Add unhandledException to 'spring' generator, which declares all operation methods to throw a generic exception, allowing implementations to unhandle checked exceptions. This is useful whenever it is unnecessary to handle specific exceptions and, more importantly, allow generic constructs (eg. Spring @ControllerAdvice) to tackle unhandled exceptions from a single point (for instance, tackle all unhandled exceptions as an HTTP500 while excluding the stacktrace in the response body). (#2482)

Author: mcac0006

docs/generators/spring.md

@@ -61,4 +61,5 @@ sidebar_label: spring
 |useOptional|Use Optional container for optional parameters| |false|
 |hateoas|Use Spring HATEOAS library to allow adding HATEOAS links| |false|
 |returnSuccessCode|Generated server returns 2xx code| |false|
+|unhandledException|Declare operation methods to throw a generic exception and allow unhandled exceptions (useful for Spring `@ControllerAdvice` directives).|false|
 |library|library template (sub-template)|<dl><dt>**spring-boot**</dt><dd>Spring-boot Server application using the SpringFox integration.</dd><dt>**spring-mvc**</dt><dd>Spring-MVC Server application using the SpringFox integration.</dd><dt>**spring-cloud**</dt><dd>Spring-Cloud-Feign client with Spring-Boot auto-configured settings.</dd><dl>|spring-boot|

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SpringCodegen.java

@@ -66,6 +66,7 @@ public class SpringCodegen extends AbstractJavaCodegen
     public static final String API_FIRST = "apiFirst";
     public static final String HATEOAS = "hateoas";
     public static final String RETURN_SUCCESS_CODE = "returnSuccessCode";
+    public static final String UNHANDLED_EXCEPTION_HANDLING = "unhandledException";
 
     protected String title = "OpenAPI Spring";
     protected String configPackage = "org.openapitools.configuration";
@@ -88,6 +89,7 @@ public class SpringCodegen extends AbstractJavaCodegen
     protected boolean virtualService = false;
     protected boolean hateoas = false;
     protected boolean returnSuccessCode = false;
+    protected boolean unhandledException = false;
 
     public SpringCodegen() {
         super();
@@ -130,6 +132,7 @@ public SpringCodegen() {
         cliOptions.add(CliOption.newBoolean(USE_OPTIONAL,"Use Optional container for optional parameters", useOptional));
         cliOptions.add(CliOption.newBoolean(HATEOAS, "Use Spring HATEOAS library to allow adding HATEOAS links", hateoas));
         cliOptions.add(CliOption.newBoolean(RETURN_SUCCESS_CODE, "Generated server returns 2xx code", returnSuccessCode));
+        cliOptions.add(CliOption.newBoolean(UNHANDLED_EXCEPTION_HANDLING, "Declare operation methods to throw a generic exception and allow unhandled exceptions (useful for Spring `@ControllerAdvice` directives).", unhandledException));
 
         supportedLibraries.put(SPRING_BOOT, "Spring-boot Server application using the SpringFox integration.");
         supportedLibraries.put(SPRING_MVC_LIBRARY, "Spring-MVC Server application using the SpringFox integration.");
@@ -286,6 +289,12 @@ public void processOpts() {
             this.setReturnSuccessCode(Boolean.valueOf(additionalProperties.get(RETURN_SUCCESS_CODE).toString()));
         }
 
+        if (additionalProperties.containsKey(UNHANDLED_EXCEPTION_HANDLING)) {
+            this.setUnhandledException(Boolean.valueOf(additionalProperties.get(UNHANDLED_EXCEPTION_HANDLING).toString()));
+        } else {
+            additionalProperties.put(UNHANDLED_EXCEPTION_HANDLING, this.isUnhandledException());
+        }
+
         typeMapping.put("file", "Resource");
         importMapping.put("Resource", "org.springframework.core.io.Resource");
 
@@ -687,6 +696,10 @@ public String getConfigPackage() {
         return this.configPackage;
     }
 
+    public boolean isUnhandledException() {
+        return unhandledException;
+    }
+
     public void setBasePackage(String basePackage) {
         this.basePackage = basePackage;
     }
@@ -737,6 +750,10 @@ public void setReturnSuccessCode(boolean returnSuccessCode) {
         this.returnSuccessCode = returnSuccessCode;
     }
 
