Generate Enum-Dictionary-Keys (analogous to Newtonsoft) (#2825)

Generate Enum-Dictionary-Keys (analogous to Newtonsoft, since STJ does support it now).
domaindrivendev · Apr 24, 2024 · e97bc2a · e97bc2a
1 parent a920aeb
commit e97bc2a
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Showing 2 changed files with 26 additions and 1 deletion.
diff --git a/src/Swashbuckle.AspNetCore.SwaggerGen/SchemaGenerator/JsonSerializerDataContractResolver.cs b/src/Swashbuckle.AspNetCore.SwaggerGen/SchemaGenerator/JsonSerializerDataContractResolver.cs
@@ -57,10 +57,24 @@ public DataContract GetDataContractForType(Type type)
 
             if (IsSupportedDictionary(type, out Type keyType, out Type valueType))
             {
+                IEnumerable<string> keys = null;
+
+                if (keyType.IsEnum)
+                {
+                    // This is a special case where we know the possible key values
+                    var enumValuesAsJson = keyType.GetEnumValues()
+                        .Cast<object>()
+                        .Select(value => JsonConverterFunc(value));
+
+                    keys = enumValuesAsJson.Any(json => json.StartsWith("\""))
+                        ? enumValuesAsJson.Select(json => json.Replace("\"", string.Empty))
+                        : keyType.GetEnumNames();
+                }
+
                 return DataContract.ForDictionary(
                     underlyingType: type,
                     valueType: valueType,
-                    keys: null, // STJ doesn't currently support dictionaries with enum key types
+                    keys: keys,
                     jsonConverter: JsonConverterFunc);
             }
 

diff --git a/...shbuckle.AspNetCore.SwaggerGen.Test/SchemaGenerator/JsonSerializerSchemaGeneratorTests.cs b/...shbuckle.AspNetCore.SwaggerGen.Test/SchemaGenerator/JsonSerializerSchemaGeneratorTests.cs
@@ -781,6 +781,17 @@ public void GenerateSchema_HonorsSerializerOption_StringEnumConverter(
             Assert.Equal(expectedDefaultAsJson, propertySchema.Default.ToJson());
         }
 
+        [Fact]
+        public void GenerateSchema_HonorsEnumDictionaryKeys_StringEnumConverter()
+        {
+            var subject = Subject();
+            var schemaRepository = new SchemaRepository();
+
+            var referenceSchema = subject.GenerateSchema(typeof(Dictionary<IntEnum, string>), schemaRepository);
+
+            Assert.Equal(typeof(IntEnum).GetEnumNames(), referenceSchema.Properties.Keys);
+        }
+
         [Fact]
         public void GenerateSchema_HonorsSerializerAttribute_StringEnumConverter()
         {