/*
* 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.jena.web ;
import java.io.IOException ;
import java.io.OutputStream ;
import org.apache.http.HttpEntity ;
import org.apache.http.client.methods.HttpHead ;
import org.apache.http.client.methods.HttpUriRequest ;
import org.apache.http.entity.ContentProducer ;
import org.apache.http.entity.EntityTemplate ;
import org.apache.jena.atlas.web.HttpException ;
import org.apache.jena.atlas.web.auth.HttpAuthenticator ;
import org.apache.jena.atlas.web.auth.SimpleAuthenticator ;
import org.apache.jena.riot.RDFDataMgr ;
import org.apache.jena.riot.RDFFormat ;
import org.apache.jena.riot.WebContent ;
import org.apache.jena.riot.system.IRILib ;
import org.apache.jena.riot.web.* ;
import com.hp.hpl.jena.graph.Graph ;
import com.hp.hpl.jena.graph.Node ;
import com.hp.hpl.jena.shared.JenaException ;
/**
* A dataset graph accessor that talks to stores that implement the SPARQL 1.1
* Graph Store Protocol
*/
public class DatasetGraphAccessorHTTP implements DatasetGraphAccessor {
// Test for this class are in Fuseki so they can be run with a server.
private final String remote ;
private static final HttpResponseHandler noResponse = HttpResponseLib.nullResponse ;
private HttpAuthenticator authenticator ;
/** Format used to send a graph to the server */
private static RDFFormat defaultSendLang = RDFFormat.RDFXML_PLAIN ;
/**
* Create a DatasetUpdater for the remote URL
*
* @param remote
* Remote URL
*/
public DatasetGraphAccessorHTTP(String remote) {
this.remote = remote ;
}
/**
* Create a DatasetUpdater for the remote URL
*
* @param remote
* Remote URL
* @param authenticator
* HTTP Authenticator
*/
public DatasetGraphAccessorHTTP(String remote, HttpAuthenticator authenticator) {
this(remote) ;
this.setAuthenticator(authenticator) ;
}
/**
* Sets authentication credentials for the remote URL
*
* @param username
* User name
* @param password
* Password
*/
public void setAuthentication(String username, char[] password) {
this.setAuthenticator(new SimpleAuthenticator(username, password)) ;
}
/**
* Sets an authenticator to use for authentication to the remote URL
*
* @param authenticator
* Authenticator
*/
public void setAuthenticator(HttpAuthenticator authenticator) {
this.authenticator = authenticator ;
}
@Override
public Graph httpGet() {
return doGet(targetDefault()) ;
}
@Override
public Graph httpGet(Node graphName) {
return doGet(target(graphName)) ;
}
/**
* Accept header for fetching graphs - prefer N-triples
*
* @See WebContent.defaultGraphAcceptHeader
*
*/
private static String GetAcceptHeader = "application/n-triples,text/turtle;q=0.9,application/rdf+xml;q=0.8,application/xml;q=0.7" ;
protected Graph doGet(String url) {
HttpCaptureResponse<Graph> graph = HttpResponseLib.graphHandler() ;
try {
HttpOp.execHttpGet(url, GetAcceptHeader, graph, this.authenticator) ;
} catch (HttpException ex) {
if ( ex.getResponseCode() == HttpSC.NOT_FOUND_404 )
return null ;
throw ex ;
}
return graph.get() ;
}
@Override
public boolean httpHead() {
return doHead(targetDefault()) ;
}
@Override
public boolean httpHead(Node graphName) {
return doHead(target(graphName)) ;
}
protected boolean doHead(String url) {
HttpUriRequest httpHead = new HttpHead(url) ;
try {
HttpOp.execHttpHead(url, WebContent.defaultGraphAcceptHeader, noResponse, null, null, this.authenticator) ;
return true ;
} catch (HttpException ex) {
if ( ex.getResponseCode() == HttpSC.NOT_FOUND_404 )
return false ;
throw ex ;
}
}
@Override
public void httpPut(Graph data) {
doPut(targetDefault(), data) ;
}
@Override
public void httpPut(Node graphName, Graph data) {
doPut(target(graphName), data) ;
}
protected void doPut(String url, Graph data) {
HttpEntity entity = graphToHttpEntity(data) ;
HttpOp.execHttpPut(url, entity, null, null, this.authenticator) ;
}
@Override
public void httpDelete() {
doDelete(targetDefault()) ;
}
@Override
public void httpDelete(Node graphName) {
doDelete(target(graphName)) ;
}
protected void doDelete(String url) {
try {
HttpOp.execHttpDelete(url, noResponse, null, null, this.authenticator) ;
} catch (HttpException ex) {
if ( ex.getResponseCode() == HttpSC.NOT_FOUND_404 )
return ;
}
}
@Override
public void httpPost(Graph data) {
doPost(targetDefault(), data) ;
}
@Override
public void httpPost(Node graphName, Graph data) {
doPost(target(graphName), data) ;
}
protected void doPost(String url, Graph data) {
HttpEntity entity = graphToHttpEntity(data) ;
HttpOp.execHttpPost(url, entity, null, null, this.authenticator) ;
}
@Override
public void httpPatch(Graph data) {
throw new UnsupportedOperationException() ;
}
@Override
public void httpPatch(Node graphName, Graph data) {
throw new UnsupportedOperationException() ;
}
protected final String targetDefault() {
return remote + "?" + HttpNames.paramGraphDefault + "=" ;
}
protected final String target(Node name) {
if ( !name.isURI() )
throw new JenaException("Not a URI: " + name) ;
String guri = name.getURI() ;
// Encode
guri = IRILib.encodeUriComponent(guri) ;
return remote + "?" + HttpNames.paramGraph + "=" + guri ;
}
/**
* RDF syntax to use when sending graphs with POST and PUT
*/
protected RDFFormat getOutboundSyntax() { return defaultSendLang ; }
/** Create an HttpEntity for the graph */
protected HttpEntity graphToHttpEntity(final Graph graph) {
final RDFFormat syntax = getOutboundSyntax() ;
ContentProducer producer = new ContentProducer() {
@Override
public void writeTo(OutputStream out) throws IOException {
RDFDataMgr.write(out, graph, syntax) ;
}
} ;
EntityTemplate entity = new EntityTemplate(producer) ;
String ct = syntax.getLang().getContentType().getContentType() ;
entity.setContentType(ct) ;
return entity ;
}
}