#324 - fix double registration of model converters when grouped api is used

Author: m-kay

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

@@ -1,7 +1,5 @@
 package org.springdoc.core;
 
-import io.swagger.v3.core.converter.ModelConverter;
-import io.swagger.v3.core.converter.ModelConverters;
 import io.swagger.v3.core.util.AnnotationsUtils;
 import io.swagger.v3.core.util.ReflectionUtils;
 import io.swagger.v3.oas.annotations.Hidden;
@@ -17,6 +15,7 @@
 import org.apache.commons.lang3.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.springdoc.core.converters.ModelConverterRegistrar;
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.boot.autoconfigure.AutoConfigurationPackages;
 import org.springframework.context.ApplicationContext;
@@ -45,7 +44,7 @@ public class OpenAPIBuilder {
     private String serverBaseUrl;
 
     @SuppressWarnings("WeakerAccess")
-    OpenAPIBuilder(Optional<OpenAPI> openAPI, ApplicationContext context, SecurityParser securityParser, List<ModelConverter> modelConverters) {
+    OpenAPIBuilder(Optional<OpenAPI> openAPI, ApplicationContext context, SecurityParser securityParser) {
         if (openAPI.isPresent()) {
             this.openAPI = openAPI.get();
             if (this.openAPI.getComponents() == null)
@@ -59,7 +58,6 @@ public class OpenAPIBuilder {
         }
         this.context = context;
         this.securityParser = securityParser;
-        modelConverters.forEach(ModelConverters.getInstance()::addConverter);
     }
 
     private static String splitCamelCase(String str) {

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

@@ -2,6 +2,7 @@
 
 import io.swagger.v3.core.converter.ModelConverter;
 import io.swagger.v3.oas.models.OpenAPI;
+import org.springdoc.core.converters.ModelConverterRegistrar;
 import org.springdoc.core.converters.ObjectNodeConverter;
 import org.springdoc.core.converters.PropertyCustomizingConverter;
 import org.springdoc.core.customizers.PropertyCustomizer;
@@ -13,6 +14,7 @@
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
 
+import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
 
@@ -43,8 +45,13 @@ IgnoredParameterAnnotationsDefault ignoredParameterAnnotationsDefault() {
     }
 
     @Bean
-    public OpenAPIBuilder openAPIBuilder(Optional<OpenAPI> openAPI, ApplicationContext context, SecurityParser securityParser, List<ModelConverter> modelConverters) {
-        return new OpenAPIBuilder(openAPI, context, securityParser, modelConverters);
+    public OpenAPIBuilder openAPIBuilder(Optional<OpenAPI> openAPI, ApplicationContext context, SecurityParser securityParser) {
+        return new OpenAPIBuilder(openAPI, context, securityParser);
+    }
+
+    @Bean
+    public ModelConverterRegistrar modelConverterRegistrar(Optional<List<ModelConverter>> modelConverters) {
+        return new ModelConverterRegistrar(modelConverters.orElse(Collections.emptyList()));
     }
 
     @Bean

springdoc-openapi-common/src/main/java/org/springdoc/core/converters/ModelConverterRegistrar.java

@@ -0,0 +1,20 @@
+package org.springdoc.core.converters;
+
+import io.swagger.v3.core.converter.ModelConverter;
+import io.swagger.v3.core.converter.ModelConverters;
+
+import java.util.List;
+
+/**
+ * Wrapper for model converters to only register converters once
+ */
+public class ModelConverterRegistrar {
+
+    /**
+     * @param modelConverters spring registered model converter beans which have to be
+     *                        registered in {@link ModelConverters} instance
+     */
+    public ModelConverterRegistrar(List<ModelConverter> modelConverters) {
+        modelConverters.forEach(ModelConverters.getInstance()::addConverter);
+    }
+}