com.eucalyptus.ws.handlers.RestfulMarshallingHandler.java Source code

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/*************************************************************************
 * Copyright 2009-2013 Eucalyptus Systems, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 3 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see http://www.gnu.org/licenses/.
 *
 * Please contact Eucalyptus Systems, Inc., 6755 Hollister Ave., Goleta
 * CA 93117, USA or visit http://www.eucalyptus.com/licenses/ if you need
 * additional information or have any questions.
 *
 * This file may incorporate work covered under the following copyright
 * and permission notice:
 *
 *   Software License Agreement (BSD License)
 *
 *   Copyright (c) 2008, Regents of the University of California
 *   All rights reserved.
 *
 *   Redistribution and use of this software in source and binary forms,
 *   with or without modification, are permitted provided that the
 *   following conditions are met:
 *
 *     Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *     Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer
 *     in the documentation and/or other materials provided with the
 *     distribution.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *   COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 *   INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 *   BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 *   CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *   LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 *   ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *   POSSIBILITY OF SUCH DAMAGE. USERS OF THIS SOFTWARE ACKNOWLEDGE
 *   THE POSSIBLE PRESENCE OF OTHER OPEN SOURCE LICENSED MATERIAL,
 *   COPYRIGHTED MATERIAL OR PATENTED MATERIAL IN THIS SOFTWARE,
 *   AND IF ANY SUCH MATERIAL IS DISCOVERED THE PARTY DISCOVERING
 *   IT MAY INFORM DR. RICH WOLSKI AT THE UNIVERSITY OF CALIFORNIA,
 *   SANTA BARBARA WHO WILL THEN ASCERTAIN THE MOST APPROPRIATE REMEDY,
 *   WHICH IN THE REGENTS' DISCRETION MAY INCLUDE, WITHOUT LIMITATION,
 *   REPLACEMENT OF THE CODE SO IDENTIFIED, LICENSING OF THE CODE SO
 *   IDENTIFIED, OR WITHDRAWAL OF THE CODE CAPABILITY TO THE EXTENT
 *   NEEDED TO COMPLY WITH ANY SUCH LICENSES OR RIGHTS.
 ************************************************************************/

package com.eucalyptus.ws.handlers;

import java.io.BufferedOutputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.MissingFormatArgumentException;
import java.util.zip.DeflaterOutputStream;
import java.util.zip.GZIPOutputStream;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import org.apache.log4j.Logger;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.Channels;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.handler.codec.http.DefaultHttpChunk;
import org.jboss.netty.handler.codec.http.DefaultHttpResponse;
import org.jboss.netty.handler.codec.http.HttpChunk;
import org.jboss.netty.handler.codec.http.HttpHeaders;
import org.jboss.netty.handler.codec.http.HttpMessage;
import org.jboss.netty.handler.codec.http.HttpResponseStatus;
import org.jboss.netty.handler.codec.http.HttpVersion;
import com.eucalyptus.binding.Binding;
import com.eucalyptus.binding.BindingException;
import com.eucalyptus.binding.BindingManager;
import com.eucalyptus.binding.HoldMe;
import com.eucalyptus.component.ComponentId;
import com.eucalyptus.component.annotation.ComponentPart;
import com.eucalyptus.context.Context;
import com.eucalyptus.context.Contexts;
import com.eucalyptus.http.MappingHttpRequest;
import com.eucalyptus.http.MappingHttpResponse;
import com.eucalyptus.records.Logs;
import com.eucalyptus.ws.EucalyptusWebServiceException;
import com.eucalyptus.ws.protocol.RequiredQueryParams;
import com.google.common.base.Objects;
import com.google.common.base.Splitter;
import com.google.common.collect.Iterables;
import edu.ucsb.eucalyptus.msgs.BaseMessage;
import edu.ucsb.eucalyptus.msgs.EucalyptusErrorMessageType;
import edu.ucsb.eucalyptus.msgs.ExceptionResponseType;

public abstract class RestfulMarshallingHandler extends MessageStackHandler {
    private static Logger LOG = Logger.getLogger(RestfulMarshallingHandler.class);
    private String namespace;
    private final String namespacePattern;
    private Binding defaultBinding = BindingManager.getDefaultBinding();
    private Binding binding;
    private final Class<? extends ComponentId> component;

    public RestfulMarshallingHandler(String namespacePattern) {
        this.namespacePattern = namespacePattern;
        this.component = getClass().getAnnotation(ComponentPart.class) == null ? null
                : getClass().getAnnotation(ComponentPart.class).value();
        try {
            this.setNamespace(String.format(namespacePattern));
        } catch (MissingFormatArgumentException ex) {
        }
    }

    public RestfulMarshallingHandler(String namespacePattern, String defaultVersion) {
        this(namespacePattern);
        final String defaultBindingNamespace = String.format(namespacePattern, defaultVersion);
        this.defaultBinding = BindingManager.getBinding(BindingManager.sanitizeNamespace(defaultBindingNamespace),
                component);
    }

