prism/src/main/java/org/apache/falcon/resource/proxy/BufferedRequest.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.falcon.resource.proxy;

import org.apache.falcon.FalconWebException;
import org.apache.hadoop.io.IOUtils;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletInputStream;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import javax.ws.rs.core.Response;
import java.io.*;
import java.security.Principal;
import java.util.Enumeration;
import java.util.Locale;
import java.util.Map;

/**
 * A buffered implementation of HttpServletRequest.
 */
public class BufferedRequest implements HttpServletRequest {

    private final HttpServletRequest request;

    private final ServletInputStream stream;

    private final ThreadLocal<ByteArrayOutputStream> streams =
            new ThreadLocal<ByteArrayOutputStream>() {
                @Override
                protected ByteArrayOutputStream initialValue() {
                    return new ByteArrayOutputStream(2 * 1024);
                }
            };

    public BufferedRequest(HttpServletRequest request) {
        try {
            this.request = request;
            ByteArrayOutputStream copyBuffer = streams.get();
            copyBuffer.reset();
            IOUtils.copyBytes(request.getInputStream(), copyBuffer, 4096, false);
            final ByteArrayInputStream buffer =
                    new ByteArrayInputStream(copyBuffer.toByteArray(), 0, copyBuffer.size());
            stream = new ServletInputStream() {
                @Override
                public int read() throws IOException {
                    return buffer.read();
                }

                @Override
                public void mark(int readlimit) {
                    buffer.mark(readlimit);
                }

                @Override
                public void reset() throws IOException {
                    buffer.reset();
                }

                @Override
                public boolean markSupported() {
                    return buffer.markSupported();
                }
            };
            stream.mark(10 * 1024 * 1024);
        } catch (IOException e) {
            throw FalconWebException.newException(e, Response.Status.INTERNAL_SERVER_ERROR);
        }
    }

    @Override
    public String getAuthType() {
        return request.getAuthType();
    }

    @Override
    public Cookie[] getCookies() {
        return request.getCookies();
    }

    @Override
    public long getDateHeader(String name) {
        return request.getDateHeader(name);
    }

    @Override
    public String getHeader(String name) {
        return request.getHeader(name);
    }

    @Override
    public Enumeration getHeaders(String name) {
        return request.getHeaders(name);
    }

    @Override
    public Enumeration getHeaderNames() {
        return request.getHeaderNames();
    }

    @Override
    public int getIntHeader(String name) {
        return request.getIntHeader(name);
    }

    @Override
    public String getMethod() {
        return request.getMethod();
    }

    @Override
    public String getPathInfo() {
        return request.getPathInfo();
    }

    @Override
    public String getPathTranslated() {
        return request.getPathTranslated();
    }

    @Override
    public String getContextPath() {
        return request.getContextPath();
    }

    @Override
    public String getQueryString() {
        return request.getQueryString();
    }

    @Override
    public String getRemoteUser() {
        return request.getRemoteUser();
    }

    @Override
    public boolean isUserInRole(String role) {
        return request.isUserInRole(role);
    }

    @Override
    public Principal getUserPrincipal() {
        return request.getUserPrincipal();
    }

    @Override
    public String getRequestedSessionId() {
        return request.getRequestedSessionId();
    }

    @Override
    public String getRequestURI() {
        return request.getRequestURI();
    }

    @Override
    public StringBuffer getRequestURL() {
        return request.getRequestURL();
    }

    @Override
    public String getServletPath() {
        return request.getServletPath();
    }

    @Override
    public HttpSession getSession(boolean create) {
        return request.getSession(create);
    }

    @Override
    public HttpSession getSession() {
        return request.getSession();
    }

    @Override
    public boolean isRequestedSessionIdValid() {
        return request.isRequestedSessionIdValid();
    }

    @Override
    public boolean isRequestedSessionIdFromCookie() {
        return request.isRequestedSessionIdFromCookie();
    }

    @Override
    public boolean isRequestedSessionIdFromURL() {
        return request.isRequestedSessionIdFromURL();
    }

    @Override
    public boolean isRequestedSessionIdFromUrl() {
        return request.isRequestedSessionIdFromUrl();
    }

    @Override
    public Object getAttribute(String name) {
        return request.getAttribute(name);
    }

    @Override
    public Enumeration getAttributeNames() {
        return request.getAttributeNames();
    }

    @Override
    public String getCharacterEncoding() {
        return request.getCharacterEncoding();
    }

    @Override
    public void setCharacterEncoding(String env) throws UnsupportedEncodingException {
    }

    @Override
    public int getContentLength() {
        return request.getContentLength();
    }

    @Override
    public String getContentType() {
        return request.getContentType();
    }

    @Override
    public ServletInputStream getInputStream() throws IOException {
        return stream;
    }

    @Override
    public String getParameter(String name) {
        return request.getParameter(name);
    }

    @Override
    public Enumeration getParameterNames() {
        return request.getParameterNames();
    }

    @Override
    public String[] getParameterValues(String name) {
        return request.getParameterValues(name);
    }

    @Override
    public Map getParameterMap() {
        return request.getParameterMap();
    }

    @Override
    public String getProtocol() {
        return request.getProtocol();
    }

    @Override
    public String getScheme() {
        return request.getScheme();
    }

    @Override
    public String getServerName() {
        return request.getServerName();
    }

    @Override
    public int getServerPort() {
        return request.getServerPort();
    }

    @Override
    public BufferedReader getReader() throws IOException {
        return request.getReader();
    }

    @Override
    public String getRemoteAddr() {
        return request.getRemoteAddr();
    }

    @Override
    public String getRemoteHost() {
        return request.getRemoteHost();
    }

    @Override
    public void setAttribute(String name, Object o) {
    }

    @Override
    public void removeAttribute(String name) {
    }

    @Override
    public Locale getLocale() {
        return request.getLocale();
    }

    @Override
    public Enumeration getLocales() {
        return request.getLocales();
    }

    @Override
    public boolean isSecure() {
        return request.isSecure();
    }

    @Override
    public RequestDispatcher getRequestDispatcher(String path) {
        return request.getRequestDispatcher(path);
    }

    @Override
    public String getRealPath(String path) {
        return request.getRealPath(path);
    }

    @Override
    public int getRemotePort() {
        return request.getRemotePort();
    }

    @Override
    public String getLocalName() {
        return request.getLocalName();
    }

    @Override
    public String getLocalAddr() {
        return request.getLocalAddr();
    }

    @Override
    public int getLocalPort() {
        return request.getLocalPort();
    }
}