feat: [OpenAPI] Type and Import mapping support

datamodel/openapi/openapi-api-sample/pom.xml

@@ -123,6 +123,7 @@
 							<inputSpec>${project.basedir}/src/main/resources/sodastore.yaml</inputSpec>
 							<apiPackage>com.sap.cloud.sdk.datamodel.openapi.sample.api</apiPackage>
 							<modelPackage>com.sap.cloud.sdk.datamodel.openapi.sample.model</modelPackage>
+                            <typeMappings>File=byte[]</typeMappings>
 							<additionalProperties>
 								<pojoBuilderMethodName>create</pojoBuilderMethodName>
 								<pojoBuildMethodName />

datamodel/openapi/openapi-api-sample/src/main/java/com/sap/cloud/sdk/datamodel/openapi/sample/api/SodasApi.java

@@ -57,6 +57,68 @@ public SodasApi( @Nonnull final ApiClient apiClient )
         super(apiClient);
     }
 
+    /**
+     * <p>
+     * Download soda product data as binary
+     * </p>
+     * <p>
+     * </p>
+     * <p>
+     * <b>200</b> - Successful response
+     * <p>
+     * <b>404</b> - Soda product not found
+     *
+     * @param id
+     *            ID of the soda product to download
+     * @return byte[]
+     * @throws OpenApiRequestException
+     *             if an error occurs while attempting to invoke the API
+     */
+    @Nonnull
+    public byte[] sodasDownloadIdGet( @Nonnull final Long id )
+        throws OpenApiRequestException
+    {
+        final Object localVarPostBody = null;
+
+        // verify the required parameter 'id' is set
+        if( id == null ) {
+            throw new OpenApiRequestException("Missing the required parameter 'id' when calling sodasDownloadIdGet");
+        }
+
+        // create path and map variables
+        final Map<String, Object> localVarPathParams = new HashMap<String, Object>();
+        localVarPathParams.put("id", id);
+        final String localVarPath =
+            UriComponentsBuilder.fromPath("/sodas/download/{id}").buildAndExpand(localVarPathParams).toUriString();
+
+        final MultiValueMap<String, String> localVarQueryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders localVarHeaderParams = new HttpHeaders();
+        final MultiValueMap<String, Object> localVarFormParams = new LinkedMultiValueMap<String, Object>();
+
+        final String[] localVarAccepts = { "application/octet-stream" };
+        final List<MediaType> localVarAccept = apiClient.selectHeaderAccept(localVarAccepts);
+        final String[] localVarContentTypes = {};
+        final MediaType localVarContentType = apiClient.selectHeaderContentType(localVarContentTypes);
+
+        final String[] localVarAuthNames = new String[] { "apiKeyAuth", "bearerAuth" };
+
+        final ParameterizedTypeReference<byte[]> localVarReturnType = new ParameterizedTypeReference<byte[]>()
+        {
+        };
+        return apiClient
+            .invokeAPI(
+                localVarPath,
+                HttpMethod.GET,
+                localVarQueryParams,
+                localVarPostBody,
+                localVarHeaderParams,
+                localVarFormParams,
+                localVarAccept,
+                localVarContentType,
+                localVarAuthNames,
+                localVarReturnType);
+    }
+
     /**
      * <p>
      * Get all soda products

datamodel/openapi/openapi-api-sample/src/main/resources/sodastore.yaml

@@ -258,6 +258,29 @@ paths:
                 $ref: '#/components/schemas/SodaWithId'
         '404':
           description: Soda product not found
+  /sodas/download/{id}:
+    get:
+      summary: Download soda product data as binary
+      tags:
+        - Sodas
+      parameters:
+        - name: id
+          in: path
+          description: ID of the soda product to download
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '200':
+          description: Successful response
+          content:
+            application/octet-stream:
+              schema:
+                type: string
+                format: binary
+        '404':
+          description: Soda product not found
   /orders:
     post:
       summary: Create a new order

datamodel/openapi/openapi-api-sample/src/test/java/com/sap/cloud/sdk/datamodel/openapi/sample/api/DeserializationTest.java

