source: MDService2/trunk/MDService2/src/eu/clarin/cmdi/mdservice/action/SRUProxyAction.java @ 1187

package eu.clarin.cmdi.mdservice.action;

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.StringWriter;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.HashMap;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.TransformerFactoryConfigurationError;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import net.sf.json.JSON;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import net.sf.json.JSONSerializer;


import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.StringEscapeUtils;
import org.apache.struts2.interceptor.ServletRequestAware;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

import com.opensymphony.xwork2.ActionSupport;

import eu.clarin.cmdi.mdservice.model.Diagnostic;
import eu.clarin.cmdi.mdservice.model.Diagnostics;


public class SRUProxyAction extends ActionSupport
implements ServletRequestAware 
{

        private static final long serialVersionUID = 1L;
        
        private Diagnostics diagnostics;
        
        /** 
         * Properties to be filled by Struts with according request-parameters
         */     
        private String q;
        private String version;
        private String operation;
        private String query;
        private int startRecord;
        private int maximumRecords;
        private String recordPacking;
        private String recordSchema;
        private String recordXPath;
        private int resultSetTTL;
        private String sortKeys;
        private String stylesheet;      
        private String x_cmd_repository;
        private String x_cmd_collections;

        private MDRepoProxyAction mdrepoproxyaction;
        private InputStream resultStream;
        private HttpServletRequest request; 
        
        private final static HashMap<String,String> hash_operations = new HashMap<String,String>();
         static
         {       
                 hash_operations.put("searchRetrieve", "recordset");
         } 
         
         public SRUProxyAction(){
                 super();
                 initialize();
         }
         
         protected void  initialize(){
                 //repository = 1;
         }
         
         @Override
                public void setServletRequest(HttpServletRequest arg0) {
                        request = arg0;
                }

                public HttpServletRequest getServletRequest() {
                        return request;
                }
                
                public Diagnostics getDiagnostics(){
                        return this.diagnostics;
                }
                
                public void setDiagnostics(Diagnostics diagnostics){
                        this.diagnostics = diagnostics;
                }
        
                
         public String getQ() {
                        return q;
                }

                public void setQ(String q) {
                        this.q = q;
                }
         
         public InputStream getResultStream() {
             return resultStream;
         }
         public void setResultStream(InputStream _resultStream){
                resultStream = _resultStream;
         }
        

        public String getVersion() {
                return version;
        }

        public void setVersion(String version) {
                this.version = version;
        }

        public String getOperation() {
                return operation;
        }

        public void setOperation(String operation) {
                this.operation = operation;
        }
        
        public String getQuery() {
                return query;
        }

        public void setQuery(String query) {
                this.query = query;
        }
        
        public int getStartRecord() {
                return startRecord;
        }

        public void setStartRecord(int startRecord) {
                this.startRecord = startRecord;
        }
        public int getMaximumRecords() {
                return maximumRecords;
        }

        public void setMaximumRecords(int maximumRecords) {
                this.maximumRecords = maximumRecords;
        }
        
        public String getRecordPacking() {
                return recordPacking;
        }

        public void setRecordPacking(String recordPacking) {
                this.recordPacking = recordPacking;
        }

        public String getRecordSchema() {
                return recordSchema;
        }

        public void setRecordSchema(String recordSchema) {
                this.recordSchema = recordSchema;
        }

        public String getRecordXPath() {
                return recordXPath;
        }

        public void setRecordXPath(String recordXPath) {
                this.recordXPath = recordXPath;
        }

        public int getResultSetTTL() {
                return resultSetTTL;
        }

        public void setResultSetTTL(int resultSetTTL) {
                this.resultSetTTL = resultSetTTL;
        }
        
        public String getSortKeys() {
                return sortKeys;
        }

        public void setSortKeys(String sortKeys) {
                this.sortKeys = sortKeys;
        }
                
        public String getStylesheet() {
                return stylesheet;
        }

        public void setStylesheet(String stylesheet) {
                this.stylesheet = stylesheet;
        }
        
        public String getX_cmd_repository(){
                return x_cmd_repository;
        }
        
        public void setX_cmd_repository(String x_cmd_repository){
                this.x_cmd_repository = x_cmd_repository;
        }

        public String getX_cmd_collections(){
                return x_cmd_collections;
        }
        
        public void setX_cmd_collections(String x_cmd_collections){
                this.x_cmd_collections = x_cmd_collections;
        }

        
        public String getDiagnosticStreamName() throws TransformerConfigurationException, UnsupportedEncodingException, ParserConfigurationException, TransformerException, TransformerFactoryConfigurationError{
                resultStream = this.Diagnostics().buildXMLStream();
                return "resultStream";
        }
        /**
         * primitive identification of the target-proxy
         * base for finding the right base_url in the props
         * subclass has to override with its specific proxykey
         * @return
         */
        public String getProxyKey() {
                return "";
        }
        
        public Diagnostics Diagnostics(){
                if (this.diagnostics == null){
                        this.diagnostics = new Diagnostics();
                }
                return this.diagnostics;
        }
        
        public void prepare(){
                // special handling of parameter setting, x-cmd-... not alowed in java
                this.setX_cmd_repository(getServletRequest().getParameter("x-cmd-repository"));
                this.setX_cmd_collections(getServletRequest().getParameter("x-cmd-collections"));

                mdrepoproxyaction = new MDRepoProxyAction();
                mdrepoproxyaction.setDiagnostics(diagnostics);
                
