[typescript-fetch] Add option to exclude RequestOpts from API interfaces (#23181)

* [typescript-fetch] Add withRequestOptsInInterface option to hide RequestOpts from API interfaces

The *RequestOpts methods are implementation details that build request
options before sending the fetch call. Most consumers using the API
interfaces don't need these methods exposed in the contract.

Add a new `withRequestOptsInInterface` boolean option (default: true
for backward compatibility) that controls whether *RequestOpts methods
appear in the generated API interface declarations. When set to false,
the methods remain as public methods on the class but are excluded from
the interface.

* Fix test: scope RequestOpts assertion to interface section

The previous test used indexOf("}") to find the interface end, which
matched the } inside @throws {RequiredError} JSDoc instead of the
actual closing brace. Use the class declaration position as the
boundary instead.

* Fix forbiddenapis violation: use explicit UTF-8 charset

Replace new String(byte[]) with new String(byte[], StandardCharsets.UTF_8)
to satisfy the forbiddenapis Maven plugin check.

* Add withRequestOptsInInterface to options test and regenerate docs

Author: guizmaii

docs/generators/typescript-fetch.md

@@ -47,6 +47,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 |useSquareBracketsInArrayNames|Setting this property to true will add brackets to array attribute names, e.g. my_values[].| |false|
 |validationAttributes|Setting this property to true will generate the validation attributes of model properties.| |false|
 |withInterfaces|Setting this property to true will generate interfaces next to the default class implementations.| |false|
+|withRequestOptsInInterface|Setting this property to true will include *RequestOpts methods in the API interface declarations. Set to false to keep them only on the class.| |true|
 |withoutRuntimeChecks|Setting this property to true will remove any runtime checks on the request and response payloads. Payloads will be casted to their expected types.| |false|
 
 ## IMPORT MAPPING

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

@@ -61,13 +61,15 @@ public class TypeScriptFetchClientCodegen extends AbstractTypeScriptClientCodege
     public static final String PASCAL_CASE = "PascalCase";
     public static final String USE_SQUARE_BRACKETS_IN_ARRAY_NAMES = "useSquareBracketsInArrayNames";
     public static final String VALIDATION_ATTRIBUTES = "validationAttributes";
+    public static final String WITH_REQUEST_OPTS_IN_INTERFACE = "withRequestOptsInInterface";
 
     @Getter @Setter
     protected String npmRepository = null;
     @Getter @Setter
     protected String importFileExtension = "";
     private boolean useSingleRequestParameter = true;
     private boolean prefixParameterInterfaces = false;
+    private boolean withRequestOptsInInterface = true;
     protected boolean addedApiIndex = false;
     protected boolean addedModelIndex = false;
     protected boolean withoutRuntimeChecks = false;
@@ -130,6 +132,7 @@ public TypeScriptFetchClientCodegen() {
         this.cliOptions.add(new CliOption(FILE_NAMING, "Naming convention for the output files: 'PascalCase', 'camelCase', 'kebab-case'.").defaultValue(this.fileNaming));
         this.cliOptions.add(new CliOption(USE_SQUARE_BRACKETS_IN_ARRAY_NAMES, "Setting this property to true will add brackets to array attribute names, e.g. my_values[].", SchemaTypeUtil.BOOLEAN_TYPE).defaultValue(Boolean.FALSE.toString()));
         this.cliOptions.add(new CliOption(VALIDATION_ATTRIBUTES, "Setting this property to true will generate the validation attributes of model properties.", SchemaTypeUtil.BOOLEAN_TYPE).defaultValue(Boolean.FALSE.toString()));
+        this.cliOptions.add(new CliOption(WITH_REQUEST_OPTS_IN_INTERFACE, "Setting this property to true will include *RequestOpts methods in the API interface declarations. Set to false to keep them only on the class.", SchemaTypeUtil.BOOLEAN_TYPE).defaultValue(Boolean.TRUE.toString()));
     }
 
     @Override
@@ -273,6 +276,11 @@ public void processOpts() {
         }
         writePropertyBack(PREFIX_PARAMETER_INTERFACES, getPrefixParameterInterfaces());
 
+        if (additionalProperties.containsKey(WITH_REQUEST_OPTS_IN_INTERFACE)) {
+            this.setWithRequestOptsInInterface(convertPropertyToBoolean(WITH_REQUEST_OPTS_IN_INTERFACE));
+        }
+        writePropertyBack(WITH_REQUEST_OPTS_IN_INTERFACE, getWithRequestOptsInInterface());
+
         if (additionalProperties.containsKey(NPM_NAME)) {
             addNpmPackageGeneration();
         }
@@ -1084,6 +1092,14 @@ private void setPrefixParameterInterfaces(boolean prefixParameterInterfaces) {
         this.prefixParameterInterfaces = prefixParameterInterfaces;
     }
 