@@ -115,6 +115,26 @@ void testUnexpectedAdditionalField()
         assertThat(actual.getCustomField("unexpectedField")).asInstanceOf(InstanceOfAssertFactories.LIST).isEmpty();
     }
 
+    @Test
+    void testBinaryResponse()
+    {
+        final byte[] binaryData = "binary file content".getBytes();
+        WireMock
+            .stubFor(
+                WireMock
+                    .get(WireMock.urlMatching("/sodas/download/\\d+"))
+                    .willReturn(
+                        WireMock
+                            .aResponse()
+                            .withStatus(200)
+                            .withHeader("Content-Type", "application/octet-stream")
+                            .withBody(binaryData)));
+
+        final byte[] result = sut.sodasDownloadIdGet(1L);
+        assertThat(result).isNotNull();
+        assertThat(result).isEqualTo(binaryData);
+    }
+
     private void stub( String responseBody )
     {
         WireMock.stubFor(WireMock.get(WireMock.anyUrl()).willReturn(okJson(responseBody)));

datamodel/openapi/openapi-generator-maven-plugin/src/main/java/com/sap/cloud/sdk/datamodel/openapi/generator/DataModelGeneratorMojo.java

@@ -1,7 +1,12 @@
 package com.sap.cloud.sdk.datamodel.openapi.generator;
 
 import java.util.Arrays;
+import java.util.List;
 import java.util.Map;
+import java.util.Objects;
+import java.util.stream.Collectors;
+
+import javax.annotation.Nonnull;
 
 import org.apache.maven.plugin.AbstractMojo;
 import org.apache.maven.plugin.MojoExecutionException;
@@ -126,6 +131,18 @@ public class DataModelGeneratorMojo extends AbstractMojo
     @Parameter( property = "openapi.generate.generateApis", defaultValue = "true" )
     private boolean generateApis;
 
+    /**
+     * Type mappings to override OpenAPI specification types and the types used in your generated code.
+     */
+    @Parameter( property = "openapi.generate.typeMappings" )
+    private List<String> typeMappings;
+
+    /**
+     * Import mappings to specify alternative imports statement to use for a given class name.
+     */
+    @Parameter( property = "openapi.generate.importMappings" )
+    private List<String> importMappings;
+
     /**
      * Defines a list of additional properties that will be passed to the Java generator.
      */
@@ -189,6 +206,8 @@ Try<GenerationConfiguration> retrieveGenerationConfiguration()
                     .oneOfAnyOfGenerationEnabled(enableOneOfAnyOfGeneration)
                     .generateModels(generateModels)
                     .generateApis(generateApis)
+                    .typeMappings(parseMapping(typeMappings))
+                    .importMappings(parseMapping(importMappings))
                     .build());
     }
 
@@ -198,4 +217,16 @@ void setOutputDirectory( final String outputDirectory )
         this.outputDirectory = outputDirectory;
     }
 
+    @Nonnull
+    private Map<String, String> parseMapping( @Nonnull final List<String> mappings )
+    {
+        return mappings
+            .stream()
+            .filter(Objects::nonNull)
+            .filter(line -> line.contains("="))
+            .map(line -> line.split("=", 2))
+            .map(parts -> new String[] { parts[0].trim(), parts[1].trim() })
+            .filter(parts -> !parts[0].isEmpty() && !parts[1].isEmpty())
+            .collect(Collectors.toMap(parts -> parts[0], parts -> parts[1]));
+    }
 }

datamodel/openapi/openapi-generator-maven-plugin/src/test/java/com/sap/cloud/sdk/datamodel/openapi/generator/DataModelGeneratorMojoUnitTest.java

@@ -30,6 +30,7 @@ class DataModelGeneratorMojoUnitTest
         RESOURCE_PATH + "/testInvocationWithUnexpectedApiMaturity/pom.xml";
     private static final String ADDITIONAL_PROPERTIES_POM =
         RESOURCE_PATH + "/testAdditionalPropertiesAndEnablingAnyOfOneOf/pom.xml";
+    private static final String MAPPINGS_EDGE_CASES_POM = RESOURCE_PATH + "/testMappingsEdgeCases/pom.xml";
 
