[Enhancement] [Gradle Plugin] Allow templates from classpath (#14909)

* [Enhancement] [Gradle Plugin] Allow templates from classpath

* Adding missing argument binding.

modules/openapi-generator-gradle-plugin/README.adoc

@@ -174,6 +174,10 @@ apply plugin: 'org.openapi.generator'
 |None
 |The template directory holding a custom template.
 
+|templateResourcePath
+|String
+|Directory with mustache templates via resource path. This option will overwrite any option defined in `templateDir`
+
 |auth
 |String
 |None

modules/openapi-generator-gradle-plugin/src/main/kotlin/org/openapitools/generator/gradle/plugin/OpenApiGeneratorPlugin.kt

@@ -100,6 +100,7 @@ class OpenApiGeneratorPlugin : Plugin<Project> {
  inputSpecRootDirectory.set(generate.inputSpecRootDirectory)
  remoteInputSpec.set(generate.remoteInputSpec)
  templateDir.set(generate.templateDir)
+ templateResourcePath.set(generate.templateResourcePath)
  auth.set(generate.auth)
  globalProperties.set(generate.globalProperties)
  configFile.set(generate.configFile)

modules/openapi-generator-gradle-plugin/src/main/kotlin/org/openapitools/generator/gradle/plugin/extensions/OpenApiGeneratorGenerateExtension.kt

@@ -69,6 +69,11 @@ open class OpenApiGeneratorGenerateExtension(project: Project) {
  */
  val templateDir = project.objects.property<String?>()
 
+ /**
+ * The template location (which may be a directory or a classpath location) holding custom templates.
+ */
+ val templateResourcePath = project.objects.property<String?>()
+
  /**
  * Adds authorization headers when fetching the OpenAPI definitions remotely.
  * Pass in a URL-encoded string of name:header with a comma separating multiple values

modules/openapi-generator-gradle-plugin/src/main/kotlin/org/openapitools/generator/gradle/plugin/tasks/GenerateTask.kt

@@ -133,6 +133,13 @@ open class GenerateTask @Inject constructor(private val objectFactory: ObjectFac
  @PathSensitive(PathSensitivity.RELATIVE)
  val templateDir = project.objects.property<String?>()
 
+ /**
+ * Resource path containing template files.
+ */
+ @Optional
+ @Input
+ val templateResourcePath = project.objects.property<String?>()
+
  /**
  * Adds authorization headers when fetching the OpenAPI definitions remotely.
  * Pass in a URL-encoded string of name:header with a comma separating multiple values
@@ -707,6 +714,13 @@ open class GenerateTask @Inject constructor(private val objectFactory: ObjectFac
  configurator.setTemplateDir(value)
  }
 
+ templateResourcePath.ifNotEmpty { value ->
+ templateDir.ifNotEmpty {
+ logger.warn("Both templateDir and templateResourcePath were configured. templateResourcePath overwrites templateDir.")
+ }
+ configurator.setTemplateDir(value)
+ }
+
  packageName.ifNotEmpty { value ->
  configurator.setPackageName(value)
  }