Add userDefinedTemplateFiles option to maven generator plugin

modules/openapi-generator-maven-plugin/src/main/java/org/openapitools/codegen/plugin/CodeGenMojo.java

@@ -151,6 +151,12 @@ public class CodeGenMojo extends AbstractMojo {
     @Parameter(name = "templateResourcePath", property = "openapi.generator.maven.plugin.templateResourcePath")
     private String templateResourcePath;
 
+    /**
+     * Specifies userDefinedTemplates relative to templateDir, see Customizing for more info
+     */
+    @Parameter(name = "userDefinedTemplateFiles")
+    private List<String> userDefinedTemplateFiles;
+
     /**
      * The name of templating engine to use, "mustache" (default) or "handlebars" (beta)
      */
@@ -723,6 +729,7 @@ public void execute() throws MojoExecutionException {
                 configurator.setApiNameSuffix(apiNameSuffix);
             }
 
+
             if (null != templateDirectory) {
                 configurator.setTemplateDir(templateDirectory.getAbsolutePath());
             }
@@ -937,6 +944,10 @@ public void execute() throws MojoExecutionException {
                 }
             }
 
+            if(userDefinedTemplateFiles != null && userDefinedTemplateFiles.size() > 0) {
+                applyUserDefinedTemplateFilesKvpList(userDefinedTemplateFiles, configurator);
+            }
+
             final ClientOptInput input = configurator.toClientOptInput();
             final CodegenConfig config = input.getConfig();
 

modules/openapi-generator-maven-plugin/src/test/java/org/openapitools/codegen/plugin/CodeGenMojoTest.java

@@ -33,6 +33,7 @@
 import org.eclipse.aether.repository.LocalRepository;
 
 import java.io.File;
+import java.io.FileWriter;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -255,6 +256,18 @@ public void test_skipIfSpecIsUnchanged_recognizesUpdatesInExternalReferencedFile
         assertTrue("Src directory should have been regenerated", Files.exists(generatedDir.resolve("src")));
     }
 
+    public void test_userTemplateFiles() throws Exception {
+
+        final Path tempDir = newTempFolder();
+        final CodeGenMojo mojo = loadMojo(tempDir, "src/test/resources/user-defined-templates", null);
+
+        mojo.execute();
+
+        assertTrue(Files.exists(tempDir.resolve(
+                "target/generated-sources/common-maven/remote-openapi/src/main/java/remote/org/openapitools/client/model/CategoryCustom.java"
+        )));
+    }
+
     protected CodeGenMojo loadMojo(Path temporaryFolder, String projectRoot, String profile) throws Exception {
         return loadMojo(temporaryFolder, projectRoot, profile, "default");
     }

modules/openapi-generator-maven-plugin/src/test/resources/default/pom.xml

@@ -55,6 +55,12 @@
                 </dependency>
             </dependencies>
         </profile>
+        <profile>
+            <id>user-templates</id>
+            <properties>
+                <inputSpec>${basedir}/src/main/resources/petstore.yaml</inputSpec>
+            </properties>
+        </profile>
     </profiles>
     <build>
         <finalName>common-maven</finalName>

modules/openapi-generator-maven-plugin/src/test/resources/user-defined-templates/_merged_spec.yaml

@@ -0,0 +1,37 @@
+---
+servers:
+- url: "http://localhost:8080"
+openapi: "3.0.0"
+paths:
+  /pet:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1pet"
+  /user/{username}:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1user~1{username}"
+  /pet/findByStatus:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1pet~1findByStatus"
+  /user/createWithList:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1user~1createWithList"
+  /pet/{petId}/uploadImage:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1pet~1{petId}~1uploadImage"
+  /store/inventory:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1store~1inventory"
+  /user/login:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1user~1login"
+  /user:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1user"
+  /user/createWithArray:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1user~1createWithArray"
+  /pet/findByTags:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1pet~1findByTags"
+  /store/order:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1store~1order"
+  /user/logout:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1user~1logout"
+  /pet/{petId}:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1pet~1{petId}"
+  /store/order/{orderId}:
+    $ref: "./src\\main\\resources\\petstore.yaml#/paths/~1store~1order~1{orderId}"
+info:
+  title: "merged spec"
+  description: "merged spec"
+  version: "1.0.0"

modules/openapi-generator-maven-plugin/src/test/resources/user-defined-templates/local-repo/petstore/schema/1/schema-1.pom

