Java tutorial
/* * Copyright (c) 2015 Data Harmonisation Panel * * All rights reserved. This program and the accompanying materials are made * available under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation, either version 3 of the License, * or (at your option) any later version. * * You should have received a copy of the GNU Lesser General Public License * along with this distribution. If not, see <http://www.gnu.org/licenses/>. * * Contributors: * Data Harmonisation Panel <http://www.dhpanel.eu> */ package eu.esdihumboldt.hale.io.wfs; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.PipedInputStream; import java.io.PipedOutputStream; import java.net.Proxy; import java.net.URI; import java.nio.charset.StandardCharsets; import java.text.MessageFormat; import java.util.concurrent.Callable; import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import javax.xml.xpath.XPath; import javax.xml.xpath.XPathExpressionException; import javax.xml.xpath.XPathFactory; import org.apache.http.HttpEntity; import org.apache.http.HttpHost; import org.apache.http.HttpResponse; import org.apache.http.auth.AuthScope; import org.apache.http.auth.Credentials; import org.apache.http.client.fluent.Executor; import org.apache.http.client.fluent.Request; import org.apache.http.client.fluent.Response; import org.apache.http.entity.ContentType; import org.apache.http.util.EntityUtils; import org.w3c.dom.Document; import org.xml.sax.SAXException; import de.fhg.igd.slf4jplus.ALogger; import de.fhg.igd.slf4jplus.ALoggerFactory; import eu.esdihumboldt.hale.common.core.io.IOProviderConfigurationException; import eu.esdihumboldt.hale.common.core.io.ProgressIndicator; import eu.esdihumboldt.hale.common.core.io.Value; import eu.esdihumboldt.hale.common.core.io.config.UserPasswordCredentials; import eu.esdihumboldt.hale.common.core.io.impl.SubtaskProgressIndicator; import eu.esdihumboldt.hale.common.core.io.report.IOReport; import eu.esdihumboldt.hale.common.core.io.report.IOReporter; import eu.esdihumboldt.hale.common.core.io.report.impl.IOMessageImpl; import eu.esdihumboldt.hale.common.core.io.supplier.LocatableOutputSupplier; import eu.esdihumboldt.hale.common.instance.io.util.GeoInstanceWriterDecorator; import eu.esdihumboldt.hale.io.gml.writer.XmlWrapper; import eu.esdihumboldt.hale.io.gml.writer.internal.StreamGmlWriter; import eu.esdihumboldt.util.http.ProxyUtil; import eu.esdihumboldt.util.http.client.ClientProxyUtil; import eu.esdihumboldt.util.http.client.fluent.FluentProxyUtil; /** * Base class for WFS writers that directly write to the WFS-T. * * @param <T> the XML/GML writer type * @author Simon Templer */ @SuppressWarnings("restriction") public abstract class AbstractWFSWriter<T extends StreamGmlWriter> extends GeoInstanceWriterDecorator<T> implements WFSWriter, WFSConstants, UserPasswordCredentials { private static final ALogger log = ALoggerFactory.getLogger(AbstractWFSWriter.class); private LocatableOutputSupplier<? extends OutputStream> targetWfs; private OutputStream currentExecuteStream; private final LocatableOutputSupplier<? extends OutputStream> decorateeTarget = new LocatableOutputSupplier<OutputStream>() { @Override public OutputStream getOutput() throws IOException { return currentExecuteStream; } @Override public URI getLocation() { return targetWfs.getLocation(); } }; /** * @param internalProvider the internal provider producing GML */ public AbstractWFSWriter(T internalProvider) { super(internalProvider); } @Override public void setWFSVersion(WFSVersion version) { setParameter(PARAM_WFS_VERSION, Value.of(version.versionString)); } @Override public WFSVersion getWFSVersion() { String versionString = getParameter(PARAM_WFS_VERSION).as(String.class); if (versionString == null) { return null; } else return WFSVersion.fromString(versionString, null); } @Override public void setTarget(LocatableOutputSupplier<? extends OutputStream> target) { targetWfs = target; if (targetWfs == null) { super.setTarget(null); } else { super.setTarget(decorateeTarget); } } @Override public LocatableOutputSupplier<? extends OutputStream> getTarget() { return targetWfs; } @Override public IOReport execute(ProgressIndicator