Use ContentTypes for dataType and Accept in jQuery proxy generator

Refs abpframework/abp#23732

framework/src/Volo.Abp.Http/Volo/Abp/Http/ProxyScripting/Generators/JQuery/JQueryProxyScriptGenerator.cs

@@ -136,9 +136,7 @@ public class JQueryProxyScriptGenerator : IProxyScriptGenerator, ITransientDepen
         AddAjaxCallParameters(script, action);
 
         var ajaxParamsIsFromForm = action.Parameters.Any(x => x.BindingSourceId == ParameterBindingSources.Form);
-        var dataType = action.ReturnValue.Type == ReturnValueApiDescriptionModel.Create(typeof(string)).Type
+        var dataType = GetJQueryDataTypeAndAcceptOverride(action);
-            ? "{ dataType: 'text' }, "
-            : string.Empty;
         script.AppendLine(ajaxParamsIsFromForm
             ? "      }, $.extend(true, {}, " + dataType + "{ contentType: 'application/x-www-form-urlencoded; charset=UTF-8' }, ajaxParams)));"
             : "      }, " + dataType + "ajaxParams));");
@@ -146,6 +144,46 @@ public class JQueryProxyScriptGenerator : IProxyScriptGenerator, ITransientDepen
         script.AppendLine("    };");
     }
 
+    private static string GetJQueryDataTypeAndAcceptOverride(ActionApiDescriptionModel action)
+    {
+        var contentTypes = action.ReturnValue.ContentTypes;
+        var isStringReturn = action.ReturnValue.Type == ReturnValueApiDescriptionModel.Create(typeof(string)).Type;
+
+        if (contentTypes is { Count: > 0 })
+        {
+            var normalized = contentTypes.Select(NormalizeMediaType).ToList();
+
+            if (normalized.Any(IsJsonMediaType))
+            {
+                return "{ dataType: 'json', headers: { Accept: 'application/json' } }, ";
+            }
+
+            if (normalized.All(ct => ct.StartsWith("text/", StringComparison.OrdinalIgnoreCase)))
+            {
+                return "{ dataType: 'text', headers: { Accept: 'text/plain' } }, ";
+            }
+        }
+
+        return isStringReturn ? "{ dataType: 'text' }, " : string.Empty;
+    }
+
+    private static bool IsJsonMediaType(string normalizedMediaType)
+    {
+        return normalizedMediaType.Equals("application/json", StringComparison.OrdinalIgnoreCase) ||
+               normalizedMediaType.Equals("text/json", StringComparison.OrdinalIgnoreCase) ||
+               normalizedMediaType.EndsWith("+json", StringComparison.OrdinalIgnoreCase);
+    }
+
+    private static string NormalizeMediaType(string mediaType)
+    {
+        if (string.IsNullOrWhiteSpace(mediaType))
+        {
+            return string.Empty;
+        }
+        var semi = mediaType.IndexOf(';');
+        return (semi < 0 ? mediaType : mediaType.Substring(0, semi)).Trim();
+    }
+
     private static string FindBestApiVersion(ActionApiDescriptionModel action)
     {
         //var configuredVersion = GetConfiguredApiVersion(); //TODO: Implement

framework/test/Volo.Abp.Http.Tests/Volo/Abp/Http/ProxyScripting/Generators/JQuery/JQueryProxyScriptGenerator_ContentTypes_Tests.cs

