source: MDService2/trunk/MDService2/src/eu/clarin/cmdi/mdservice/action/GenericProxyAction.java @ 713

package eu.clarin.cmdi.mdservice.action;

import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;

import javax.servlet.http.HttpServletRequest;
import org.apache.struts2.interceptor.ServletRequestAware;

import com.opensymphony.xwork2.ActionSupport;

/**
 * main Struts 2 controller 
 * responds to requests (collections, model, recordset) 
 * by dispatching the requests to appropriate internal methods and filling the inputStream with the result
 *  
 * @author vronk
 *
 */
public class GenericProxyAction extends ActionSupport 
implements ServletRequestAware 
{

        private static final long serialVersionUID = 1L;
        
        /** 
         * Properties to be filled by Struts with according request-parameters
         */     
        private String actionkey;
        private String q;
        private String cache = Cache.USE;
        private String collection;
        private String columns;
        private String startRecord;
        private String maximumRecords;
        private int maxdepth;
        private String format;
        private String userMsg;
        //private Map<String,Object> session;
         private HttpServletRequest request; 

        public String getQ() {
                return q;
        }

        public void setQ(String q) {
                this.q = q;
        }

        public String getCache() {
                return cache;
        }

        public void setCache(String cache) {
                this.cache = cache;
        }

        public String getCollection() {
                return collection;
        }

        public void setCollection(String collection) {
                this.collection = collection;
        }
        
        //TODO defaults
        public String getColumns() {
                String cols = columns;
                /*if (columns == null){
                        cols = "Id,Name,Title";
                }
                */
                return cols;
        }

        public void setColumns(String columns) {
                this.columns = columns;
        }
        
        public int getMaxdepth() {
                return maxdepth;
        }

        public void setMaxdepth(int maxdepth) {
                this.maxdepth = maxdepth;
        }

        public String getFormat() {
                return format;
        }

        public void setFormat(String format) {
                this.format = format;
        }
        
        public String getActionkey() {
                return actionkey;
        }

        public void setActionkey(String actionKey) {
                actionkey = actionKey;
        }
        
        public String getStartRecord() {
                return startRecord;
        }

        public void setStartRecord(String startRecord) {
                this.startRecord = startRecord;
        }

        public String getMaximumRecords() {
                return maximumRecords;
        }

        public void setMaximumRecords(String maximumRecords) {
                this.maximumRecords = maximumRecords;
        }
        
        public String getFullFormat() {         
                return actionkey + "2" + format;
        }

        /**
         * 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 String getUserMsg() {
                return userMsg;
        }

        public void setUserMsg(String userMsg) {
                this.userMsg = this.userMsg + "\n" + userMsg;
        }
        
        @Override
        public void setServletRequest(HttpServletRequest arg0) {
                request = arg0;
        }

        public HttpServletRequest getServletRequest() {
                return request;
        }


        private InputStream resultStream;
        private InputStream sourceStream;

        /**
         * The stream holding the resulting data to be sent back to the user as response
         * @return
         */
        public InputStream getResultStream() {
                return resultStream;
    }
        public void setResultStream(InputStream _resultStream){
                resultStream = _resultStream;
        }
        public void setSourceStream(InputStream _sourceStream){
                sourceStream = _sourceStream;
        }
        
        /*
        public InputStream getSourceStream() throws IOException {
                return getTargetRequest().openStream();
    }
*/
        
        private URL base_url ;
        
        public URL getBaseURL() throws MalformedURLException {          
                if (base_url == null) {
                        base_url = new URL(Admin.getConfig().getProperty(getProxyKey() + ".uri"));
                }
                return base_url;
        }
        
        
        public URL getTargetRequest() throws IOException {
        // URL targetURL =new URL( base_url, compname + ".xml");
                URL targetURL = getBaseURL();      
                      
        return targetURL;
        }
        
        public String getRequestKey() {
                String key="";
                if (getActionkey()!=null) {
                        key += getActionkey() + "//-" ;
                }
                if (getQ()!=null) {
                        key += getQ() + "//-" ;
                }
                if (getCollection()!=null) {
                        key += getCollection();
                }
                 
                return key;
        }

        public InputStream getSourceStream() throws IOException {               
                return getTargetRequest().openStream();
                //      Admin.notifyUser(getProxyKey() + ".getSourceStream() - unable to open stream: " + getTargetRequest();  
        }
        
        
        public void prepare() throws Exception {                
                
                Admin.notifyUser(getProxyKey() + ".targetURL: " + getTargetRequest() + " .format:" + getFullFormat());
                
                // Caching
                String xcid;
                Admin.notifyUser("GPA.prepareSourceStream");
                if (getCache().equals(Cache.SKIP)) {
                        
                        sourceStream = getSourceStream();
                        
                } else { 
                        if (getCache().equals(Cache.USE)) {
                                        sourceStream = Cache.getCache().getFromCache(getRequestKey());
                        }
                        if (sourceStream == null) { // either not in cache or cache_flag=refresh
                                //sourceStream = getTargetRequest().openStream();
                                sourceStream = getSourceStream();
                                xcid = Cache.getCache().putInCache(getRequestKey(),sourceStream);                       
                                Admin.notifyUser("putting in cache: " + getRequestKey());                       
                                sourceStream = Cache.getCache().getFromCache(getRequestKey());
                        }  else {
                                Admin.notifyUser("reading from cache: " + getRequestKey());
                        }
                }
                        
                if (format.equals("xml")) {                     
                        resultStream = sourceStream;    
                }else {
                        // set URL as srcFile (for MDTransformer to pass to xsl-scripts) 
                        MDTransformer.getMDTransformer().setSrcFile(getTargetRequest());
                        // getColumns
                        resultStream = MDTransformer.getMDTransformer().transformXML(sourceStream, getFullFormat(), getColumns(), getStartRecord(), getMaximumRecords());
                }
                        
                Admin.notifyUser(getProxyKey() + " success:" + (resultStream!=null));
        }

        /**
         * default Action method
         */
        public String execute() throws Exception {
//              HttpServletRequest request = ServletActionContext.getRequest();

                
                Admin.notifyUser("session-attrs:");
      Admin.notifyUser(getServletRequest().getRemoteUser() );
        //Admin.notifyUser(String.valueOf(getSession()));
      
                prepare();
                if (resultStream == null) {
                        return ERROR;   
                } else {
                        return SUCCESS;
                }               
        }


}