Experimental compile-time OpenAPI integration for Javalin and Ktor ecosystem.

• Reflection free, does not perform any extra operations at runtime
• Uses @OpenApi to simplify migration from bundled OpenApi implementation
• Supports Java 8+ (also 16 and any further releases) and Kotlin (through Kapt)
• Uses internal WebJar handler that works with /* route out of the box
• Provides better projection of OpenAPI specification
• Schema validation through Swagger core module

Download required dependencies:

repositories {
    maven { url 'https://repo.panda-lang.org/releases' }
}
dependencies {
    def openapi = "1.1.7"
    annotationProcessor "io.javalin-rfc:openapi-annotation-processor:$openapi" // Use Kapt in Kotlin projects 
    
    // Javalin
    implementation "io.javalin-rfc:javalin-openapi-plugin:$openapi"
    implementation "io.javalin-rfc:javalin-swagger-plugin:$openapi" // for Swagger UI
    implementation "io.javalin-rfc:javalin-redoc-plugin:$openapi" // for ReDoc UI
    
    // Ktor
    implementation "io.javalin-rfc:ktor-openapi-plugin:$openapi"
}

And enable OpenAPI plugin for Javalin with Swagger UI:

Javalin.create(config -> {
    String deprecatedDocsPath = "/swagger-docs";
    
    OpenApiConfiguration openApiConfiguration = new OpenApiConfiguration();
    openApiConfiguration.setTitle("AwesomeApp");
    openApiConfiguration.setDocumentationPath(deprecatedDocsPath); // by default it's /openapi
    config.registerPlugin(new OpenApiPlugin(openApiConfiguration));
    
    SwaggerConfiguration swaggerConfiguration = new SwaggerConfiguration();
    swaggerConfiguration.setDocumentationPath(deprecatedDocsPath);
    config.registerPlugin(new SwaggerPlugin(swaggerConfiguration));
    
    ReDocConfiguration reDocConfiguration = new ReDocConfiguration();
    reDocConfiguration.setDocumentationPath(deprecatedDocsPath);
    config.registerPlugin(new ReDocPlugin(reDocConfiguration));
})
.start(80);

Or for Ktor application using the features:

install(OpenApiFeature) {
    documentationPath = "/swagger-docs"
}
// Swagger and ReDoc are not supported yet

• Reposilite with Javalin
• Hub with Ktor
• Javalin OpenApi Example by paulkagiri

• openapi-annotation-processor - compile-time annotation processor, should generate openapi.json resource or just a class
• openapi-annotations - annotations used by annotation processor to generate OpenAPI docs

Javalin:

• javalin-openapi-plugin - loads openapi.json resource and serves OpenApi endpoint
• javalin-swagger-plugin - serves Swagger UI
• javalin-redoc-plugin - serves ReDoc UI
• javalin-apptest - example Javalin application that uses OpenApi plugin

Ktor:

• ktor-openapi-plugin - loads openapi.json resource and serves OpenApi endpoint
• ktor-apptest - example Ktor application that uses OpenApi plugin