--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main/java/org/dive4elements/artifacts/httpclient/http/HttpClientImpl.java	Thu Apr 25 11:14:14 2013 +0200
@@ -0,0 +1,577 @@
+/*
+ * Copyright (c) 2010 by Intevation GmbH
+ *
+ * This program is free software under the LGPL (>=v2.1)
+ * Read the file LGPL.txt coming with the software for details
+ * or visit http://www.gnu.org/licenses/ if it does not exist.
+ */
+package de.intevation.artifacts.httpclient.http;
+
+import java.io.InputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.log4j.Logger;
+
+import org.restlet.Client;
+import org.restlet.Request;
+import org.restlet.Response;
+import org.restlet.data.ClientInfo;
+import org.restlet.data.Language;
+import org.restlet.data.MediaType;
+import org.restlet.data.Method;
+import org.restlet.data.Preference;
+import org.restlet.data.Protocol;
+import org.restlet.data.Status;
+import org.restlet.ext.xml.DomRepresentation;
+import org.restlet.representation.Representation;
+
+import org.w3c.dom.Document;
+
+import de.intevation.artifacts.httpclient.exceptions.ConnectionException;
+import de.intevation.artifacts.httpclient.http.response.DocumentResponseHandler;
+import de.intevation.artifacts.httpclient.http.response.ResponseHandler;
+import de.intevation.artifacts.httpclient.http.response.StreamResponseHandler;
+import de.intevation.artifacts.httpclient.objects.Artifact;
+import de.intevation.artifacts.httpclient.objects.ArtifactFactory;
+import de.intevation.artifacts.httpclient.utils.ArtifactProtocolUtils;
+import de.intevation.artifacts.httpclient.utils.ArtifactCreator;
+
+
+/**
+ * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
+ */
+public class HttpClientImpl implements HttpClient {
+
+    private static final Logger logger = Logger.getLogger(HttpClient.class);
+
+    /** The URL part of the resource to list the existing users of the server.*/
+    public static final String PATH_LIST_USERS = "/list-users";
+
+    /** The URL part of the resource to list the Collections owned by a specific
+     * user.*/
+    public static final String PATH_USER_COLLECTIONS = "/list-collections";
+
+    /** The URL part og the resource to create a new user on the server.*/
+    public static final String PATH_CREATE_USER = "/create-user";
+
+    /** The URL part og the resource to find an existing user on the server.*/
+    public static final String PATH_FIND_USER = "/find-user";
+
+    /** The URL part of the resource to call a specific service.*/
+    public static final String PATH_SERVICE = "/service";
+
+    /** The URL path of the resource to create new artifact collections.*/
+    public static final String PATH_CREATE_COLLECTION = "/create-collection";
+
+    /** The URL path of the resource to work with an artifact collections.*/
+    public static final String PATH_ACTION_COLLECTION = "/collection";
+
+    /** The URL path of the resource to work with an artifact collections.*/
+    public static final String PATH_OUT_COLLECTION = "/collection";
+
+    private String serverUrl;
+
+    private String localeString;
+
+    private static final ThreadLocal<Client> CLIENT =
+        new ThreadLocal<Client>() {
+            @Override
+            protected Client initialValue() {
+                logger.debug("create new HTTP client");
+                return new Client(Protocol.HTTP);
+            }
+         };
+
+    public HttpClientImpl(String serverUrl) {
+        this.serverUrl = serverUrl;
+    }
+
+
+    /**
+     * This constructor might be used to modify the request's locale manually.
+     * E.g. the localization should not be based on the configured browser
+     * locale, but site specific configuration - than you are able to set the
+     * locale in this constructor.
+     *
+     * @param serverUrl The url that is used for the request.
+     * @param localeString The string representation of the desired locale.
+     */
+    public HttpClientImpl(String serverUrl, String localeString) {
+        this(serverUrl);
+
+        this.localeString = localeString;
+    }
+
+
+    @Override
+    public ArtifactFactory[] getArtifactFactories()
+    throws ConnectionException
+    {
+        ResponseHandler handler = new DocumentResponseHandler();
+
+        try {
+            String    url   = serverUrl + "/factories";
+            Document result = (Document) handler.handle(doGet(url));
+
+            return ArtifactProtocolUtils.extractArtifactFactories(result);
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(
+                "Connection to server failed. No Factories recieved.");
+        }
+    }
+
+
+    /**
+     * This method creates a new artifact in the artifact server and returns
+     * this artifact. The new artifact is created using <i>creator</i>. If no
+     * {@link ArtifactCreator} is given (null), an {@link Artifact} is returned.
+     *
+     * @param doc The CREATE document.
+     * @param creator The {@link ArtifactCreator} that is used to extract the
+     * new artifact from response document of the server.
+     *
+     * @return the new artifact.