@@ -0,0 +1,129 @@
+#nullable enable
+using System.Collections.Generic;
+using Microsoft.Extensions.Options;
+using Shouldly;
+using Volo.Abp.Http.Modeling;
+using Volo.Abp.Http.ProxyScripting.Generators;
+using Volo.Abp.Http.ProxyScripting.Generators.JQuery;
+using Xunit;
+
+namespace Volo.Abp.Http.ProxyScripting.Generators.JQuery;
+
+public class JQueryProxyScriptGenerator_ContentTypes_Tests
+{
+    private readonly JQueryProxyScriptGenerator _generator = new(
+        Microsoft.Extensions.Options.Options.Create(new DynamicJavaScriptProxyOptions()));
+
+    [Fact]
+    public void Should_Emit_Json_DataType_And_Accept_When_ContentTypes_Contain_Json()
+    {
+        var script = _generator.CreateScript(BuildAppModel(
+            returnType: "System.String",
+            contentTypes: new[] { "text/plain", "application/json", "text/json" }));
+
+        script.ShouldContain("dataType: 'json'");
+        script.ShouldContain("Accept: 'application/json'");
+        script.ShouldNotContain("dataType: 'text'");
+    }
+
+    [Fact]
+    public void Should_Emit_Text_DataType_And_Accept_When_ContentTypes_Only_Text()
+    {
+        var script = _generator.CreateScript(BuildAppModel(
+            returnType: "System.String",
+            contentTypes: new[] { "text/plain", "text/csv" }));
+
+        script.ShouldContain("dataType: 'text'");
+        script.ShouldContain("Accept: 'text/plain'");
+    }
+
+    [Fact]
+    public void Should_Fallback_To_Legacy_Text_When_Return_Is_String_And_ContentTypes_Null()
+    {
+        var script = _generator.CreateScript(BuildAppModel(
+            returnType: "System.String",
+            contentTypes: null));
+
+        // Legacy behavior preserved: string return → dataType: 'text' (no Accept override)
+        script.ShouldContain("dataType: 'text'");
+        script.ShouldNotContain("Accept:");
+    }
+
+    [Fact]
+    public void Should_Emit_No_DataType_For_Non_String_Return_Without_ContentTypes()
+    {
+        var script = _generator.CreateScript(BuildAppModel(
+            returnType: "System.Int32",
+            contentTypes: null));
+
+        script.ShouldNotContain("dataType: 'text'");
+        script.ShouldNotContain("dataType: 'json'");
+    }
+
+    [Fact]
+    public void Should_Not_Emit_Json_DataType_When_Only_Binary_ContentTypes()
+    {
+        var script = _generator.CreateScript(BuildAppModel(
+            returnType: "System.Byte[]",
+            contentTypes: new[] { "application/octet-stream", "image/png" }));
+
+        // jQuery dataType doesn't have a clean "blob" — fall through to no override
+        script.ShouldNotContain("dataType: 'json'");
+        script.ShouldNotContain("dataType: 'text'");
+    }
+
+    [Fact]
+    public void Should_Prefer_Json_When_Json_Present_Even_With_Other_Types()
+    {
+        var script = _generator.CreateScript(BuildAppModel(
+            returnType: "My.Project.UserDto",
+            contentTypes: new[] { "application/xml", "application/json", "text/html" }));
+
+        script.ShouldContain("dataType: 'json'");
+        script.ShouldContain("Accept: 'application/json'");
+    }
+
+    [Fact]
+    public void Case_Insensitive_Json_Detection()
+    {
+        var script = _generator.CreateScript(BuildAppModel(
+            returnType: "System.String",
+            contentTypes: new[] { "APPLICATION/JSON" }));
+
+        script.ShouldContain("dataType: 'json'");
+    }
+
+    private static ApplicationApiDescriptionModel BuildAppModel(string returnType, IList<string>? contentTypes)
+    {
+        var model = ApplicationApiDescriptionModel.Create();
+        var module = model.GetOrAddModule("app", "Default");
+        var controller = module.GetOrAddController(
+            name: "TestController",
+            groupName: null,
+            isRemoteService: true,
+            isIntegrationService: false,
+            apiVersion: null,
+            type: typeof(object));
+
+        var action = new ActionApiDescriptionModel
+        {
+            UniqueName = "DoSomethingAsync",
+            Name = "DoSomethingAsync",
+            HttpMethod = "GET",
+            Url = "api/test/do-something",
+            SupportedVersions = new List<string>(),
+            ParametersOnMethod = new List<MethodParameterApiDescriptionModel>(),
+            Parameters = new List<ParameterApiDescriptionModel>(),
+            ReturnValue = new ReturnValueApiDescriptionModel
+            {
+                Type = returnType,
+                TypeSimple = returnType,
+                ContentTypes = contentTypes,
+            },
+            AuthorizeDatas = new List<AuthorizeDataApiDescriptionModel>(),
+        };
+        controller.AddAction("DoSomethingAsync", action);
+
+        return model;
+    }
+}