PipelineUtils.java

/**
 * Copyright 2012 Ronen Hamias, Anton Kharenko
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 */
package io.scalecube.socketio.pipeline;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufAllocator;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.HttpHeaderNames;
import io.netty.handler.codec.http.HttpHeaderValues;
import io.netty.handler.codec.http.HttpMessage;
import io.netty.handler.codec.http.HttpRequest;
import io.netty.handler.codec.http.HttpResponse;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http.HttpUtil;
import io.netty.handler.codec.http.HttpVersion;
import io.netty.handler.codec.http.QueryStringDecoder;
import io.netty.util.CharsetUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.util.List;
import java.util.Map;

/**
 * Utilities methods class. 
 *
 * @author Anton Kharenko
 *
 */
final class PipelineUtils {

  private static final Logger log = LoggerFactory.getLogger(PipelineUtils.class);

  /**
   * Don't let anyone instantiate this class.
   */
  private PipelineUtils() {
  }

  public static String getSessionId(final String requestPath) {
    String[] parts = requestPath.split("[/]");

    if (parts.length > 4 && !parts[4].isEmpty()) {
      String[] idsplit = parts[4].split("[?]");

      if (idsplit[0] != null && idsplit[0].length() > 0) {
        return idsplit[0];
      }

      return parts[4];
    }

    return null;
  }

  public static String getOrigin(final HttpRequest req) {
    return req.headers().get(HttpHeaderNames.ORIGIN);
  }

  public static String extractParameter(QueryStringDecoder queryDecoder, String key) {
    final Map<String, List<String>> params = queryDecoder.parameters();
    List<String> paramsByKey = params.get(key);
    return (paramsByKey != null) ? paramsByKey.get(0) : null;
  }

  public static HttpResponse createHttpResponse(final String origin, ByteBuf content, boolean json) {
    FullHttpResponse res = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK, content);
    if (json) {
      res.headers().add(HttpHeaderNames.CONTENT_TYPE, "text/javascript; charset=UTF-8");
    } else {
      res.headers().add(HttpHeaderNames.CONTENT_TYPE, "text/plain; charset=UTF-8");
    }
    res.headers().add(HttpHeaderNames.CONNECTION, HttpHeaderValues.KEEP_ALIVE);
    if (origin != null) {
      res.headers().add(HttpHeaderNames.ACCESS_CONTROL_ALLOW_ORIGIN, origin);
      res.headers().add(HttpHeaderNames.ACCESS_CONTROL_ALLOW_CREDENTIALS, "true");
    }
    HttpUtil.setContentLength(res, content.readableBytes());

    return res;
  }

  public static ByteBuf copiedBuffer(ByteBufAllocator allocator, String message) {
    ByteBuf buffer = allocator.buffer();
    buffer.writeBytes(message.getBytes(CharsetUtil.UTF_8));
    return buffer;
  }

  public static SocketAddress resolveClientIpByRemoteAddressHeader(HttpMessage message, String headerName) {
    SocketAddress clientIp = null;
    if (headerName != null && !headerName.trim().isEmpty()) {
      String ip = null;
      try {
        ip = message.headers().get(headerName);
        if (ip != null) {
          ip = ip.split(",")[0]; // to handle multiple proxies case (e.g. X-Forwarded-For: client, proxy1, proxy2)
          clientIp = new InetSocketAddress(InetAddress.getByName(ip), 0);
        }
      } catch (Exception e) {
        log.warn("Failed to parse IP address: {} from http header: {}", ip, headerName);
      }
    }
    return clientIp;
  }

}