+     */
+    @Override
+    public Object create(Document doc, ArtifactCreator creator)
+    throws ConnectionException
+    {
+        ResponseHandler handler = new DocumentResponseHandler();
+
+        try {
+            String   url    = serverUrl + "/create";
+            Document result = (Document) handler.handle(doPost(url, doc));
+
+            return creator == null
+                ? ArtifactProtocolUtils.extractArtifact(result)
+                : creator.create(result);
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(
+                "Connection to server failed. No Artifact created.");
+        }
+    }
+
+
+    @Override
+    public Object describe(
+        Artifact        artifact,
+        Document        doc,
+        ResponseHandler handler)
+    throws ConnectionException
+    {
+        try {
+            String   url    = serverUrl + "/artifact/" + artifact.getUuid();
+            return handler.handle(doPost(url, doc));
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(
+                "Connection to server failed: " + ioe.getMessage());
+        }
+    }
+
+
+    @Override
+    public Object feed(Artifact artifact, Document doc, ResponseHandler handler)
+    throws ConnectionException
+    {
+        try {
+            String   url    = serverUrl + "/artifact/" + artifact.getUuid();
+            Document result = (Document) handler.handle(doPost(url, doc));
+
+            return result;
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(
+                "Connection to server failed: " + ioe.getMessage());
+        }
+    }
+
+
+    @Override
+    public Object advance(Artifact artifact, Document doc, ResponseHandler handler)
+    throws ConnectionException
+    {
+        try {
+            String   url    = serverUrl + "/artifact/" + artifact.getUuid();
+            Document result = (Document) handler.handle(doPost(url, doc));
+
+            return result;
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(
+                "Connection to server failed: " + ioe.getMessage());
+        }
+    }
+
+
+    @Override
+    public void out(
+        Artifact     artifact,
+        Document     doc,
+        String       target,
+        OutputStream out)
+    throws ConnectionException
+    {
+        try {
+            String url =
+                serverUrl
+                + "/artifact/"
+                + artifact.getUuid()
+                + "/" + target;
+
+            ResponseHandler handler = new StreamResponseHandler();
+
+            InputStream stream = (InputStream) handler.handle(doPost(url, doc));
+            try {
+                byte[] b = new byte[4096];
+                int i;
+                while ((i = stream.read(b)) >= 0) {
+                    out.write(b, 0, i);
+                }
+            }
+            finally {
+                stream.close();
+            }
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(
+                "Connection to server failed: " + ioe.getMessage());
+        }
+    }
+
+
+    //==============================
+    // HTTP specific methods
+    //==============================
+
+    private Response doPost(String url, Document body) throws IOException {
+        if (logger.isDebugEnabled()) {
+            logger.debug("Start HTTP-POST request to: " + url);
+        }
+
+        Client client   = getClient();
+        Request request = prepareRequest(Method.POST, url);
+
+        Representation representation = new DomRepresentation(
+            MediaType.APPLICATION_XML,
+            body);
+
+        request.setEntity(representation);
+        Response response = client.handle(request);
+
+        Status status = response.getStatus();
+        if (status.getCode() != 200) {
+            logger.error("Response status: " + status.getCode());
+            throw new IOException(status.getDescription());
+        }
+
+        return response;
+    }
+
+
+    private static Client getClient() {
+        return CLIENT.get();
+    }
+
+
+    private Response doGet(String url) throws IOException {
+        if (logger.isDebugEnabled()) {
+            logger.debug("Start HTTP-POST request to: "+ url);
+        }
+
+        Client client   = getClient();
+        Request request = prepareRequest(Method.GET, url);
+
+        Response response = client.handle(request);
+
+        Status status = response.getStatus();
+        if (status.getCode() != 200) {
+            logger.error("Response status: " + status.getCode());
+            throw new IOException(status.getDescription());
+        }
+
+        return response;
+    }
+
+
+    /**
+     * This method prepares the request object.
+     *
+     * @param method The HTTP method (GET,POST).
+     * @param url The URL used for the request.
+     *
+     * @return the request object.
+     */
+    private Request prepareRequest(Method method, String url) {
+        Request request = new Request(method, url);
+
+        ClientInfo info = request.getClientInfo();
+
+        setLocale(info);
+
+        request.setClientInfo(info);
+
+        return request;
+    }
+
+
+    /**
+     * This method is called to set the request's locale.
+     *
+     * @param info The ClientInfo that is used to provide request information.
+     */
+    private void setLocale(ClientInfo info) {
+        if (localeString == null) {
+            return;
+        }
+
+        List<Preference<Language>> accepted =
+            new ArrayList<Preference<Language>>();
+
+        Language lang = Language.valueOf(localeString);
+
+        if (lang != null) {
+            if (logger.isDebugEnabled()) {
+                logger.debug(
+                    "Set locale of the request object: " + lang.toString());
+            }
+
+            Preference<Language> pref = new Preference<Language>();
+            pref.setMetadata(lang);
+            accepted.add(pref);
+
+            info.setAcceptedLanguages(accepted);
+        }
+    }
+
+
+    //==============================
+    // Collection API
+    //==============================
+
+    /**
+     * This method triggers the artifact servers resource to create a new
+     * artifact collection.
+     *
+     * @param create The CREATE document for the collection.
+     * @param ownerId The uuid of the creator.
+     * @param handler The handler that is used to create the result object.
+     *
+     * @return a result object created by <i>handler</i>.
