Commit emails of the iDok project

["AFS account Roman Geus" <geus AT savannah.psi.ch>]

Author: geus
Date: Tue Aug 26 17:36:47 2008
New Revision: 191

Log:
Added draft of client side search service for REST

Added:
   branches/rest/java/ch/idok/service/client/search/rest/RestQueryMatch.java
   
branches/rest/java/ch/idok/service/client/search/rest/RestSearchIterator.java
   
branches/rest/java/ch/idok/service/client/search/rest/RestSearchService.java

Added: 
branches/rest/java/ch/idok/service/client/search/rest/RestQueryMatch.java
==============================================================================
--- (empty file)
+++ branches/rest/java/ch/idok/service/client/search/rest/RestQueryMatch.java 
  Tue Aug 26 17:36:47 2008
@@ -0,0 +1,64 @@
+package ch.idok.service.client.search.rest;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.w3c.dom.Node;
+
+import ch.idok.common.util.Base64Coder;
+import ch.idok.service.common.search.QueryMatch;
+
+public class RestQueryMatch implements QueryMatch {
+
+    private String id = null;
+    private String env = null;
+    private byte[] content = null;
+    private Map<String, String> meta = null;
+    private String rev = null;
+    private String repo = null;
+
+    public RestQueryMatch(Node node) {
+        for (Node n = node.getFirstChild(); n != null; n = 
n.getNextSibling()) {
+            if (n.getNodeName().equals("Id"))
+                id = n.getTextContent();
+            else if (n.getNodeName().equals("Environment"))
+                env = n.getTextContent();
+            else if (n.getNodeName().equals("Content"))
+                content = 
Base64Coder.decode(n.getTextContent().toCharArray());
+            else if (n.getNodeName().equals("Meta")) {
+                meta = new HashMap<String, String>();
+                for (Node e = n.getFirstChild(); e != null; e = 
e.getNextSibling()) {
+                    meta.put(e.getFirstChild().getTextContent(), 
e.getLastChild().getTextContent());
+                }
+            } else if (n.getNodeName().equals("Rev"))
+                rev = n.getTextContent();                
+            else if (n.getNodeName().equals("Repo"))
+                repo = n.getTextContent();
+        }        
+    }
+
+    public byte[] getContent() {
+        return content;
+    }
+
+    public String getEnvironment() {
+        return env;
+    }
+
+    public String getId() {
+        return id; 
+    }
+
+    public Map<String, String> getMetadata() {
+        return meta;
+    }
+
+    public String getRepo() {
+        return repo;
+    }
+
+    public String getVersion() {
+        return rev;
+    }
+
+}

