michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: package org.mozilla.gecko.background.announcements;
michael@0: 
michael@0: import java.io.IOException;
michael@0: import java.security.GeneralSecurityException;
michael@0: import java.util.ArrayList;
michael@0: import java.util.Date;
michael@0: import java.util.List;
michael@0: 
michael@0: import org.json.simple.JSONArray;
michael@0: import org.json.simple.JSONObject;
michael@0: import org.mozilla.gecko.background.common.log.Logger;
michael@0: import org.mozilla.gecko.sync.ExtendedJSONObject;
michael@0: import org.mozilla.gecko.sync.NonArrayJSONException;
michael@0: import org.mozilla.gecko.sync.net.AuthHeaderProvider;
michael@0: import org.mozilla.gecko.sync.net.BaseResource;
michael@0: import org.mozilla.gecko.sync.net.BaseResourceDelegate;
michael@0: import org.mozilla.gecko.sync.net.Resource;
michael@0: import org.mozilla.gecko.sync.net.SyncResponse;
michael@0: 
michael@0: import ch.boye.httpclientandroidlib.Header;
michael@0: import ch.boye.httpclientandroidlib.HttpResponse;
michael@0: import ch.boye.httpclientandroidlib.client.ClientProtocolException;
michael@0: import ch.boye.httpclientandroidlib.client.methods.HttpRequestBase;
michael@0: import ch.boye.httpclientandroidlib.impl.client.DefaultHttpClient;
michael@0: import ch.boye.httpclientandroidlib.impl.cookie.DateUtils;
michael@0: import ch.boye.httpclientandroidlib.protocol.HTTP;
michael@0: 
michael@0: /**
michael@0:  * Converts HTTP resource callbacks into AnnouncementsFetchDelegate callbacks.
michael@0:  */
michael@0: public class AnnouncementsFetchResourceDelegate extends BaseResourceDelegate {
michael@0:   private static final String ACCEPT_HEADER = "application/json;charset=utf-8";
michael@0: 
michael@0:   private static final String LOG_TAG = "AnnounceFetchRD";
michael@0: 
michael@0:   protected final long startTime;
michael@0:   protected AnnouncementsFetchDelegate delegate;
michael@0: 
michael@0:   public AnnouncementsFetchResourceDelegate(Resource resource, AnnouncementsFetchDelegate delegate) {
michael@0:     super(resource);
michael@0:     this.startTime = System.currentTimeMillis();
michael@0:     this.delegate  = delegate;
michael@0:   }
michael@0: 
michael@0:   @Override
michael@0:   public String getUserAgent() {
michael@0:     return delegate.getUserAgent();
michael@0:   }
michael@0: 
michael@0:   @Override
michael@0:   public void addHeaders(HttpRequestBase request, DefaultHttpClient client) {
michael@0:     super.addHeaders(request, client);
michael@0: 
michael@0:     // The basics.
michael@0:     request.addHeader("Accept-Language", delegate.getLocale().toString());
michael@0:     request.addHeader("Accept",          ACCEPT_HEADER);
michael@0: 
michael@0:     // We never want to keep connections alive.
michael@0:     request.addHeader("Connection", "close");
michael@0: 
michael@0:     // Set If-Modified-Since to avoid re-fetching content.
michael@0:     final String ifModifiedSince = delegate.getLastDate();
michael@0:     if (ifModifiedSince != null) {
michael@0:       Logger.info(LOG_TAG, "If-Modified-Since: " + ifModifiedSince);
michael@0:       request.addHeader("If-Modified-Since", ifModifiedSince);
michael@0:     }
michael@0: 
michael@0:     // Just in case.
