001package ca.uhn.fhir.rest.client.apache;
002
003/*
004 * #%L
005 * HAPI FHIR - Core Library
006 * %%
007 * Copyright (C) 2014 - 2017 University Health Network
008 * %%
009 * Licensed under the Apache License, Version 2.0 (the "License");
010 * you may not use this file except in compliance with the License.
011 * You may obtain a copy of the License at
012 * 
013 *      http://www.apache.org/licenses/LICENSE-2.0
014 * 
015 * Unless required by applicable law or agreed to in writing, software
016 * distributed under the License is distributed on an "AS IS" BASIS,
017 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
018 * See the License for the specific language governing permissions and
019 * limitations under the License.
020 * #L%
021 */
022
023import java.io.ByteArrayOutputStream;
024import java.io.IOException;
025import java.util.zip.GZIPOutputStream;
026
027import org.apache.http.Header;
028import org.apache.http.HttpEntityEnclosingRequest;
029import org.apache.http.client.methods.HttpRequestBase;
030import org.apache.http.entity.ByteArrayEntity;
031
032import ca.uhn.fhir.rest.client.IClientInterceptor;
033import ca.uhn.fhir.rest.client.api.IHttpRequest;
034import ca.uhn.fhir.rest.client.api.IHttpResponse;
035import ca.uhn.fhir.rest.server.Constants;
036
037/**
038 * Client interceptor which GZip compresses outgoing (POST/PUT) contents being uploaded
039 * from the client to the server. This can improve performance by reducing network 
040 * load time.
041 */
042public class GZipContentInterceptor implements IClientInterceptor {
043        private static final org.slf4j.Logger ourLog = org.slf4j.LoggerFactory.getLogger(GZipContentInterceptor.class);
044        
045        @Override
046        public void interceptRequest(IHttpRequest theRequestInterface) {
047                HttpRequestBase theRequest = ((ApacheHttpRequest) theRequestInterface).getApacheRequest();
048                if (theRequest instanceof HttpEntityEnclosingRequest) {
049                        Header[] encodingHeaders = theRequest.getHeaders(Constants.HEADER_CONTENT_ENCODING);
050                        if (encodingHeaders == null || encodingHeaders.length == 0) {
051                                HttpEntityEnclosingRequest req = (HttpEntityEnclosingRequest)theRequest;
052                                
053                                ByteArrayOutputStream bos = new ByteArrayOutputStream();
054                                GZIPOutputStream gos;
055                                try {
056                                        gos = new GZIPOutputStream(bos);
057                                        req.getEntity().writeTo(gos);
058                                        gos.finish();
059                                } catch (IOException e) {
060                                        ourLog.warn("Failed to GZip outgoing content", e);
061                                        return;
062                                }
063                                
064                                byte[] byteArray = bos.toByteArray();
065                                ByteArrayEntity newEntity = new ByteArrayEntity(byteArray);
066                                req.setEntity(newEntity);
067                                req.addHeader(Constants.HEADER_CONTENT_ENCODING, "gzip");
068                        }
069                }
070                
071        }
072
073        @Override
074        public void interceptResponse(IHttpResponse theResponse) throws IOException {
075                // nothing
076        }
077
078}