParser>()
-                .AddSingleton<IHttpResponseBodyParser, DefaultHttpResponseBodyParser>()
-                .AddSingleton<IHttpResponseBodyParser, JsonHttpResponseBodyParser>()
+                .AddSingleton<IHttpResponseContentReader, DefaultHttpResponseContentReader>()
+                .AddSingleton<IHttpResponseContentReader, JsonHttpResponseContentReader>()
+                .AddSingleton<IHttpResponseContentReader, FileResponseContentReader>()
                 .AddSingleton<IActionContextAccessor, ActionContextAccessor>()
                 .AddSingleton<IAbsoluteUrlProvider, DefaultAbsoluteUrlProvider>()
                 .AddBookmarkProvider<HttpEndpointBookmarkProvider>()

src/activities/Elsa.Activities.Http/Middleware/HttpEndpointMiddleware.cs

@@ -7,6 +7,7 @@
 using Elsa.Activities.Http.Extensions;
 using Elsa.Activities.Http.Models;
 using Elsa.Activities.Http.Parsers;
+using Elsa.Activities.Http.Parsers.Request;
 using Elsa.Activities.Http.Services;
 using Elsa.Persistence;
 using Elsa.Persistence.Specifications.WorkflowInstances;

src/activities/Elsa.Activities.Http/Parsers/DefaultHttpRequestBodyParser.cs → src/activities/Elsa.Activities.Http/Parsers/Request/DefaultHttpRequestBodyParser.cs

@@ -5,7 +5,7 @@
 using Elsa.Activities.Http.Services;
 using Microsoft.AspNetCore.Http;
 
-namespace Elsa.Activities.Http.Parsers
+namespace Elsa.Activities.Http.Parsers.Request
 {
     public class DefaultHttpRequestBodyParser : IHttpRequestBodyParser
     {

src/activities/Elsa.Activities.Http/Parsers/Response/DefaultHttpResponseContentReader.cs

@@ -0,0 +1,14 @@
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using Elsa.Activities.Http.Services;
+
+namespace Elsa.Activities.Http.Parsers.Response
+{
+    public class DefaultHttpResponseContentReader : IHttpResponseContentReader
+    {
+        public int Priority => -1;
+        public bool GetSupportsContentType(string contentType) => true;
+        public async Task<object> ReadAsync(HttpResponseMessage response, CancellationToken cancellationToken) => await response.Content.ReadAsStringAsync();
+    }
+}

src/activities/Elsa.Activities.Http/Parsers/Response/FileResponseContentReader.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Linq;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using Elsa.Activities.Http.Services;
+
+namespace Elsa.Activities.Http.Parsers.Response
+{
+    public class FileResponseContentReader : IHttpResponseContentReader
+    {
+        public virtual int Priority => 5;
+        public virtual bool GetSupportsContentType(string contentType)
+        {
+            var types = new[] { "audio", "video", "application", "pdf" };
+            return types.Any(x => contentType.Contains(x, StringComparison.OrdinalIgnoreCase));
+        }
+
+        public async Task<object> ReadAsync(HttpResponseMessage response, CancellationToken cancellationToken) => await response.Content.ReadAsByteArrayAsync();
+    }
+}

src/activities/Elsa.Activities.Http/Parsers/JsonHttpResponseBodyParser.cs → src/activities/Elsa.Activities.Http/Parsers/Response/JsonHttpResponseContentReader.cs

@@ -1,19 +1,19 @@
-using System.Collections.Generic;
+using System;
 using System.Dynamic;
 using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
 using Elsa.Activities.Http.Services;
 using Newtonsoft.Json;
 
-namespace Elsa.Activities.Http.Parsers
+namespace Elsa.Activities.Http.Parsers.Response
 {
-    public class JsonHttpResponseBodyParser : IHttpResponseBodyParser
+    public class JsonHttpResponseContentReader : IHttpResponseContentReader
     {
-        public int Priority => 0;
-        public IEnumerable<string?> SupportedContentTypes => new[] { "application/json", "text/json" };
+        public int Priority => 10;
+        public bool GetSupportsContentType(string contentType) => contentType.Contains("/json", StringComparison.OrdinalIgnoreCase);
 
-        public async Task<object> ParseAsync(HttpResponseMessage response, CancellationToken cancellationToken)
+        public async Task<object> ReadAsync(HttpResponseMessage response, CancellationToken cancellationToken)
         {
 #if NET
             var json = (await response.Content.ReadAsStringAsync(cancellationToken)).Trim();

src/activities/Elsa.Activities.Http/Services/IHttpResponseContentReader.cs

@@ -0,0 +1,13 @@
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Elsa.Activities.Http.Services
+{
+    public interface IHttpResponseContentReader
+    {
+        int Priority { get; }
+        bool GetSupportsContentType(string contentType);
+        Task<object> ReadAsync(HttpResponseMessage response, CancellationToken cancellationToken);
+    }
+}

src/scripting/Elsa.Scripting.JavaScript/Converters/Jint/ByteArrayConverter.cs

@@ -0,0 +1,24 @@
+using Jint;
+using Jint.Native;
+using Jint.Runtime.Interop;
+
+namespace Elsa.Scripting.JavaScript.Converters.Jint
+{
+    /// <summary>
+    /// Prevents Jint from returning byte[] as object[].
+    /// </summary>
+    internal class ByteArrayConverter : IObjectConverter
+    {
+        public bool TryConvert(Engine engine, object value, out JsValue result)
+        {
+            result = JsValue.Null;
+
+            if (value is not byte[] buffer)
+                return false;
+
+            result = new ObjectWrapper(engine, buffer);
+
+            return true;
+        }
+    }
+}

src/scripting/Elsa.Scripting.JavaScript/Converters/TruncatingNumberJsonConverter.cs → src/scripting/Elsa.Scripting.JavaScript/Converters/Json/TruncatingNumberJsonConverter.cs

@@ -1,7 +1,7 @@
 using System;
 using Newtonsoft.Json;
 
-namespace Elsa.Scripting.JavaScript.Converters
+namespace Elsa.Scripting.JavaScript.Converters.Json
 {
     /// <summary>
     /// Ensures that whole numeric values are serialized without any decimal (e.g. 2 instead of 2.0) to ensure deserialization to models having int properties works.