# Vert.x OpenAPI Router

Vert.x OpenAPI Router is based on Vert.x OpenAPI and only provides the router functionality.

Vert.x OpenAPI Router can:

- generate a router according to your OpenAPI contract, with correct paths & methods.

## Using Vert.x OpenAPI Router

To use Vert.x OpenAPI Router, add the following dependency to the dependencies section of your build descriptor:

- Maven (in your `pom.xml`):

    <dependency>
     <groupId>io.vertx</groupId>
     <artifactId>vertx-web-openapi-router</artifactId>
     <version>4.4.3</version>
    </dependency>

- Gradle (in your `build.gradle` file):

    dependencies {
     compile 'io.vertx:vertx-web-openapi-router:4.4.3'
    }

## RouterBuilder

With the `RouterBuilder` you can easily generate a Vert.x Web Router based on the passed `OpenAPIContract`.

    OpenAPIContract contract = getContract();
    RouterBuilder routerBuilder = RouterBuilder.create(vertx, contract);
    Router router = routerBuilder.createRouter();

    // In case that a BodyHandler was applied before, it is necessary to pass a RequestExtractor
    RouterBuilder.create(vertx, contract, RequestExtractor.withBodyHandler());

The `RouterBuilder` provides methods to access the generated routes. These routes can then be customized by adding custom handlers or enable / disable the validation.

    OpenAPIRoute getPetsRoute = routerBuilder.getRoute("getPets");

    // Disables validation for this route.
    getPetsRoute.setDoValidation(false);

    for (OpenAPIRoute route : routerBuilder.getRoutes()) {
      // Access the operation object from the contract
      Operation operation = route.getOperation();

      // Add a custom handler
      route.addHandler(routingContext -> {
        // do something
      });

      // Add a failure handler
      route.addFailureHandler(routingContext -> {
        // do something
      });
    }

After a successful validation of the incoming request, the validated parameters and request body are stored in the RoutingContext and can be accessed inside your custom handlers.

    OpenAPIRoute putPetRoute = routerBuilder.getRoute("putPet");

    putPetRoute.addHandler(routingContext -> {
      ValidatedRequest validatedRequest =
        routingContext.get(RouterBuilder.KEY_META_DATA_VALIDATED_REQUEST);

      validatedRequest.getBody(); // returns the body
      validatedRequest.getHeaders(); // returns the header
      // ..
      // ..
    });