@Schema annotation with type String and allowableValues set doesn't generate enum drop-down in swagger-ui after upgrading from 1.6.6 (when Spring custom converter is used). Fixes #1663.

Author: bnasslahsen

springdoc-openapi-common/src/main/java/org/springdoc/core/GenericParameterService.java

@@ -331,7 +331,7 @@ Schema calculateSchema(Components components, ParameterInfo parameterInfo, Reque
 			Type type = ReturnTypeParser.getType(methodParameter);
 			if(type instanceof Class && optionalWebConversionServiceProvider.isPresent()){
 				WebConversionServiceProvider webConversionServiceProvider = optionalWebConversionServiceProvider.get();
-				if (!MethodParameterPojoExtractor.isSwaggerPrimitiveType((Class) type))
+				if (!MethodParameterPojoExtractor.isSwaggerPrimitiveType((Class) type) && methodParameter.getParameterType().getAnnotation(io.swagger.v3.oas.annotations.media.Schema.class)==null)
 					type = webConversionServiceProvider.getSpringConvertedType(methodParameter.getParameterType());
 			}
 			schemaN = SpringDocAnnotationsUtils.extractSchema(components, type, jsonView, methodParameter.getParameterAnnotations());

springdoc-openapi-webmvc-core/src/test/java/test/org/springdoc/api/v30/app188/FooBar.java

@@ -0,0 +1,36 @@
+/*
+ *
+ *  *
+ *  *  *
+ *  *  *  * Copyright 2019-2022 the original author or authors.
+ *  *  *  *
+ *  *  *  * Licensed under the Apache License, Version 2.0 (the "License");
+ *  *  *  * you may not use this file except in compliance with the License.
+ *  *  *  * You may obtain a copy of the License at
+ *  *  *  *
+ *  *  *  *      https://www.apache.org/licenses/LICENSE-2.0
+ *  *  *  *
+ *  *  *  * Unless required by applicable law or agreed to in writing, software
+ *  *  *  * distributed under the License is distributed on an "AS IS" BASIS,
+ *  *  *  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  *  *  * See the License for the specific language governing permissions and
+ *  *  *  * limitations under the License.
+ *  *  *
+ *  *
+ *
+ */
+
+package test.org.springdoc.api.v30.app188;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+
+@Schema(type = "String", allowableValues = { "foo", "bar" })
+public enum FooBar {
+    FOO,
+    BAR;
+
+    public String toLowerCase() {
+        String lower = this.name().toLowerCase();
+        return lower.replace("_", "-");
+    }
+}

springdoc-openapi-webmvc-core/src/test/java/test/org/springdoc/api/v30/app188/FooBarConverter.java

@@ -0,0 +1,40 @@
+/*
+ *
+ *  *
+ *  *  *
+ *  *  *  * Copyright 2019-2022 the original author or authors.
+ *  *  *  *
+ *  *  *  * Licensed under the Apache License, Version 2.0 (the "License");
+ *  *  *  * you may not use this file except in compliance with the License.
+ *  *  *  * You may obtain a copy of the License at
+ *  *  *  *
+ *  *  *  *      https://www.apache.org/licenses/LICENSE-2.0
+ *  *  *  *
+ *  *  *  * Unless required by applicable law or agreed to in writing, software
+ *  *  *  * distributed under the License is distributed on an "AS IS" BASIS,
+ *  *  *  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  *  *  * See the License for the specific language governing permissions and
+ *  *  *  * limitations under the License.
+ *  *  *
+ *  *
+ *
+ */
+
+package test.org.springdoc.api.v30.app188;
+
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.stereotype.Component;
+
+@Component
+public class FooBarConverter implements Converter<String, FooBar> {
+
+  @Override
+  public FooBar convert(String source) {
+    return FooBar.valueOf(fooBarToUpperCase(source));
+  }
+
+  private String fooBarToUpperCase(String source) {
+	  String upper = source.toUpperCase();
+    return upper.replace("-", "_");
+  }
+}

springdoc-openapi-webmvc-core/src/test/java/test/org/springdoc/api/v30/app188/HelloController.java

@@ -38,6 +38,7 @@
 import org.springframework.context.annotation.Bean;
 import org.springframework.http.MediaType;
 import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.method.HandlerMethod;
 
@@ -47,6 +48,11 @@ public class HelloController {
 	@GetMapping("/test")
 	public void test(){}
 
+	@GetMapping(value = "/example/{fooBar}")
+	public String getFooBar(@PathVariable FooBar fooBar) {
+		return fooBar.name();
+	}
+
 	@Bean
 	public OpenAPI openAPI(){return new OpenAPI().components(new Components());}
 

springdoc-openapi-webmvc-core/src/test/resources/results/3.0.1/app188.json

@@ -32,6 +32,49 @@
           }
         }
       }
+    },
+    "/example/{fooBar}": {
+      "get": {
+        "tags": [
+          "hello-controller"
+        ],
+        "operationId": "getFooBar",
+        "parameters": [
+          {
+            "name": "fooBar",
+            "in": "path",
+            "required": true,
+            "schema": {
+              "type": "string",
+              "enum": [
+                "foo",
+                "bar"
+              ]
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "OK",
+            "content": {
+              "*/*": {
+                "schema": {
+                  "type": "string"
+                }
+              }
+            }
+          },
+          "5xx": {
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ErrorResponse"
+                }
+              }
+            }
+          }
+        }
+      }
     }
   },
   "components": {