Java tutorial
/* * eXist Open Source Native XML Database * Copyright (C) 2007-2009 The eXist Project * http://exist-db.org * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * 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 Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * $Id$ */ package org.exist.xquery.modules.httpclient; import org.apache.commons.httpclient.methods.ByteArrayRequestEntity; import org.apache.commons.httpclient.methods.PostMethod; import org.apache.commons.httpclient.methods.RequestEntity; import org.apache.commons.httpclient.methods.StringRequestEntity; import org.apache.commons.httpclient.methods.multipart.FilePart; import org.apache.commons.httpclient.methods.multipart.MultipartRequestEntity; import org.apache.commons.httpclient.methods.multipart.Part; import org.apache.commons.httpclient.methods.multipart.StringPart; import org.apache.log4j.Logger; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.exist.dom.QName; import org.apache.commons.io.output.ByteArrayOutputStream; import org.exist.util.serializer.SAXSerializer; import org.exist.xquery.FunctionSignature; import org.exist.xquery.XPathException; import org.exist.xquery.XQueryContext; import org.exist.xquery.value.Item; import org.exist.xquery.value.NodeValue; import org.exist.xquery.value.Sequence; import org.exist.xquery.value.SequenceType; import org.exist.xquery.value.Type; import java.io.File; import java.io.FileNotFoundException; import java.io.IOException; import java.io.OutputStreamWriter; import java.io.UnsupportedEncodingException; import java.util.Properties; /** * Performs HTTP Post method * * @author Adam Retter <adam@exist-db.org> * @author Andrzej Taramina <andrzej@chaeron.com> * @author <a href="mailto:shabanovd@gmail.com">Dmitriy Shabanov</a> * @version 1.3 * @serial 20100228 */ public class POSTFunction extends BaseHTTPClientFunction { protected static final Logger logger = Logger.getLogger(POSTFunction.class); public final static FunctionSignature[] signatures = { new FunctionSignature(new QName("post", NAMESPACE_URI, PREFIX), "Performs a HTTP POST request." + " This method returns the HTTP response encoded as an XML fragment, that looks as follows: <httpclient:response xmlns:httpclient=\"http://exist-db.org/xquery/httpclient\" statusCode=\"200\"><httpclient:headers><httpclient:header name=\"name\" value=\"value\"/>...</httpclient:headers><httpclient:body type=\"xml|xhtml|text|binary\" mimetype=\"returned content mimetype\">body content</httpclient:body></httpclient:response>" + " where XML body content will be returned as a Node, HTML body content will be tidied into an XML compatible form, a body with mime-type of \"text/...\" will be returned as a URLEncoded string, and any other body content will be returned as xs:base64Binary encoded data.", new SequenceType[] { URI_PARAM, POST_CONTENT_PARAM, PERSIST_PARAM, REQUEST_HEADER_PARAM }, XML_BODY_RETURN), new FunctionSignature(new QName("post-form", NAMESPACE_URI, PREFIX), "Performs a HTTP POST request for a form." + " This method returns the HTTP response encoded as an XML fragment, that looks as follows: <httpclient:response xmlns:httpclient=\"http://exist-db.org/xquery/httpclient\" statusCode=\"200\"><httpclient:headers><httpclient:header name=\"name\" value=\"value\"/>...</httpclient:headers><httpclient:body type=\"xml|xhtml|text|binary\" mimetype=\"returned content mimetype\">body content</httpclient:body></httpclient:response>" + " where XML body content will be returned as a Node, HTML body content will be tidied into an XML compatible form, a body with mime-type of \"text/...\" will be returned as a URLEncoded string, and any other body content will be returned as xs:base64Binary encoded data.", new SequenceType[] { URI_PARAM, POST_FORM_PARAM, PERSIST_PARAM, REQUEST_HEADER_PARAM }, XML_BODY_RETURN) }; public POSTFunction(XQueryContext context, FunctionSignature signature) { super(context, signature); } public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException { Sequence response = null; // must be a URL if (args[0].isEmpty()) { return (Sequence.EMPTY_SEQUENCE); } //get the url String url = args[0].itemAt(0).getStringValue(); //get the payload Item payload = args[1].itemAt(0); //get the persist state boolean persistState = args[2].effectiveBooleanValue(); PostMethod post = new PostMethod(url); if (isCalledAs("post")) { RequestEntity entity = null; if (Type.subTypeOf(payload.getType(), Type.NODE)) { //serialize the node to SAX ByteArrayOutputStream baos = new ByteArrayOutputStream(); OutputStreamWriter osw = null; try { osw = new OutputStreamWriter(baos, "UTF-8"); } catch (UnsupportedEncodingException e) { throw (new XPathException(this, e.getMessage())); } SAXSerializer sax = new SAXSerializer(osw, new Properties()); try { payload.toSAX(context.getBroker(), sax, new Properties()); osw.flush(); osw.close(); } catch (Exception e) { throw (new XPathException(this, e.getMessage())); } byte[] reqPayload = baos.toByteArray(); entity = new ByteArrayRequestEntity(reqPayload, "application/xml; charset=utf-8"); } else { try { entity = new StringRequestEntity(payload.getStringValue(), "text/text; charset=utf-8", "UTF-8"); } catch (UnsupportedEncodingException uee) { uee.printStackTrace(); } } post.setRequestEntity(entity); } else if (isCalledAs("post-form")) { Node nPayload = ((NodeValue) payload).getNode(); if ((nPayload instanceof Element) && nPayload.getNamespaceURI().equals(HTTPClientModule.NAMESPACE_URI) && nPayload.getLocalName().equals("fields")) { Part[] parts = parseFields((Element) nPayload); post.setRequestEntity(new MultipartRequestEntity(parts, post.getParams())); } else { throw (new XPathException(this, "fields must be provided")); } } else { return (Sequence.EMPTY_SEQUENCE); } //setup POST Request Headers if (!args[3].isEmpty()) { setHeaders(post, ((NodeValue) args[3].itemAt(0)).getNode()); } try { //execute the request response = doRequest(context, post, persistState, null, null); } catch (IOException ioe) { throw (new XPathException(this, ioe.getMessage(), ioe)); } finally { post.releaseConnection(); } return (response); } private Part[] parseFields(Element fields) throws XPathException { NodeList nlField = fields.getElementsByTagNameNS(HTTPClientModule.NAMESPACE_URI, "field"); Part[] parts = new Part[nlField.getLength()]; for (int i = 0; i < nlField.getLength(); i++) { Element field = (Element) nlField.item(i); if (field.hasAttribute("type") && field.getAttribute("type").equals("file")) { try { String url = field.getAttribute("value"); if (url.startsWith("xmldb:exist://")) { parts[i] = new FilePart(field.getAttribute("name"), new DBFile(url.substring(13))); } else { parts[i] = new FilePart(field.getAttribute("name"), new File(url)); } } catch (FileNotFoundException e) { throw (new XPathException(e)); } } else { parts[i] = new StringPart(field.getAttribute("name"), field.getAttribute("value")); } } return (parts); } }