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>petstore</groupId>
+  <artifactId>schema</artifactId>
+  <version>1</version>
+  <description>POM was created from install:install-file</description>
+</project>

modules/openapi-generator-maven-plugin/src/test/resources/user-defined-templates/local-repo/petstore/schema/maven-metadata-local.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<metadata>
+  <groupId>petstore</groupId>
+  <artifactId>schema</artifactId>
+  <versioning>
+    <release>1</release>
+    <versions>
+      <version>1</version>
+    </versions>
+    <lastUpdated>20210724220722</lastUpdated>
+  </versioning>
+</metadata>

modules/openapi-generator-maven-plugin/src/test/resources/user-defined-templates/pom.xml

@@ -0,0 +1,62 @@
+<!--
+  ~ Copyright 2020, 2021 OpenAPI-Generator Contributors (https://openapi-generator.tech)
+  ~
+  ~ 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
+  ~
+  ~     http://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.
+  -->
+
+<project>
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>common.maven</groupId>
+    <artifactId>common-maven</artifactId>
+    <packaging>jar</packaging>
+    <version>1.0.0-SNAPSHOT</version>
+    <name>OpenAPI Generator Configuration Test</name>
+    <url>https://openapi-generator.tech/</url>
+    <build>
+        <finalName>common-maven</finalName>
+        <plugins>
+            <plugin>
+                <groupId>org.openapitools</groupId>
+                <artifactId>openapi-generator-maven-plugin</artifactId>
+                <configuration>
+                    <inputSpec>${basedir}/src/main/resources/petstore.yaml</inputSpec>
+                    <generatorName>java</generatorName>
+                    <configOptions>
+                        <dateLibrary>joda</dateLibrary>
+                    </configOptions>
+                    <apiNameSuffix>Suffix</apiNameSuffix>
+                    <library>jersey2</library>
+                    <output>${basedir}/target/generated-sources/common-maven/remote-openapi</output>
+                    <apiPackage>remote.org.openapitools.client.api</apiPackage>
+                    <modelPackage>remote.org.openapitools.client.model</modelPackage>
+                    <invokerPackage>remote.org.openapitools.client</invokerPackage>
+                    <collapsedSpec>petstore-full-spec</collapsedSpec>
+                    <includeCollapsedSpecInArtifacts>true</includeCollapsedSpecInArtifacts>
+                    <templateDirectory>${basedir}/templates</templateDirectory>
+                    <userDefinedTemplateFiles>
+                        <userDefinedTemplateFile>templateFile=modeltest.mustache,templateType=models,destinationFilename=Custom.java</userDefinedTemplateFile>
+                    </userDefinedTemplateFiles>
+                </configuration>
+                <executions>
+                    <execution>
+                        <id>executionId</id>
+                        <phase>generate-sources</phase>
+                        <goals>
+                            <goal>generate</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+</project>

modules/openapi-generator-maven-plugin/src/test/resources/user-defined-templates/settings.xml

@@ -0,0 +1,11 @@
+<settings>
+    <activeProfiles>
+        <activeProfile>default</activeProfile>
+    </activeProfiles>
+    <profiles>
+        <profile>
+            <id>default</id>
+            <localRepository>${basedir}/local-repo</localRepository>
+        </profile>
+    </profiles>
+</settings>

modules/openapi-generator-maven-plugin/src/test/resources/user-defined-templates/src/main/java/com/example/Example.java

@@ -0,0 +1,7 @@
+package com.example;
+
+public class Example {
+    public static void main(String[] args) {
+        System.out.println("You did it!");
+    }
+}