GREAT PACKAGE RESHUFFLE: Everything is now organised into frontend, backend and common (to frontend and backend) packages. Things may have been broken. Doc refresh.

1 files changed, 189 insertions, 0 deletions

diff --git a/src/uk/org/ury/backend/handlers/LibraryRequestHandler.java b/src/uk/org/ury/backend/handlers/LibraryRequestHandler.java
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+++ b/src/uk/org/ury/backend/handlers/LibraryRequestHandler.java
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+/**
+ * 
+ */
+package uk.org.ury.backend.handlers;
+
+import java.io.UnsupportedEncodingException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+
+import org.apache.http.HttpRequest;
+import org.apache.http.HttpResponse;
+import org.apache.http.HttpStatus;
+import org.apache.http.entity.StringEntity;
+import org.apache.http.protocol.HTTP;
+import org.apache.http.protocol.HttpContext;
+import org.json.simple.JSONValue;
+
+import uk.org.ury.backend.database.DatabaseDriver;
+import uk.org.ury.backend.database.UserClass;
+import uk.org.ury.backend.database.exceptions.ConnectionFailureException;
+import uk.org.ury.backend.database.exceptions.MissingCredentialsException;
+import uk.org.ury.backend.database.exceptions.QueryFailureException;
+import uk.org.ury.backend.server.AbstractRequestHandler;
+import uk.org.ury.backend.server.Server;
+import uk.org.ury.backend.server.exceptions.BadRequestException;
+import uk.org.ury.backend.server.exceptions.HandleFailureException;
+import uk.org.ury.backend.server.exceptions.HandlerNotFoundException;
+import uk.org.ury.backend.server.exceptions.HandlerSetupFailureException;
+import uk.org.ury.backend.server.exceptions.NotAHandlerException;
+import uk.org.ury.backend.server.exceptions.UnknownFunctionException;
+import uk.org.ury.common.library.LibraryUtils;
+import uk.org.ury.common.library.exceptions.EmptySearchException;
+import uk.org.ury.common.library.item.LibraryItem;
+import uk.org.ury.common.protocol.Directive;
+import uk.org.ury.common.protocol.Status;
+
+/**
+ * A request handler for library queries.
+ * 
+ * @author Matt Windsor
+ */
+public class LibraryRequestHandler extends AbstractRequestHandler {
+    /**
+     * Construct a new LibraryRequestHandler.
+     * 
+     * @param server
+     *            The instance of the URY server responsible for the request.
+     * 
+     * @param mount
+     *            The directory to which this handler is to be mounted.
+     */
+    public LibraryRequestHandler(Server server, String mount) {
+	super(server, mount);
+    }
+
+    /**
+     * Perform a library search, populating the response list.
+     * 
+     * @param parameters
+     *            A key-value map of parameters supplied with the server
+     *            request. Typically, the function parameter will detail the
+     *            function that the request handler is expected to perform.
+     * 
+     * @param response
+     *            The response list to populate.
+     * 
+     * @param server
+     *            The server providing database resources.
+     * 
+     * @throws HandleFailureException
+     *             if an error occurs that thwarts the handling of the request.
+     */
+
+    private void doSearch(Map<String, String> parameters,
+	    Map<String, Object> response, Server server)
+	    throws HandleFailureException {
+	if (parameters.containsKey("search") == false)
+	    throw new HandleFailureException("Search term is missing.");
+	else if (parameters.get("search") == null)
+	    throw new HandleFailureException("Search term is null.");
+
+	String search = parameters.get("search");
+	DatabaseDriver dd = null;
+
+	try {
+	    dd = server.getDatabaseConnection(UserClass.READ_ONLY);
+	} catch (MissingCredentialsException e) {
+	    throw new HandleFailureException(e.getMessage());
+	} catch (ConnectionFailureException e) {
+	    throw new HandleFailureException(e.getMessage());
+	}
+
+	try {
+	    List<Map<String, String>> itemArray = new ArrayList<Map<String, String>>();
+
+	    for (LibraryItem li : LibraryUtils.search(dd, search)) {
+		itemArray.add(li.asResponse());
+	    }
+
+	    response.put(Directive.ITEMS.toString(), itemArray);
+	} catch (QueryFailureException e) {
+	    throw new HandleFailureException(e.getMessage());
+	} catch (EmptySearchException e) {
+	    throw new HandleFailureException(e.getMessage());
+	}
+    }
+
+    /**
+     * Handle a HTTP GET request.
+     * 
+     * @param request
+     *            The HTTP request.
+     * 
+     * @param response
+     *            The response that the handler will populate during the
+     *            handling of the request.
+     * 
+     * @param context
+     *            The HTTP context.
+     * 
+     * @throws HandlerNotFoundException
+     *             if the client requested a request handler that could not be
+     *             found on the class path.
+     * 
+     * @throws HandlerSetupFailureException
+     *             if the handler was found but could not be set up (eg does not
+     *             implement appropriate interface or cannot be instantiated).
+     * 
+     * @throws HandleFailureException
+     *             if an appropriate handler was contacted, but it failed to
+     *             process the request.
+     * 
+     * @throws BadRequestException
+     *             if the request was malformed or invalid.
+     * 
+     * @throws NotAHandlerException
+     *             if the class requested to handle the request is not a
+     *             handler.
+     * 
+     * @throws UnknownFunctionException
+     *             if the request is for a path that does not correspond to one
+     *             of this handler's functions.
+     */
+    @Override
+    public void handleGet(HttpRequest request, HttpResponse response,
+	    HttpContext context) throws HandlerNotFoundException,
+	    HandlerSetupFailureException, HandleFailureException,
+	    BadRequestException, NotAHandlerException, UnknownFunctionException {
+	String path;
+	String uri = request.getRequestLine().getUri();
+	String query = getQueryString(uri);
+
+	if (query == null)
+	    path = uri.toLowerCase(Locale.ENGLISH);
+	else
+	    path = uri.split("\\?" + query)[0].toLowerCase(Locale.ENGLISH);
+
+	Map<String, Object> content = new HashMap<String, Object>();
+
+	if (path.equals("/library/tracks")) {
+	    try {
+		doSearch(parseQueryString(query), content, server);
+	    } catch (UnsupportedEncodingException e) {
+		throw new HandleFailureException(e.getMessage());
+	    }
+	} else {
+	    throw new UnknownFunctionException(path);
+	}
+
+	response.setStatusLine(request.getProtocolVersion(), HttpStatus.SC_OK,
+		"OK");
+
+	content.put(Directive.STATUS.toString(), Status.OK.toString());
+
+	StringEntity entity = null;
+
+	try {
+	    entity = new StringEntity(JSONValue.toJSONString(content));
+	} catch (UnsupportedEncodingException e) {
+	    throw new HandlerSetupFailureException(getClass().getName(), e);
+	}
+
+	entity.setContentType(HTTP.PLAIN_TEXT_TYPE);
+	response.setEntity(entity);
+    }
+}