+    public void setUnhandledException(boolean unhandledException) {
+        this.unhandledException = unhandledException;
+    }
+
     @Override
     public void postProcessModelProperty(CodegenModel model, CodegenProperty property) {
         super.postProcessModelProperty(model, property);

modules/openapi-generator/src/main/resources/JavaSpring/api.mustache

@@ -109,7 +109,7 @@ public interface {{classname}} {
         produces = { {{#produces}}"{{{mediaType}}}"{{#hasMore}}, {{/hasMore}}{{/produces}} }, {{/hasProduces}}{{#hasConsumes}}
         consumes = { {{#consumes}}"{{{mediaType}}}"{{#hasMore}}, {{/hasMore}}{{/consumes}} },{{/hasConsumes}}{{/singleContentTypes}}
         method = RequestMethod.{{httpMethod}})
-    {{#jdk8}}default {{/jdk8}}{{#responseWrapper}}{{.}}<{{/responseWrapper}}ResponseEntity<{{>returnTypes}}>{{#responseWrapper}}>{{/responseWrapper}} {{#delegate-method}}_{{/delegate-method}}{{operationId}}({{#allParams}}{{>queryParams}}{{>pathParams}}{{>headerParams}}{{>bodyParams}}{{>formParams}}{{#hasMore}},{{/hasMore}}{{^hasMore}}{{#reactive}}, {{/reactive}}{{/hasMore}}{{/allParams}}{{#reactive}}ServerWebExchange exchange{{/reactive}}){{^jdk8}};{{/jdk8}}{{#jdk8}} {
+    {{#jdk8}}default {{/jdk8}}{{#responseWrapper}}{{.}}<{{/responseWrapper}}ResponseEntity<{{>returnTypes}}>{{#responseWrapper}}>{{/responseWrapper}} {{#delegate-method}}_{{/delegate-method}}{{operationId}}({{#allParams}}{{>queryParams}}{{>pathParams}}{{>headerParams}}{{>bodyParams}}{{>formParams}}{{#hasMore}},{{/hasMore}}{{^hasMore}}{{#reactive}}, {{/reactive}}{{/hasMore}}{{/allParams}}{{#reactive}}ServerWebExchange exchange{{/reactive}}){{^jdk8}};{{/jdk8}}{{#jdk8}}{{#unhandledException}} throws Exception{{/unhandledException}} {
         {{#delegate-method}}
         return {{operationId}}({{#allParams}}{{paramName}}{{#hasMore}}, {{/hasMore}}{{/allParams}}{{#reactive}}{{#hasParams}}, {{/hasParams}}exchange{{/reactive}});
     }

modules/openapi-generator/src/test/java/org/openapitools/codegen/java/spring/SpringCodegenTest.java

@@ -67,6 +67,7 @@ public void testInitialConfigValues() throws Exception {
         Assert.assertEquals(codegen.getConfigPackage(), "org.openapitools.configuration");
         Assert.assertEquals(codegen.additionalProperties().get(SpringCodegen.CONFIG_PACKAGE), "org.openapitools.configuration");
         Assert.assertEquals(codegen.additionalProperties().get(SpringCodegen.SERVER_PORT), "8082");
+        Assert.assertEquals(codegen.additionalProperties().get(SpringCodegen.UNHANDLED_EXCEPTION_HANDLING), false);
     }
 
     @Test
@@ -78,6 +79,7 @@ public void testSettersForConfigValues() throws Exception {
         codegen.setInvokerPackage("xx.yyyyyyyy.invoker");
         codegen.setBasePackage("xx.yyyyyyyy.base");
         codegen.setConfigPackage("xx.yyyyyyyy.config");
+        codegen.setUnhandledException(true);
         codegen.processOpts();
 
         Assert.assertEquals(codegen.additionalProperties().get(CodegenConstants.HIDE_GENERATION_TIMESTAMP), Boolean.TRUE);
@@ -92,6 +94,8 @@ public void testSettersForConfigValues() throws Exception {
         Assert.assertEquals(codegen.additionalProperties().get(SpringCodegen.BASE_PACKAGE), "xx.yyyyyyyy.base");
         Assert.assertEquals(codegen.getConfigPackage(), "xx.yyyyyyyy.config");
         Assert.assertEquals(codegen.additionalProperties().get(SpringCodegen.CONFIG_PACKAGE), "xx.yyyyyyyy.config");
+        Assert.assertEquals(codegen.isUnhandledException(), true);
+        Assert.assertEquals(codegen.additionalProperties().get(SpringCodegen.UNHANDLED_EXCEPTION_HANDLING), true);
     }
 
     @Test