+     */
+    public Object createCollection(
+        Document        create,
+        String          ownerId,
+        ResponseHandler handler)
+    throws ConnectionException
+    {
+        String url = serverUrl + PATH_CREATE_COLLECTION + "/" + ownerId;
+
+        try {
+            return handler.handle(doPost(url, create));
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(ioe.getMessage(), ioe);
+        }
+    }
+
+
+    /**
+     * This method might be used to trigger a collection specific action. The
+     * action that is executed depends on the document <i>actionDoc</i>.
+     *
+     * @param actionDoc The document that describes the action to be executed.
+     * @param uuid      The uuid of the collection.
+     * @param handler   The handler that is used to create the result object.
+     *
+     * @return a result object created by <i>handler</i>.
+     */
+    public Object doCollectionAction(
+        Document        actionDoc,
+        String          uuid,
+        ResponseHandler handler)
+    throws ConnectionException
+    {
+        String url = serverUrl + PATH_ACTION_COLLECTION + "/" + uuid;
+
+        try {
+            return handler.handle(doPost(url, actionDoc));
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(ioe.getMessage(), ioe);
+        }
+    }
+
+
+    /**
+     * This method triggers the out() operation of a Collection. The result of
+     * this operation is written to <i>out</i> directly - there is no return
+     * value.
+     *
+     * @param doc The request document for the out() operation.
+     * @param uuid The identifier of the Collection.
+     * @param type The name of the output type.
+     * @param out The OutputStream.
+     */
+    public void collectionOut(
+        Document     doc,
+        String       uuid,
+        String       type,
+        OutputStream out)
+    throws ConnectionException
+    {
+        try {
+            InputStream stream = collectionOut(doc, uuid, type);
+
+            byte[] b = new byte[4096];
+            try {
+                int i;
+                while ((i = stream.read(b)) >= 0) {
+                    out.write(b, 0, i);
+                }
+            }
+            finally {
+                stream.close();
+            }
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(ioe.getMessage(), ioe);
+        }
+    }
+
+
+    /**
+     * This method triggers the out() operation of a Collection. The result of
+     * this operation is returned as an InputStream.
+     *
+     * @param doc The request document for the out() operation.
+     * @param uuid The identifier of the Collection.
+     * @param type The name of the output type.
+     *
+     * @return an InputStream.
+     */
+    public InputStream collectionOut(
+        Document    doc,
+        String      uuid,
+        String      type)
+    throws ConnectionException
+    {
+        String url = serverUrl + PATH_OUT_COLLECTION + "/" + uuid + "/" + type;
+
+        ResponseHandler handler = new StreamResponseHandler();
+
+        try {
+            return (InputStream) handler.handle(doPost(url, doc));
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(ioe.getMessage(), ioe);
+        }
+    }
+
+
+    /*******************************
+     * Service API
+     *******************************/
+
+     public Document callService(String url, String service, Document input)
+     throws ConnectionException
+     {
+         DocumentResponseHandler handler = new DocumentResponseHandler();
+
+         return (Document) callService(url, service, input, handler);
+     }
+
+
+     public Object callService(
+         String          url,
+         String          service,
+         Document        input,
+         ResponseHandler handler)
+     throws ConnectionException {
+        if (logger.isDebugEnabled()) {
+            logger.debug("Start service call to '" + service + "'");
+        }
+
+        try {
+            String serverUrl = url + PATH_SERVICE + "/" + service;
+            return handler.handle(doPost(serverUrl, input));
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(
+                "Connection to server failed: " + ioe.getMessage());
+        }
+    }
+
+
+    /*******************************
+     * Users API
+     *******************************/
+
+    public Document listUsers()
+    throws ConnectionException
+    {
+        ResponseHandler handler = new DocumentResponseHandler();
+        String    url           = serverUrl + PATH_LIST_USERS;
+
+        try {
+            return (Document) handler.handle(doGet(url));
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(ioe.getMessage(), ioe);
+        }
+    }
+
+
+    public Document listUserCollections(String userid)
+    throws ConnectionException
+    {
+        ResponseHandler handler = new DocumentResponseHandler();
+
+        String url = serverUrl + PATH_USER_COLLECTIONS + "/" + userid;
+
+        try {
+            return (Document) handler.handle(doGet(url));
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(ioe.getMessage(), ioe);
+        }
+    }
+
+    @Override
+    public Document createUser(Document doc)
+    throws ConnectionException {
+        ResponseHandler handler = new DocumentResponseHandler();
+
+        String url = this.serverUrl + PATH_CREATE_USER;
+
+        try {
+            return (Document) handler.handle(doPost(url, doc));
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(
+                "Connection to server failed: " + ioe.getMessage());
+        }
+    }
+
+    @Override
+    public Document findUser(Document doc)
+    throws ConnectionException {
+        ResponseHandler handler = new DocumentResponseHandler();
+
+        String url = this.serverUrl + PATH_FIND_USER;
+
+        try {
+            return (Document) handler.handle(doPost(url, doc));
+        }
+        catch (IOException ioe) {
+            throw new ConnectionException(
+                "Connection to server failed: " + ioe.getMessage());
+        }
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8: