Use endpoint-specific JSON serialization settings, also fixing that enum values were converted to numbers instead of strings

src/server/Elsa.Server.Api/Endpoints/Activities/List.cs

@@ -3,6 +3,7 @@ using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Elsa.Metadata;
+using Elsa.Server.Api.Services;
 using Elsa.Services;
 using Elsa.Services.Models;
 using Microsoft.AspNetCore.Http;
@@ -18,10 +19,12 @@ namespace Elsa.Server.Api.Endpoints.Activities
     public class List : Controller
     {
         private readonly IActivityTypeService _activityTypeService;
+        private readonly IEndpointContentSerializerSettingsProvider _serializerSettingsProvider;
 
-        public List(IActivityTypeService activityTypeService)
+        public List(IActivityTypeService activityTypeService, IEndpointContentSerializerSettingsProvider serializerSettingsProvider)
         {
             _activityTypeService = activityTypeService;
+            _serializerSettingsProvider = serializerSettingsProvider;
         }
 
         [HttpGet]
@@ -37,7 +40,7 @@ namespace Elsa.Server.Api.Endpoints.Activities
             var activityTypes = await _activityTypeService.GetActivityTypesAsync(cancellationToken);
             var tasks = activityTypes.Where(x => x.IsBrowsable).Select(x => DescribeActivity(x, cancellationToken)).ToList();
             var descriptors = await Task.WhenAll(tasks);
-            return Json(descriptors);
+            return Json(descriptors, _serializerSettingsProvider.GetSettings());
         }
 
         private async Task<ActivityDescriptor> DescribeActivity(ActivityType activityType, CancellationToken cancellationToken) => await _activityTypeService.DescribeActivityType(activityType, cancellationToken);

src/server/Elsa.Server.Api/Endpoints/WebhookDefinitions/Get.cs

@@ -6,6 +6,7 @@ using Elsa.Activities.Webhooks.Persistence;
 using Elsa.Models;
 using Elsa.Persistence.Specifications;
 using Elsa.Serialization;
+using Elsa.Server.Api.Services;
 using Elsa.Server.Api.Swagger.Examples;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
@@ -21,12 +22,12 @@ namespace Elsa.Server.Api.Endpoints.WebhookDefinitions
     public class Get : Controller
     {
         private readonly IWebhookDefinitionStore _webhookDefinitionStore;
-        private readonly IContentSerializer _serializer;
+        private readonly IEndpointContentSerializerSettingsProvider _serializerSettingsProvider;
 
-        public Get(IWebhookDefinitionStore webhookDefinitionStore, IContentSerializer serializer)
+        public Get(IWebhookDefinitionStore webhookDefinitionStore, IEndpointContentSerializerSettingsProvider serializerSettingsProvider)
         {
             _webhookDefinitionStore = webhookDefinitionStore;
-            _serializer = serializer;
+            _serializerSettingsProvider = serializerSettingsProvider;
         }
 
         [HttpGet]
@@ -42,7 +43,7 @@ namespace Elsa.Server.Api.Endpoints.WebhookDefinitions
         public async Task<IActionResult> Handle(string webhookDefinitionId, CancellationToken cancellationToken = default)
         {
             var webhookDefinition = await _webhookDefinitionStore.FindAsync(new EntityIdSpecification<WebhookDefinition>(webhookDefinitionId), cancellationToken);
-            return webhookDefinition == null ? (IActionResult) NotFound() : Json(webhookDefinition, _serializer.GetSettings());
+            return webhookDefinition == null ? (IActionResult) NotFound() : Json(webhookDefinition, _serializerSettingsProvider.GetSettings());
         }
     }
 }

src/server/Elsa.Server.Api/Endpoints/WebhookDefinitions/List.cs

@@ -8,6 +8,7 @@ using Elsa.Models;
 using Elsa.Persistence.Specifications;
 using Elsa.Serialization;
 using Elsa.Server.Api.Models;
+using Elsa.Server.Api.Services;
 using Elsa.Server.Api.Swagger.Examples;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
@@ -23,12 +24,12 @@ namespace Elsa.Server.Api.Endpoints.WebhookDefinitions
     public class List : Controller
     {
         private readonly IWebhookDefinitionStore _webhookDefinitionStore;
-        private readonly IContentSerializer _serializer;
+        private readonly IEndpointContentSerializerSettingsProvider _serializerSettingsProvider;
 
-        public List(IWebhookDefinitionStore webhookDefinitionStore, IContentSerializer serializer)
+        public List(IWebhookDefinitionStore webhookDefinitionStore, IEndpointContentSerializerSettingsProvider serializerSettingsProvider)
         {
             _webhookDefinitionStore = webhookDefinitionStore;
-            _serializer = serializer;
+            _serializerSettingsProvider = serializerSettingsProvider;
         }
 
         [HttpGet]
@@ -45,7 +46,7 @@ namespace Elsa.Server.Api.Endpoints.WebhookDefinitions
             var specification = Specification<WebhookDefinition>.Identity;
             var items = await _webhookDefinitionStore.FindManyAsync(specification, cancellationToken: cancellationToken);
 
-            return Json(items, _serializer.GetSettings());
+            return Json(items, _serializerSettingsProvider.GetSettings());
         }
     }
 }

src/server/Elsa.Server.Api/Extensions/ServiceCollectionExtensions.cs

@@ -19,7 +19,6 @@ namespace Microsoft.Extensions.DependencyInjection
         {
             setupNewtonsoftJson ??= _ => { }; 
             services.AddControllers().AddNewtonsoftJson(setupNewtonsoftJson);
-                
             services.AddRouting(options => options.LowercaseUrls = true);
 
             services.AddVersionedApiExplorer(o =>
@@ -39,6 +38,7 @@ namespace Microsoft.Extensions.DependencyInjection
             services.AddSingleton<ConnectionConverter>();
             services.AddSingleton<ActivityBlueprintConverter>();
             services.AddSingleton<IWorkflowBlueprintMapper, WorkflowBlueprintMapper>();
+            services.AddSingleton<IEndpointContentSerializerSettingsProvider, EndpointContentSerializerSettingsProvider>();
             services.AddAutoMapperProfile<AutoMapperProfile>();
             return services;
         }

src/server/Elsa.Server.Api/Services/EndpointContentSerializerSettingsProvider.cs

@@ -0,0 +1,33 @@
+using Elsa.Serialization.Converters;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Serialization;
+using NodaTime;
+using NodaTime.Serialization.JsonNet;
+
+namespace Elsa.Server.Api.Services
+{
+    public class EndpointContentSerializerSettingsProvider : IEndpointContentSerializerSettingsProvider
+    {
+        private readonly JsonSerializerSettings _serializerSettings;
+        
+        public EndpointContentSerializerSettingsProvider()
+        {
+            _serializerSettings = new JsonSerializerSettings();
+            _serializerSettings.ConfigureForNodaTime(DateTimeZoneProviders.Tzdb);
+            _serializerSettings.NullValueHandling = NullValueHandling.Ignore;
+            _serializerSettings.TypeNameAssemblyFormatHandling = TypeNameAssemblyFormatHandling.Simple;
+            _serializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver
+            {
+                NamingStrategy = new CamelCaseNamingStrategy
+                {
+                    ProcessDictionaryKeys = false,
+                    ProcessExtensionDataNames = true,
+                    OverrideSpecifiedNames = false
+                }
+            };
+            _serializerSettings.Converters.Add(new FlagEnumConverter(new DefaultNamingStrategy()));
+        }
+
+        public JsonSerializerSettings GetSettings() => _serializerSettings;
+    }
+}

src/server/Elsa.Server.Api/Services/IEndpointContentSerializerSettingsProvider.cs

@@ -0,0 +1,9 @@
+using Newtonsoft.Json;
+
+namespace Elsa.Server.Api.Services
+{
+    public interface IEndpointContentSerializerSettingsProvider
+    {
+        JsonSerializerSettings GetSettings();
+    }
+}