Added: 
branches/rest/java/ch/idok/service/client/search/rest/RestSearchIterator.java
==============================================================================
--- (empty file)
+++ 
branches/rest/java/ch/idok/service/client/search/rest/RestSearchIterator.java 
      Tue Aug 26 17:36:47 2008
@@ -0,0 +1,299 @@
+package ch.idok.service.client.search.rest;
+
+import java.util.NoSuchElementException;
+import java.util.logging.Logger;
+
+import javax.security.auth.Subject;
+import javax.ws.rs.core.UriBuilder;
+
+import org.restlet.Client;
+import org.restlet.Context;
+import org.restlet.data.ChallengeResponse;
+import org.restlet.data.ChallengeScheme;
+import org.restlet.data.Method;
+import org.restlet.data.Protocol;
+import org.restlet.data.Request;
+import org.restlet.data.Response;
+import org.restlet.data.Status;
+import org.restlet.resource.DomRepresentation;
+import org.restlet.util.NodeSet;
+import org.w3c.dom.Node;
+
+import ch.idok.common.errorhandling.DmsException;
+import ch.idok.common.errorhandling.ErrorType;
+import ch.idok.common.util.AuthUtil;
+import ch.idok.common.util.DmsCredentials;
+import ch.idok.common.util.ServiceTokenAction;
+import ch.idok.service.client.rest.RestClientProvider;
+import ch.idok.service.common.Iterator;
+import ch.idok.service.common.search.QueryMatch;
+import ch.idok.service.common.search.SearchService;
+import ch.idok.service.server.rest.NegotiateFilter;
+
+/**
+ * Iterator<QueryMatch> that returns search hits obtained through the REST
+ * search interface
+ */
+public class RestSearchIterator implements Iterator<QueryMatch> {
+
+    private final int hitsPerBatch = 10;
+
+    private final RestClientProvider restClientProvider;
+
+    private final Logger logger;
+
+    private final DmsCredentials cred;
+
+    private final String query;
+
+    private final String fields;
+
+    private final long resultType;
+
+    private final Client client;
+
+    /**
+     * The next element to be returned by <code>next()</code> or
+     * <code>nextElement()</code>, null if no further elements exist
+     */
+    private RestQueryMatch nextElement;
+
+    private java.util.Iterator<Node> hits;
+
+    /**
+     * Number of already consumed search hits, i.e. number of
+     * <code>next()</code> or <code>nextElement()</code> calls
+     */
+    int index;
+
+    /**
+     * True if all search hits have been fetched from the REST service
+     */
+    private boolean lastBatch;
+
+    /**
+     * RestSearchIterator constructor
+     */
+    RestSearchIterator(Logger logger, RestClientProvider restClientProvider,
+            DmsCredentials cred, String query, String fields, long 
resultType)
+            throws DmsException {
+        this.logger = logger;
+        this.restClientProvider = restClientProvider;
+        this.cred = cred;
+        this.query = query;
+        this.fields = fields;
+        this.resultType = resultType;
+        index = 0;
+        lastBatch = false;
+
+        // Restlet context
+        final Context context = new Context(logger);
+
+        // HTTP client connector to handle the REST call
+        client = new Client(context, Protocol.HTTP);
+
+        // Fetch first batch of search hits
+        fetch();
+    }
+
+    /**
+     * Build the URI for the REST call
+     */
+    private String buildRestSearchURI(String query, String fields,
+            long resultType, int start, int num) throws DmsException {
+        // parse query string
+        String project;
+        String repository;
+        String q;
+        int iColon = query.indexOf("::");
+        int iSlash = query.indexOf('/');
+        if (iSlash < iColon) {
+            project = query.substring(0, iSlash);
+            repository = query.substring(iSlash + 1, iColon);
+            q = query.substring(iColon + 2);
+        } else {
+            throw new DmsException(ErrorType.BAD_ARG, this,
+                    "Could not parse query string \"" + query + "\"", "");
+        }
+
+        // Build request URI
+        StringBuilder sb = new StringBuilder();
+        if ((resultType & SearchService.METADATA) != 0)
+            sb.append("meta,");
+        if ((resultType & SearchService.MATCH_ENVIRONEMENT) != 0)
+            sb.append("env,");
+        if ((resultType & SearchService.DOC_CONTENT) != 0)
+            sb.append("doc,");
+        if (sb.length() > 0)
+            sb.deleteCharAt(sb.length() - 1);
+        String outputfields = sb.toString();
+
+        UriBuilder ub = UriBuilder.fromUri(restClientProvider.getBaseUri())
+                
.path("search").path(project).path(repository).queryParam("q",
+                        q).queryParam("start", Integer.toString(index))
+                .queryParam("num", Integer.toString(num));
+        if (outputfields.length() > 0)
+            ub.queryParam("outputfields", outputfields);
+        final String uri = ub.toString();
+
+        return uri;
+    }
+
+    /**
+     * Build the Request object for the REST call.
+     */
+    private Request buildRequest(DmsCredentials cred, String uri)
+            throws DmsException {
+        final Request request = new Request(Method.GET, uri);
+
+        // Add the client authentication to the call
+        // final ChallengeScheme scheme1 = ChallengeScheme.HTTP_BASIC;
+        // final ChallengeResponse authentication = new
+        // ChallengeResponse(scheme,
+        // "geus", "xxx");
+
+        // authentication
+        // .getParameters()
+        // .add(
+        // 
NegotiateFilter.NegotiateAuthenticationHelper.NEGOTIATE_TOKEN_PARAM_NAME,
+        // createAuthToken(cred.getSubject()));
+
+        
+        // Use Negotiate authentication
+        final ChallengeScheme scheme = NegotiateFilter.HTTP_NEGOTIATE;
+
+        // Place the Negotiate token in the password field
+        final ChallengeResponse authentication = new 
ChallengeResponse(scheme,
+                "", createAuthToken(cred.getSubject()));
+        
+        request.setChallengeResponse(authentication);
+        return request;
+    }
+
+    /**
+     * Fetch the next batch for search hits using a REST call.
+     * 
+     * <code>hits</code> will contain an iterator to the fetched data.
+     * <code>nextElement</code> will be set to the first new hit or null if 
no
+     * further hits could be fetched.
+     * 
+     * @throws DmsException
+     */
+    private void fetch() throws DmsException {
+        if (lastBatch)
+            nextElement = null;
+        else {
+            String uri = buildRestSearchURI(query, fields, resultType, index,
+                    hitsPerBatch);
+            Request request = buildRequest(cred, uri);
+            logger.info("GET " + uri);
+            final Response response = client.handle(request);
+
+            if (response.getStatus().isSuccess()) {
+                DomRepresentation document = response.getEntityAsDom();
+                NodeSet result = document.getNodes("/Hits/Hit");
+                if (result.size() < hitsPerBatch)
+                    lastBatch = true;
+                hits = result.iterator();
+                if (hits.hasNext())
+                    nextElement = new RestQueryMatch(hits.next());
+                else
+                    nextElement = null;
+            } else if (response.getStatus().equals(
+                    Status.CLIENT_ERROR_UNAUTHORIZED)) {
+                throw new DmsException(ErrorType.AUTHENTICATION, null,
+                        "REST call failed", "Authentication failed");
+            } else {
+                throw new DmsException(ErrorType.INTERNAL, null,
+                        "REST call failed",
+                        "An unexpected status was returned: "
+                                + response.getStatus());
+            }
+        }
+    }
+
+    /**
+     * Nothing to do. The REST server cleans its state automatically.
+     * 
+     * @see ch.idok.service.common.Iterator#destroy()
+     */
+    public void destroy() throws DmsException {
+
+    }
+
+    /**
+     * @see ch.idok.service.common.Iterator#hasNext()
+     */
+    public boolean hasNext() {
+        if (nextElement == null)
+            return false;
+        else
+            return true;
+    }
+
+    /**
+     * @see ch.idok.service.common.Iterator#next()
+     */
+    public QueryMatch next() {
+        try {
+            QueryMatch result = nextElement();
+            if (result == null)
+                throw new NoSuchElementException();
+            return result;
+        } catch (DmsException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    /**
+     * @see ch.idok.service.common.Iterator#nextElement()
+     */
+    public QueryMatch nextElement() throws DmsException {
+        QueryMatch result = nextElement;
+        if (result == null)
+            return null;
+        else {
+            index += 1;
+            if (hits.hasNext())
+                nextElement = new RestQueryMatch(hits.next());
+            else {
+                fetch();
+            }
+            return result;
+        }
+    }
+
+    /**
+     * @see ch.idok.service.common.Iterator#remove()
+     */
+    public void remove() {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * Create a GSS-API token for the DMS service.
+     */
+    private String createAuthToken(Subject subject) throws DmsException {
+        final String serviceName_ = System
+                .getProperty("ch.idok.service.server.principal");
+        ServiceTokenAction action = new ServiceTokenAction(serviceName_);
+
+        // Push the subject into the current ACC
+        try {
+            Subject.doAsPrivileged(subject, action, null);
+            logger.fine("Successfully created service token for "
+                    + action.getServiceName() + " as "
+                    + AuthUtil.principalSetToString(subject.getPrincipals())
+                    + ".");
+            return action.getToken64();
+        } catch (java.security.PrivilegedActionException pae) {
+            if (pae.getCause() instanceof DmsException)
+                throw (DmsException) pae.getCause();
+            throw new DmsException(ErrorType.INTERNAL, null,
+                    "The privileged action threw an unknown exception", "", 
pae
+                            .getCause());
+        }
+
+    }
+
+}

Added: 
branches/rest/java/ch/idok/service/client/search/rest/RestSearchService.java
==============================================================================
--- (empty file)
+++ 
branches/rest/java/ch/idok/service/client/search/rest/RestSearchService.java  
      Tue Aug 26 17:36:47 2008
@@ -0,0 +1,47 @@
+package ch.idok.service.client.search.rest;
+
+import java.util.logging.Logger;
+
+import ch.idok.common.errorhandling.DmsException;
+import ch.idok.common.util.DmsCredentials;
+import ch.idok.service.client.rest.RestClientProvider;
+import ch.idok.service.common.Iterator;
+import ch.idok.service.common.search.QueryMatch;
+import ch.idok.service.common.search.SearchService;
+
+/**
+ * Client-side search service that obtains the results from the iDok REST 
server
+ */
+public class RestSearchService implements SearchService {
+
+    private final RestClientProvider restClientProvider;
+
+    private final Logger logger;
+
+    /**
+     * Constructor
+     */
+    public RestSearchService(RestClientProvider restClientProvider) {
+        this.restClientProvider = restClientProvider;
+        logger = restClientProvider.getLogger();
+    }
+
+    /**
+     * @see 
ch.idok.service.common.search.SearchService#listMetafields(ch.idok.common.util.DmsCredentials,
 java.lang.String)
+     */
+    public String[] listMetafields(DmsCredentials cred, String repository)
+            throws DmsException {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /**
+     * @see 
ch.idok.service.common.search.SearchService#query(ch.idok.common.util.DmsCredentials,
 java.lang.String, java.lang.String, long)
+     */
+    public Iterator<QueryMatch> query(DmsCredentials cred, String query,
+            String fields, long resultType) throws DmsException {
+        return new RestSearchIterator(logger, restClientProvider, cred, 
query,
+                fields, resultType);
+    }
+
+}