     @TempDir
     File outputDirectory;
@@ -50,6 +51,11 @@ void testInvocationWithAllParameters( DataModelGeneratorMojo mojo )
         assertThat(configuration.getApiPackage()).isEqualTo("com.sap.cloud.sdk.datamodel.rest.test.api");
         assertThat(configuration.deleteOutputDirectory()).isTrue();
         assertThat(configuration.isOneOfAnyOfGenerationEnabled()).isFalse();
+        assertThat(configuration.getTypeMappings())
+            .containsEntry("binary", "org.springframework.core.io.Resource")
+            .containsEntry("file", "org.springframework.core.io.Resource");
+        assertThat(configuration.getImportMappings())
+            .containsEntry("org.springframework.core.io.Resource", "org.springframework.core.io.Resource");
 
         mojo.setOutputDirectory(outputDirectory.getAbsolutePath());
 
@@ -71,6 +77,8 @@ void testInvocationWithMandatoryParameters( DataModelGeneratorMojo mojo )
         assertThat(configuration.getModelPackage()).isEqualTo("com.sap.cloud.sdk.datamodel.rest.test.model");
         assertThat(configuration.getApiPackage()).isEqualTo("com.sap.cloud.sdk.datamodel.rest.test.api");
         assertThat(configuration.deleteOutputDirectory()).isFalse();
+        assertThat(configuration.getTypeMappings()).isEmpty();
+        assertThat(configuration.getImportMappings()).isEmpty();
 
         mojo.setOutputDirectory(outputDirectory.getAbsolutePath());
 
@@ -126,4 +134,21 @@ void testAdditionalPropertiesAndEnablingAnyOfOneOf( DataModelGeneratorMojo mojo
 
         assertThat(mojo.retrieveGenerationConfiguration().get().isOneOfAnyOfGenerationEnabled()).isTrue();
     }
+
+    @Test
+    @InjectMojo( goal = "generate", pom = MAPPINGS_EDGE_CASES_POM )
+    void testMappingsEdgeCases( DataModelGeneratorMojo mojo )
+        throws Throwable
+    {
+        final GenerationConfiguration configuration = mojo.retrieveGenerationConfiguration().get();
+
+        assertThat(configuration.getTypeMappings())
+            .hasSize(2) // Only valid mappings should remain
+            .containsEntry("File", "byte[]")
+            .containsEntry("binary", "org.springframework.core.io.Resource");
+
+        assertThat(configuration.getImportMappings())
+            .hasSize(1)
+            .containsEntry("Resource", "org.springframework.core.io.Resource");
+    }
 }

datamodel/openapi/openapi-generator-maven-plugin/src/test/resources/DataModelGeneratorMojoUnitTest/testInvocationWithAllParameters/pom.xml

@@ -20,7 +20,14 @@
 					<verbose>true</verbose>
 					<outputDirectory>output-directory</outputDirectory>
 					<deleteOutputDirectory>true</deleteOutputDirectory>
-				</configuration>
+                    <typeMappings>
+                        <typeMapping>binary=org.springframework.core.io.Resource</typeMapping>
+                        <typeMapping>file=org.springframework.core.io.Resource</typeMapping>
+                    </typeMappings>
+                    <importMappings>
+                        <importMapping>org.springframework.core.io.Resource=org.springframework.core.io.Resource</importMapping>
+                    </importMappings>
+                </configuration>
 			</plugin>
 		</plugins>
 	</build>

datamodel/openapi/openapi-generator-maven-plugin/src/test/resources/DataModelGeneratorMojoUnitTest/testMappingsEdgeCases/pom.xml