    @Override
    public void incomingMessage(MessageEvent event) throws Exception {
        if (event.getMessage() instanceof MappingHttpRequest) {
            MappingHttpRequest httpRequest = (MappingHttpRequest) event.getMessage();
            String bindingVersion = httpRequest.getParameters().remove(RequiredQueryParams.Version.toString());
            if (bindingVersion.matches("\\d\\d\\d\\d-\\d\\d-\\d\\d")) {
                this.setNamespaceVersion(bindingVersion);
            } else {
                this.setNamespace(BindingManager.defaultBindingName());
            }
            try {
                BaseMessage msg = (BaseMessage) this.bind(httpRequest);
                httpRequest.setMessage(msg);
            } catch (Exception e) {
                if (!(e instanceof BindingException)) {
                    e = new BindingException(e);
                }
                throw e;
            }
        }
    }

    protected void setNamespace(String namespace) {
        this.namespace = namespace;
        this.binding = BindingManager.getBinding(this.namespace, component);
    }

    protected String getNamespaceForVersion(String bindingVersion) {
        return String.format(this.namespacePattern, bindingVersion);
    }

    private void setNamespaceVersion(String bindingVersion) {
        String newNs = null;
        try {
            newNs = String.format(this.namespacePattern);
        } catch (MissingFormatArgumentException e) {
            newNs = String.format(this.namespacePattern, bindingVersion);
        }
        this.setNamespace(newNs);
    }

    public abstract Object bind(MappingHttpRequest httpRequest) throws Exception;

    @Override
    public void outgoingMessage(ChannelHandlerContext ctx, MessageEvent event) throws Exception {
        if (event.getMessage() instanceof MappingHttpResponse) {
            MappingHttpResponse httpResponse = (MappingHttpResponse) event.getMessage();
            ByteArrayOutputStream byteOut = new ByteArrayOutputStream(8192);
            HoldMe.canHas.lock();
            try {
                if (httpResponse.getMessage() == null) {
                    /** TODO:GRZE: doing nothing here may be needed for streaming? double check... **/
                    //          String response = Binding.createRestFault( this.requestType.get( ctx.getChannel( ) ), "Recieved an response from the service which has no content.", "" );
                    //          byteOut.write( response.getBytes( ) );
                    //          httpResponse.setStatus( HttpResponseStatus.INTERNAL_SERVER_ERROR );
                } else if (httpResponse.getMessage() instanceof EucalyptusErrorMessageType) {
                    EucalyptusErrorMessageType errMsg = (EucalyptusErrorMessageType) httpResponse.getMessage();
                    byteOut.write(Binding
                            .createRestFault(errMsg.getSource(), errMsg.getMessage(), errMsg.getCorrelationId())
                            .getBytes());
                    httpResponse.setStatus(HttpResponseStatus.BAD_REQUEST);
                } else if (httpResponse.getMessage() instanceof ExceptionResponseType) {//handle error case specially
                    ExceptionResponseType msg = (ExceptionResponseType) httpResponse.getMessage();
                    String detail = msg.getError();
                    if (msg.getException() != null) {
                        Logs.extreme().debug(msg, msg.getException());
                    }
                    if (msg.getException() instanceof EucalyptusWebServiceException) {
                        detail = msg.getCorrelationId();
                    }
                    String response = Binding.createRestFault(msg.getRequestType(), msg.getMessage(), detail);
                    byteOut.write(response.getBytes());
                    httpResponse.setStatus(msg.getHttpStatus());
                } else {//actually try to bind response
                    final Object message = httpResponse.getMessage();
                    try {//use request binding
                        this.binding.toStream(byteOut, message, getNamespaceOverride(message, null));
                    } catch (BindingException ex) {
                        Logs.extreme().error(ex, ex);
                        byteOut.reset();
                        try {//use default binding with request namespace
                            getDefaultBinding().toStream(byteOut, message,
                                    getNamespaceOverride(message, this.namespace));
                        } catch (BindingException ex1) {//use default binding
                            byteOut.reset();
                            BindingManager.getDefaultBinding().toStream(byteOut, message);
                        }
                    } catch (Exception e) {
                        LOG.debug(e);
                        Logs.exhaust().error(e, e);
                        throw e;
                    }
                }
                byte[] req = byteOut.toByteArray();
                ChannelBuffer buffer = ChannelBuffers.wrappedBuffer(req);
                httpResponse.addHeader(HttpHeaders.Names.CONTENT_LENGTH, String.valueOf(buffer.readableBytes()));
                httpResponse.addHeader(HttpHeaders.Names.CONTENT_TYPE, "application/xml; charset=UTF-8");
                httpResponse.setContent(buffer);
            } finally {
                HoldMe.canHas.unlock();
            }
        }
    }

