HTTP Integration

/**
 * JAX-RS response filter for Quarkus REST metrics collection
 * Automatically collects timing and request count metrics for REST endpoints
 */
@ServerResponseFilter
public class QuarkusRestMetricsFilter {
    // Filter is automatically applied to Quarkus REST endpoints
    // No public methods - integration is annotation-based
}

// Filter is automatically applied when the extension is present
// No explicit configuration needed - metrics are collected automatically

@Path("/api")
public class MyResource {
    
    @GET
    @Path("/users")
    public List<User> getUsers() {
        // Metrics automatically collected:
        // - REST.request timer (execution time)
        // - Request count by status code
        return userService.getAllUsers();
    }
}

/**
 * JAX-RS filter for RESTEasy metrics collection
 * Implements both request and response filtering
 */
public class QuarkusRestEasyMetricsFilter 
    implements ContainerRequestFilter, ContainerResponseFilter {
    
    /** Filter incoming requests to start timing */
    public void filter(ContainerRequestContext requestContext);
    
    /** Filter outgoing responses to complete timing and record metrics */
    public void filter(
        ContainerRequestContext requestContext,
        ContainerResponseContext responseContext
    );
}

// Filter is automatically applied when using RESTEasy Classic
// Metrics are collected for all JAX-RS endpoints

@Path("/api/v1")
public class LegacyResource {
    
    @GET
    @Path("/products")
    public Response getProducts() {
        // Metrics automatically collected:
        // - Request timing
        // - Response status codes
        // - Request counts
        return Response.ok(productService.getAllProducts()).build();
    }
}

/**
 * Vert.x handler for metrics endpoint exposure
 * Handles HTTP requests to the metrics endpoint
 */
public class SmallRyeMetricsHandler implements Handler<RoutingContext> {
    /** Configure the metrics endpoint path */
    public void setMetricsPath(String metricsPath);
    
    /** Handle incoming HTTP requests for metrics */
    public void handle(RoutingContext routingContext);
}

import io.quarkus.smallrye.metrics.runtime.SmallRyeMetricsHandler;
import io.vertx.ext.web.RoutingContext;

// Typically configured by the extension deployment processor
SmallRyeMetricsHandler handler = new SmallRyeMetricsHandler();
handler.setMetricsPath("/custom-metrics");

// Handler processes requests to metrics endpoint
// Returns metrics in Prometheus format by default
// Supports JSON format via Accept: application/json header

// Metrics automatically created:
// - REST.request timer per endpoint
// - Request counts by HTTP status code
// - Response time percentiles
// - Exception counts

// Timer naming pattern:
// REST.request.{class}.{method}
// Tags: class, method, uri, status

// Example metric names:
// REST.request.com_example_UserResource_getUsers_GET
// REST.request.com_example_ProductResource_createProduct_POST

// Tags applied to REST metrics:
Tag.of("class", "com.example.UserResource")
Tag.of("method", "getUsers") 
Tag.of("uri", "/api/users")
Tag.of("status", "200")

// Default endpoint: /q/metrics
// Configurable via: quarkus.smallrye-metrics.path

// Response formats:
// - Prometheus format (default, text/plain)
// - JSON format (Accept: application/json)

// Example Prometheus output:
// # TYPE REST_request_total counter
// REST_request_total{class="UserResource",method="getUsers",status="200"} 42
//
// # TYPE REST_request_seconds summary  
// REST_request_seconds{class="UserResource",method="getUsers",quantile="0.5"} 0.123

// Handler is registered by the deployment processor
// Typically at build time via SmallRyeMetricsRecorder

// Example registration (internal):
Router router = Router.router(vertx);
SmallRyeMetricsHandler handler = recorder.handler("/q/metrics");
router.get("/q/metrics").handler(handler);

// Enable/disable JAX-RS metrics collection
// quarkus.smallrye-metrics.jaxrs.enabled=true|false

// When disabled, REST endpoint metrics are not collected
// Application and base metrics remain available

// Default metrics path: /q/metrics
// Custom path via configuration:
// quarkus.smallrye-metrics.path=/custom-metrics

SmallRyeMetricsHandler handler = new SmallRyeMetricsHandler();
handler.setMetricsPath("/custom-metrics");

// JAX-RS Types
interface ContainerRequestFilter {
    void filter(ContainerRequestContext requestContext);
}

interface ContainerResponseFilter {
    void filter(
        ContainerRequestContext requestContext,
        ContainerResponseContext responseContext
    );
}

// Vert.x Types  
interface Handler<T> {
    void handle(T event);
}

class RoutingContext {
    HttpServerRequest request();
    HttpServerResponse response();
    void next();
    void fail(int statusCode);
}