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.company</groupId>
+    <artifactId>application</artifactId>
+    <version>5.25.0-SNAPSHOT</version>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>com.sap.cloud.sdk.datamodel</groupId>
+                <artifactId>openapi-generator-maven-plugin</artifactId>
+                <configuration>
+                    <inputSpec>DataModelGeneratorMojoUnitTest/testMappingsEdgeCases/input/sodastore.yaml</inputSpec>
+                    <apiPackage>com.sap.cloud.sdk.datamodel.rest.test.api</apiPackage>
+                    <modelPackage>com.sap.cloud.sdk.datamodel.rest.test.model</modelPackage>
+                    <apiMaturity>released</apiMaturity>
+                    <outputDirectory>output-directory</outputDirectory>
+                    <typeMappings>
+                        <typeMapping>File=byte[]</typeMapping>
+                        <typeMapping>binary = org.springframework.core.io.Resource</typeMapping>
+                        <typeMapping>no-equals-sign</typeMapping>
+                        <typeMapping>=missing-key</typeMapping>
+                        <typeMapping>missing-value=</typeMapping>
+                        <typeMapping>=</typeMapping>
+                        <typeMapping></typeMapping><!-- Invalid: empty -->
+                    </typeMappings>
+                    <importMappings>
+                        <importMapping>Resource=org.springframework.core.io.Resource</importMapping>
+                        <importMapping>no-equals-sign</importMapping>
+                    </importMappings>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+</project>

datamodel/openapi/openapi-generator/src/main/java/com/sap/cloud/sdk/datamodel/openapi/generator/GenerationConfigurationConverter.java

@@ -65,6 +65,8 @@ static ClientOptInput convertGenerationConfiguration(
         config.setModelPackage(generationConfiguration.getModelPackage());
         config.setTemplateDir(TEMPLATE_DIRECTORY);
         config.additionalProperties().putAll(getAdditionalProperties(generationConfiguration));
+        config.typeMapping().putAll(generationConfiguration.getTypeMappings());
+        config.importMapping().putAll(generationConfiguration.getImportMappings());
 
         final var openAPI = parseOpenApiSpec(inputSpecFile, generationConfiguration);
 

datamodel/openapi/openapi-generator/src/main/java/com/sap/cloud/sdk/datamodel/openapi/generator/model/GenerationConfiguration.java

@@ -61,6 +61,12 @@ public class GenerationConfiguration
     @Builder.Default
     boolean debugModels = false;
 
+    @Singular( ignoreNullCollections = true )
+    Map<String, String> typeMappings;
+
+    @Singular( ignoreNullCollections = true )
+    Map<String, String> importMappings;
+
     /**
      * Indicates whether to use the default SAP copyright header for generated files.
      *

datamodel/openapi/openapi-generator/src/test/java/com/sap/cloud/sdk/datamodel/openapi/generator/GenerationConfigurationConverterTest.java

@@ -4,11 +4,13 @@
 
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.util.Map;
 
 import javax.annotation.Nullable;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
+import org.openapitools.codegen.ClientOptInput;
 
 import com.sap.cloud.sdk.datamodel.openapi.generator.model.GenerationConfiguration;
 
@@ -57,4 +59,22 @@ private String getCopyrightHeaderFromConfig( final GenerationConfiguration confi
                 .get(GenerationConfigurationConverter.COPYRIGHT_PROPERTY_KEY);
         return maybeHeader != null ? maybeHeader.toString() : null;
     }
+
+    @Test
+    @SuppressWarnings( "deprecation" )
+    void testTypeMappingsAndImportMappingsAreApplied()
+    {
+        final Map<String, String> typeMappings =
+            Map.of("File", "byte[]", "binary", "org.springframework.core.io.Resource");
+        final Map<String, String> importMappings = Map.of("Resource", "org.springframework.core.io.Resource");
+
+        final GenerationConfiguration config =
+            createBasicConfig().typeMappings(typeMappings).importMappings(importMappings).build();
+
+        final ClientOptInput result =
+            GenerationConfigurationConverter.convertGenerationConfiguration(config, Paths.get(config.getInputSpec()));
+
+        assertThat(result.getConfig().typeMapping()).containsAllEntriesOf(typeMappings);
+        assertThat(result.getConfig().importMapping()).containsAllEntriesOf(importMappings);
+    }
 }