/*
 * Copyright (c) 2011-2019 Contributors to the Eclipse Foundation
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
 * which is available at https://www.apache.org/licenses/LICENSE-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
 */

package io.vertx.core.spi.metrics;

import io.vertx.core.http.WebSocket;
import io.vertx.core.net.SocketAddress;
import io.vertx.core.spi.observability.HttpRequest;
import io.vertx.core.spi.observability.HttpResponse;

The http client metrics SPI that Vert.x will use to call when http client events occur.

The thread model for the http server metrics depends on the actual context thats started the server.

Event loop context
 Unless specified otherwise, all the methods on this object including the methods inherited from the super interfaces are invoked with the thread of the http client and therefore are the same than the VertxMetrics createMetrics method that created and returned this metrics object. 
Worker context
Unless specified otherwise, all the methods on this object including the methods inherited from the super interfaces are invoked
with a worker thread.
Author:
Nick Scavelli/**
 * The http client metrics SPI that Vert.x will use to call when http client events occur.<p/>
 *
 * The thread model for the http server metrics depends on the actual context thats started the server.<p/>
 *
 * <h3>Event loop context</h3>
 *
 * Unless specified otherwise, all the methods on this object including the methods inherited from the super interfaces are invoked
 * with the thread of the http client and therefore are the same than the
 * {@link io.vertx.core.spi.metrics.VertxMetrics} {@code createMetrics} method that created and returned
 * this metrics object.
 *
 * <h3>Worker context</h3>
 *
 * Unless specified otherwise, all the methods on this object including the methods inherited from the super interfaces are invoked
 * with a worker thread.
 *
 * @author <a href="mailto:nscavell@redhat.com">Nick Scavelli</a>
 */
public interface HttpClientMetrics<R, W, S, T> extends TCPMetrics<S> {

  
Provides metrics for a particular endpoint
Params:
remoteAddress – the endpoint remote address
maxPoolSize – the server max pool size
Returns:
the endpoint metric/**
   * Provides metrics for a particular endpoint
   *
   * @param remoteAddress the endpoint remote address
   * @param maxPoolSize the server max pool size
   * @return the endpoint metric
   */
  default ClientMetrics<R, T, HttpRequest, HttpResponse> createEndpointMetrics(SocketAddress remoteAddress, int maxPoolSize) {
    return null;
  }

  
Called when a connection is made to a endpoint.
 @param endpointMetric the endpoint metric
/**
   * Called when a connection is made to a endpoint.
   *  @param endpointMetric the endpoint metric
   *
   */
  default void endpointConnected(ClientMetrics<R, T, ?, ?> endpointMetric) {
  }

  
Called when a connection to an endpoint is closed.
 @param endpointMetric the endpoint metric
/**
   * Called when a connection to an endpoint is closed.
   *  @param endpointMetric the endpoint metric
   *
   */
  default void endpointDisconnected(ClientMetrics<R, T, ?, ?> endpointMetric) {
  }

  
Called when a web socket connects.
Params:
webSocket – the server web socket
Returns:
the web socket metric/**
   * Called when a web socket connects.
   *
   * @param webSocket the server web socket
   * @return the web socket metric
   */
  default W connected(WebSocket webSocket) {
    return null;
  }

  
Called when the web socket has disconnected.
Params:
webSocketMetric – the web socket metric/**
   * Called when the web socket has disconnected.
   *
   * @param webSocketMetric the web socket metric
   */
  default void disconnected(W webSocketMetric) {
  }
}