    public static void streamResponse(final Object message) {
        final Context context = Contexts.lookup();
        final Channel channel = context.getChannel();
        final RestfulMarshallingHandler handler = channel.getPipeline().get(RestfulMarshallingHandler.class);

        final DefaultHttpResponse httpResponse = new DefaultHttpResponse(HttpVersion.HTTP_1_1,
                HttpResponseStatus.OK);
        final EncodingWrapper wrapper = getEncodingWrapper();
        wrapper.writeHeaders(httpResponse);
        try {
            httpResponse.addHeader(HttpHeaders.Names.TRANSFER_ENCODING, HttpHeaders.Values.CHUNKED);
            httpResponse.addHeader(HttpHeaders.Names.CONTENT_TYPE, "application/xml; charset=UTF-8");
            final OutputStream outputStream = wrapper.wrapOutput(new BufferedOutputStream(new OutputStream() {
                @Override
                public void write(final int b) throws IOException {
                    write(new byte[] { (byte) b }, 0, 1);
                }

                @Override
                public void write(final byte[] b, final int off, final int len) throws IOException {
                    final ChannelFuture future = Channels.write(channel,
                            new DefaultHttpChunk(ChannelBuffers.wrappedBuffer(b, off, len)));
                    if (!future.awaitUninterruptibly().isSuccess()) {
                        throw new IOException(future.getCause());
                    }
                }

                @Override
                public void flush() throws IOException {
                }
            }));
            Channels.write(channel, httpResponse);
            handler.binding.toStream(outputStream, message);
            outputStream.close(); // the implementations used flush/complete on close
            Channels.write(channel, HttpChunk.LAST_CHUNK);
        } catch (final Exception e) {
            LOG.error("Error streaming response", e);
        }
    }

    protected String getNamespaceOverride(@Nonnull final Object message, @Nullable final String namespace) {
        return namespace;
    }

    /**
     * Get the encoding wrapper to use for the request.
     *
     * This simple check for encoding support fails if a request specifies any
     * "q" value (i.e. encoding preferences, or any other parameters or
     * extension)
     */
    static EncodingWrapper getEncodingWrapper() {
        EncodingWrapper wrapper = null;

        final MappingHttpRequest request = Contexts.lookup().getHttpRequest();
        if (request != null) {
            final String accept = Objects.firstNonNull(request.getHeader(HttpHeaders.Names.ACCEPT_ENCODING), "")
                    .toLowerCase();
            if (accept.matches("[a-z, *_-]{1,1024}")) {
                final Iterable<String> encodings = Splitter.on(",").trimResults().omitEmptyStrings().split(accept);
                if (Iterables.contains(encodings, HttpHeaders.Values.DEFLATE)) {
                    wrapper = new DeflateEncodingWrapper();
                } else if (Iterables.contains(encodings, HttpHeaders.Values.GZIP)) {
                    wrapper = new GzipEncodingWrapper();
                }
            }
        }

        if (wrapper == null) {
            wrapper = new EncodingWrapper();
        }

        return wrapper;
    }

    private static class EncodingWrapper {
        void writeHeaders(@Nonnull final HttpMessage httpResponse) {
        }

        @Nonnull
        OutputStream wrapOutput(@Nonnull final OutputStream out) throws IOException {
            return out;
        }
    }

    private static abstract class CompressingEncodingWrapper extends EncodingWrapper {
        private final String encoding;

        protected CompressingEncodingWrapper(final String encoding) {
            this.encoding = encoding;
        }

        @Override
        void writeHeaders(@Nonnull final HttpMessage httpResponse) {
            httpResponse.addHeader(HttpHeaders.Names.CONTENT_ENCODING, encoding);
        }

        @Nonnull
        @Override
        final OutputStream wrapOutput(@Nonnull final OutputStream out) throws IOException {
            return compress(out);
        }

        @Nonnull
        abstract OutputStream compress(@Nonnull OutputStream out) throws IOException;
    }

    private static final class DeflateEncodingWrapper extends CompressingEncodingWrapper {
        DeflateEncodingWrapper() {
            super(HttpHeaders.Values.DEFLATE);
        }

        @Nonnull
        @Override
        OutputStream compress(@Nonnull final OutputStream out) {
            return new DeflaterOutputStream(out);
        }
    }

    private static final class GzipEncodingWrapper extends CompressingEncodingWrapper {
        private GzipEncodingWrapper() {
            super(HttpHeaders.Values.GZIP);
        }

        @Nonnull
        @Override
        OutputStream compress(@Nonnull final OutputStream out) throws IOException {
            return new GZIPOutputStream(out);
        }
    }

    /**
     * @return the namespace
     */
    public String getNamespace() {
        return this.namespace;
    }

    /**
     * @return the binding
     */
    public Binding getBinding() {
        return this.binding;
    }

    public Binding getDefaultBinding() {
        return this.defaultBinding;
    }

}