+    private boolean getWithRequestOptsInInterface() {
+        return withRequestOptsInInterface;
+    }
+
+    private void setWithRequestOptsInInterface(boolean withRequestOptsInInterface) {
+        this.withRequestOptsInInterface = withRequestOptsInInterface;
+    }
+
     private static boolean itemsAreUniqueId(CodegenProperty items) {
         if (items != null && items.items != null) {
             return itemsAreUniqueId(items.items);

modules/openapi-generator/src/main/resources/typescript-fetch/apis.mustache

@@ -42,6 +42,7 @@ export interface {{#prefixParameterInterfaces}}{{classname}}{{/prefixParameterIn
  */
 export interface {{classname}}Interface {
 {{#operation}}
+    {{#withRequestOptsInInterface}}
     /**
      * Creates request options for {{nickname}} without sending the request
      {{#allParams}}
@@ -55,6 +56,7 @@ export interface {{classname}}Interface {
      */
     {{nickname}}RequestOpts({{#allParams.0}}requestParameters: {{#prefixParameterInterfaces}}{{classname}}{{/prefixParameterInterfaces}}{{operationIdCamelCase}}Request{{/allParams.0}}): Promise<runtime.RequestOpts>;
 
+    {{/withRequestOptsInInterface}}
     /**
      * {{&notes}}
      {{#summary}}

modules/openapi-generator/src/test/java/org/openapitools/codegen/options/TypeScriptFetchClientOptionsProvider.java

@@ -53,6 +53,7 @@ public Map<String, String> createOptions() {
                 .put(TypeScriptFetchClientCodegen.STRING_ENUMS, STRING_ENUMS)
                 .put(TypeScriptFetchClientCodegen.USE_SQUARE_BRACKETS_IN_ARRAY_NAMES, Boolean.FALSE.toString())
                 .put(TypeScriptFetchClientCodegen.VALIDATION_ATTRIBUTES, Boolean.FALSE.toString())
+                .put(TypeScriptFetchClientCodegen.WITH_REQUEST_OPTS_IN_INTERFACE, Boolean.TRUE.toString())
                 .build();
     }
 }

modules/openapi-generator/src/test/java/org/openapitools/codegen/typescript/fetch/TypeScriptFetchClientCodegenTest.java

@@ -21,6 +21,7 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -458,6 +459,55 @@ public void testValidationAttributesWithWithoutRuntimeChecks() throws IOExceptio
         TestUtils.assertFileContains(modelsIndex, "[property: string]:");
     }
 
+    @Test(description = "Verify withRequestOptsInInterface=true (default) includes RequestOpts in interface")
+    public void testRequestOptsInInterfaceByDefault() throws IOException {
+        Map<String, Object> properties = new HashMap<>();
+        properties.put(TypeScriptFetchClientCodegen.WITH_INTERFACES, true);
+
+        File output = generate(properties);
+
+        Path apiFile = Paths.get(output + "/apis/PetControllerApi.ts");
+        TestUtils.assertFileExists(apiFile);
+
+        // Read file content and split into interface and class sections
+        String content = new String(Files.readAllBytes(apiFile), StandardCharsets.UTF_8);
+        int interfaceStart = content.indexOf("export interface PetControllerApiInterface");
+        int classStart = content.indexOf("export class PetControllerApi");
+        String interfaceSection = content.substring(interfaceStart, classStart);
+
+        // Interface should contain RequestOpts methods
+        assertThat(interfaceSection).contains("addPetRequestOpts(");
+
+        // Class should also contain RequestOpts methods
+        String classSection = content.substring(classStart);
+        assertThat(classSection).contains("async addPetRequestOpts(");
+    }
+
+    @Test(description = "Verify withRequestOptsInInterface=false excludes RequestOpts from interface but keeps them on class")
+    public void testRequestOptsNotInInterfaceWhenDisabled() throws IOException {
+        Map<String, Object> properties = new HashMap<>();
+        properties.put(TypeScriptFetchClientCodegen.WITH_INTERFACES, true);
+        properties.put(TypeScriptFetchClientCodegen.WITH_REQUEST_OPTS_IN_INTERFACE, false);
+
+        File output = generate(properties);
+
+        Path apiFile = Paths.get(output + "/apis/PetControllerApi.ts");
+        TestUtils.assertFileExists(apiFile);
+
+        // Read file content and split into interface and class sections
+        String content = new String(Files.readAllBytes(apiFile), StandardCharsets.UTF_8);
+        int interfaceStart = content.indexOf("export interface PetControllerApiInterface");
+        int classStart = content.indexOf("export class PetControllerApi");
+        String interfaceSection = content.substring(interfaceStart, classStart);
+
+        // Interface should NOT contain RequestOpts methods
+        assertThat(interfaceSection).doesNotContain("RequestOpts");
+
+        // Class should still contain RequestOpts methods
+        String classSection = content.substring(classStart);
+        assertThat(classSection).contains("async addPetRequestOpts(");
+    }
+
     private static File generate(
         Map<String, Object> properties
     ) throws IOException {