michael@0:     request.removeHeaders("Cookie");
michael@0:   }
michael@0: 
michael@0:   private List<Announcement> parseBody(ExtendedJSONObject body) throws NonArrayJSONException {
michael@0:     List<Announcement> out = new ArrayList<Announcement>(1);
michael@0:     JSONArray snippets = body.getArray("announcements");
michael@0:     if (snippets == null) {
michael@0:       Logger.warn(LOG_TAG, "Missing announcements body. Returning empty.");
michael@0:       return out;
michael@0:     }
michael@0: 
michael@0:     for (Object s : snippets) {
michael@0:       try {
michael@0:         out.add(Announcement.parseAnnouncement(new ExtendedJSONObject((JSONObject) s)));
michael@0:       } catch (Exception e) {
michael@0:         Logger.warn(LOG_TAG, "Malformed announcement or display failed. Skipping.", e);
michael@0:       }
michael@0:     }
michael@0:     return out;
michael@0:   }
michael@0: 
michael@0:   @Override
michael@0:   public void handleHttpResponse(HttpResponse response) {
michael@0:     final Header dateHeader = response.getFirstHeader(HTTP.DATE_HEADER);
michael@0:     String date = null;
michael@0:     if (dateHeader != null) {
michael@0:       // Note that we are deliberately not validating the server time here.
michael@0:       // We pass it directly back to the server; we don't care about the
michael@0:       // contents, and if we reject a value we essentially re-initialize
michael@0:       // the client, which will cause stale announcements to be re-fetched.
michael@0:       date = dateHeader.getValue();
michael@0:     }
michael@0:     if (date == null) {
michael@0:       // Use local clock, because skipping is better than re-fetching.
michael@0:       date = DateUtils.formatDate(new Date());
michael@0:       Logger.warn(LOG_TAG, "No fetch date; using local time " + date);
michael@0:     }
michael@0: 
michael@0:     final SyncResponse r = new SyncResponse(response);    // For convenience.
michael@0:     try {
michael@0:       final int statusCode = r.getStatusCode();
michael@0:       Logger.debug(LOG_TAG, "Got announcements response: " + statusCode);
michael@0: 
michael@0:       if (statusCode == 204 || statusCode == 304) {
michael@0:         BaseResource.consumeEntity(response);
michael@0:         delegate.onNoNewAnnouncements(startTime, date);
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       if (statusCode == 200) {
michael@0:         final List<Announcement> snippets;
michael@0:         try {
michael@0:           snippets = parseBody(r.jsonObjectBody());
michael@0:         } catch (Exception e) {
michael@0:           delegate.onRemoteError(e);
michael@0:           return;
michael@0:         }
michael@0:         delegate.onNewAnnouncements(snippets, startTime, date);
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       if (statusCode == 400 || statusCode == 405) {
michael@0:         // We did something wrong.
michael@0:         Logger.warn(LOG_TAG, "We did something wrong. Oh dear.");
michael@0:         // Fall through.
michael@0:       }
michael@0: 
michael@0:       if (statusCode == 503 || statusCode == 500) {
michael@0:         Logger.warn(LOG_TAG, "Server issue: " + r.body());
michael@0:         delegate.onBackoff(r.retryAfterInSeconds());
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       // Otherwise, clean up.
michael@0:       delegate.onRemoteFailure(statusCode);
michael@0: 
michael@0:     } catch (Exception e) {
michael@0:       Logger.warn(LOG_TAG, "Failed to extract body.", e);
michael@0:       delegate.onRemoteError(e);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   @Override
michael@0:   public void handleHttpProtocolException(ClientProtocolException e) {
michael@0:     Logger.warn(LOG_TAG, "Protocol exception.", e);
michael@0:     delegate.onLocalError(e);
michael@0:   }
michael@0: 
michael@0:   @Override
michael@0:   public void handleHttpIOException(IOException e) {
michael@0:     Logger.warn(LOG_TAG, "IO exception.", e);
michael@0:     delegate.onLocalError(e);
michael@0:   }
michael@0: 
michael@0:   @Override
michael@0:   public void handleTransportException(GeneralSecurityException e) {
michael@0:     Logger.warn(LOG_TAG, "Transport exception.", e);
michael@0:     // Class this as a remote error, because it's probably something odd
michael@0:     // with SSL negotiation.
michael@0:     delegate.onRemoteError(e);
michael@0:   }
michael@0: 
michael@0:   /**
michael@0:    * Be very thorough in case the superclass implementation changes.
michael@0:    * We never want this to be an authenticated request.
michael@0:    */
michael@0:   @Override
michael@0:   public AuthHeaderProvider getAuthHeaderProvider() {
michael@0:     return null;
michael@0:   }
michael@0: }