                //operation
                if (this.operation == null) {
                        this.Diagnostics().Add(Diagnostic.MANDATORY_NOTSUPPLIED, "operation");
                        //return -1;
                }
                if (!operation.equals("searchRetrieve")) {
                        this.Diagnostics().Add(Diagnostic.UNSUPPOERTED_OPERATION, "Only searchRetrieve supported.");
                        //return -1;
                }
                mdrepoproxyaction.setActionkey(hash_operations.get(this.getOperation()));
                //version
                if (this.version == null) {
                        this.Diagnostics().Add(Diagnostic.MANDATORY_NOTSUPPLIED, "version");
                        //return -1;
                }
                if (!version.equals("1.2")) {
                        this.Diagnostics().Add(Diagnostic.UNSUPPORTED_VERSION, "Version 1.2 supported.");
                        //return -1;
                }
                //query
                mdrepoproxyaction.setSquery("");
                if (this.query == null) {
                        this.Diagnostics().Add(Diagnostic.MANDATORY_NOTSUPPLIED, "query");
                        //return -1;
                }
                mdrepoproxyaction.setQ(getQuery());
                
                mdrepoproxyaction.setFormat("xml");
                
                if ((this.startRecord < 0 ) ||(getServletRequest().getParameter("startRecord").equals("0"))) {
                        this.Diagnostics().Add(new Diagnostic(Diagnostic.UNSUPPORTED_PARAMETERVALUE, "startRecord must by grater than 0."));//,Diagnostic.NONFATALNONSURORGATE));
                        //mdrepoproxyaction.setStartItem("1");
                } else {
                        mdrepoproxyaction.setStartItem(Integer.toString(getStartRecord()));
                }
        
                if ((this.maximumRecords < 0 ) ||(getServletRequest().getParameter("maximumRecords").equals("0"))){
                           this.Diagnostics().Add(new Diagnostic(Diagnostic.UNSUPPORTED_PARAMETERVALUE, 
                                           "maximumRecords must by grater than 0."));
                } else {
                        mdrepoproxyaction.setMaximumItems(Integer.toString(this.getMaximumRecords()));  
                }
                
                if (this.getX_cmd_repository() != null ) {
                        mdrepoproxyaction.setRepository(this.getX_cmd_repository());
                        //TODO\
                        if (mdrepoproxyaction.getBaseURI() == null) this.Diagnostics().Add(Diagnostic.UNSUPPORTED_PARAMETERVALUE, "Unknown repository." + getX_cmd_repository());
                }
                if (this.getX_cmd_collections() != null ) {
                        mdrepoproxyaction.setCollection(this.getX_cmd_collections());
                }
                
                //return 1;
        }
        public static String inputStreamAsString(InputStream stream)
                throws IOException {
                BufferedReader br = new BufferedReader(new InputStreamReader(stream));
                StringBuilder sb = new StringBuilder();
                String line = null;

                while ((line = br.readLine()) != null) {
                sb.append(line + "\n");
                }

                br.close();
                return sb.toString();
        }

         public static Document newDocumentFromInputStream(InputStream in) {
                    DocumentBuilderFactory factory = null;
                    DocumentBuilder builder = null;
                    Document ret = null;

                    try {
                      factory = DocumentBuilderFactory.newInstance();
                      builder = factory.newDocumentBuilder();
                    } catch (ParserConfigurationException e) {
                      e.printStackTrace();
                    }

                    try {
                      ret = builder.parse(new InputSource(in));
                    } catch (SAXException e) {
                      e.printStackTrace();
                    } catch (IOException e) {
                      e.printStackTrace();
                    }
                    return ret;
                  }


        public void postprocess() throws TransformerConfigurationException, UnsupportedEncodingException, ParserConfigurationException, TransformerException, TransformerFactoryConfigurationError{
                //recordPacking
                if (this.getRecordPacking() != null){
                        if (this.getRecordPacking().toLowerCase().equals("string")){
                                try {
                                        resultStream = IOUtils.toInputStream(StringEscapeUtils.escapeXml(inputStreamAsString(resultStream)));
                                } catch (IOException e) {
                                        // TODO Auto-generated catch block
                                        e.printStackTrace();
                                }

                        }
                }
                
                // add diagnostics
                if (Diagnostics().Exists()){
                        Document doc = newDocumentFromInputStream(resultStream);
                        Node r_element=  doc.getElementsByTagName("searchRetrieveResponse").item(0);
                        Document ddoc = Diagnostics().buildXMLDocument();
                        Node d_element=  ddoc.getElementsByTagName("diagnostics").item(0);
                        doc.adoptNode(d_element);
                        r_element.appendChild(d_element);
                        DOMSource source = new DOMSource(doc);   
                        StringWriter xmlAsWriter = new StringWriter();   
                        StreamResult result = new StreamResult(xmlAsWriter);    
                        TransformerFactory.newInstance().newTransformer().transform(source, result);
                        resultStream = new ByteArrayInputStream(xmlAsWriter.toString().getBytes("UTF-8"));
                }
        }
        
        /**
         * default Action method
         */
        public String execute() throws Exception {
                prepare();
                if (Diagnostics().Accepted()){
                        //TODO diagnostic
                        if (this.mdrepoproxyaction.getTargetRequest() == null) {
                                Diagnostics().Add(Diagnostic.QUERYSYNTAXERROR);
                                return ERROR;
                        }
                        if (this.mdrepoproxyaction.execute() == SUCCESS){
                                resultStream = this.mdrepoproxyaction.getResultStream();
                                postprocess();
                                return SUCCESS;
                        }
                }
                return ERROR;
        }


}