progress) throws IOProviderConfigurationException, IOException { progress.begin("WFS Transaction", ProgressIndicator.UNKNOWN); // configure internal provider internalProvider.setDocumentWrapper(createTransaction()); final PipedInputStream pIn = new PipedInputStream(); PipedOutputStream pOut = new PipedOutputStream(pIn); currentExecuteStream = pOut; Future<Response> futureResponse = null; IOReporter reporter = createReporter(); ExecutorService executor = Executors.newSingleThreadExecutor(); try { // read the stream (in another thread) futureResponse = executor.submit(new Callable<Response>() { @Override public Response call() throws Exception { Proxy proxy = ProxyUtil.findProxy(targetWfs.getLocation()); Request request = Request.Post(targetWfs.getLocation()).bodyStream(pIn, ContentType.APPLICATION_XML); Executor executor = FluentProxyUtil.setProxy(request, proxy); // authentication String user = getParameter(PARAM_USER).as(String.class); String password = getParameter(PARAM_PASSWORD).as(String.class); if (user != null) { // target host int port = targetWfs.getLocation().getPort(); String hostName = targetWfs.getLocation().getHost(); String scheme = targetWfs.getLocation().getScheme(); HttpHost host = new HttpHost(hostName, port, scheme); // add credentials Credentials cred = ClientProxyUtil.createCredentials(user, password); executor.auth(new AuthScope(host), cred); executor.authPreemptive(host); } try { return executor.execute(request); } finally { pIn.close(); } } }); // write the stream SubtaskProgressIndicator subprogress = new SubtaskProgressIndicator(progress); reporter = (IOReporter) super.execute(subprogress); } finally { executor.shutdown(); } try { Response response = futureResponse.get(); HttpResponse res = response.returnResponse(); int statusCode = res.getStatusLine().getStatusCode(); XPathFactory xPathfactory = XPathFactory.newInstance(); XPath xpath = xPathfactory.newXPath(); if (statusCode >= 200 && statusCode < 300) { // success reporter.setSuccess(reporter.isSuccess()); // construct summary from response try { Document responseDoc = parseResponse(res.getEntity()); // totalInserted String inserted = xpath.compile("//TransactionSummary/totalInserted").evaluate(responseDoc); // XXX totalUpdated // XXX totalReplaced // XXX totalDeleted reporter.setSummary("Inserted " + inserted + " features."); } catch (XPathExpressionException e) { log.error("Error in XPath used to evaluate service response"); } catch (ParserConfigurationException | SAXException e) { reporter.error(new IOMessageImpl(MessageFormat.format( "Server returned status code {0}, but could not parse server response", statusCode), e)); reporter.setSuccess(false); } } else { // failure reporter.error( new IOMessageImpl("Server reported failure with code " + res.getStatusLine().getStatusCode() + ": " + res.getStatusLine().getReasonPhrase(), null)); reporter.setSuccess(false); try { Document responseDoc = parseResponse(res.getEntity()); String errorText = xpath.compile("//ExceptionText/text()").evaluate(responseDoc); reporter.setSummary("Request failed: " + errorText); } catch (XPathExpressionException e) { log.error("Error in XPath used to evaluate service response"); } catch (ParserConfigurationException | SAXException e) { reporter.error(new IOMessageImpl("Could not parse server response", e)); reporter.setSuccess(false); } } } catch (ExecutionException | InterruptedException e) { reporter.error(new IOMessageImpl("Failed to execute WFS-T request", e)); reporter.setSuccess(false); } progress.end(); return reporter; } private Document parseResponse(HttpEntity entity) throws IOException, ParserConfigurationException, SAXException { DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); DocumentBuilder builder = factory.newDocumentBuilder(); byte[] data = EntityUtils.toByteArray(entity); try (InputStream response = new ByteArrayInputStream(data)) { return builder.parse(response); } catch (SAXException e) { String response = new String(data, StandardCharsets.UTF_8); throw new SAXException("Invalid XML response: " + response, e); } } /** * @return the transaction wrapper */ protected abstract XmlWrapper createTransaction(); }