Merge pull request #697 from mfietz/feature/downloader-if-modified-since

Downloader use If-Modified-Since HTTP header (Take 2)

4 files changed, 155 insertions, 53 deletions

diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadRequest.java b/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadRequest.java
index 75d6570b2..41bbd5ba6 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadRequest.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadRequest.java
@@ -6,6 +6,9 @@ import android.os.Parcelable;
 
 import org.apache.commons.lang3.Validate;
 
+import de.danoeh.antennapod.core.feed.FeedFile;
+import de.danoeh.antennapod.core.util.URLChecker;
+
 public class DownloadRequest implements Parcelable {
 
     private final String destination;
@@ -13,6 +16,7 @@ public class DownloadRequest implements Parcelable {
     private final String title;
     private String username;
     private String password;
+    private long ifModifiedSince;
     private boolean deleteOnFailure;
     private final long feedfileId;
     private final int feedfileType;
@@ -45,12 +49,26 @@ public class DownloadRequest implements Parcelable {
         this(destination, source, title, feedfileId, feedfileType, null, null, true, null);
     }
 
+    public DownloadRequest(Builder builder) {
+        this.destination = builder.destination;
+        this.source = builder.source;
+        this.title = builder.title;
+        this.feedfileId = builder.feedfileId;
+        this.feedfileType = builder.feedfileType;
+        this.username = builder.username;
+        this.password = builder.password;
+        this.ifModifiedSince = builder.ifModifiedSince;
+        this.deleteOnFailure = builder.deleteOnFailure;
+        this.arguments = (builder.arguments != null) ? builder.arguments : new Bundle();
+    }
+
     private DownloadRequest(Parcel in) {
         destination = in.readString();
         source = in.readString();
         title = in.readString();
         feedfileId = in.readLong();
         feedfileType = in.readInt();
+        ifModifiedSince = in.readLong();
         deleteOnFailure = (in.readByte() > 0);
         arguments = in.readBundle();
         if (in.dataAvail() > 0) {
@@ -77,6 +95,7 @@ public class DownloadRequest implements Parcelable {
         dest.writeString(title);
         dest.writeLong(feedfileId);
         dest.writeInt(feedfileType);
+        dest.writeLong(ifModifiedSince);
         dest.writeByte((deleteOnFailure) ? (byte) 1 : 0);
         dest.writeBundle(arguments);
         if (username != null) {
@@ -105,6 +124,7 @@ public class DownloadRequest implements Parcelable {
 
         DownloadRequest that = (DownloadRequest) o;
 
+        if (ifModifiedSince != that.ifModifiedSince) return false;
         if (deleteOnFailure != that.deleteOnFailure) return false;
         if (feedfileId != that.feedfileId) return false;
         if (feedfileType != that.feedfileType) return false;
@@ -131,6 +151,7 @@ public class DownloadRequest implements Parcelable {
         result = 31 * result + (title != null ? title.hashCode() : 0);
         result = 31 * result + (username != null ? username.hashCode() : 0);
         result = 31 * result + (password != null ? password.hashCode() : 0);
+        result = 31 * result + (int)ifModifiedSince;
         result = 31 * result + (deleteOnFailure ? 1 : 0);
         result = 31 * result + (int) (feedfileId ^ (feedfileId >>> 32));
         result = 31 * result + feedfileType;
@@ -210,6 +231,15 @@ public class DownloadRequest implements Parcelable {
         this.password = password;
     }
 
+    public DownloadRequest setIfModifiedSince(long time) {
+        this.ifModifiedSince = time;
+        return this;
+    }
+
+    public long getIfModifiedSince() {
+        return this.ifModifiedSince;
+    }
+
     public boolean isDeleteOnFailure() {
         return deleteOnFailure;
     }
@@ -217,4 +247,54 @@ public class DownloadRequest implements Parcelable {
     public Bundle getArguments() {
         return arguments;
     }
+
+    public static class Builder {
+        private String destination;
+        private String source;
+        private String title;
+        private String username;
+        private String password;
+        private long ifModifiedSince;
+        private boolean deleteOnFailure = false;
+        private long feedfileId;
+        private int feedfileType;
+        private Bundle arguments;
+
+        public Builder(String destination, FeedFile item) {
+            this.destination = destination;
+            this.source = URLChecker.prepareURL(item.getDownload_url());
+            this.title = item.getHumanReadableIdentifier();
+            this.feedfileId = item.getId();
+            this.feedfileType = item.getTypeAsInt();
+        }
+
+        public Builder deleteOnFailure(boolean deleteOnFailure) {
+            this.deleteOnFailure = deleteOnFailure;
+            return this;
+        }
+
+        public Builder ifModifiedSince(long time) {
+            this.ifModifiedSince = time;
+            return this;
+        }
+
+        public Builder withAuthentication(String username, String password) {
+            this.username = username;
+            this.password = password;
+            return this;
+        }
+
+        public DownloadRequest build() {
+            Validate.notNull(destination);
+            Validate.notNull(source);
+            Validate.notNull(title);
+            return new DownloadRequest(this);
+        }
+
+        public Builder withArguments(Bundle args) {
+            this.arguments = args;
+            return this;
+        }
+
+    }
 }
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/download/HttpDownloader.java b/core/src/main/java/de/danoeh/antennapod/core/service/download/HttpDownloader.java
index 6bfd9b4a0..7abb6df5e 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/download/HttpDownloader.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/download/HttpDownloader.java
@@ -7,6 +7,7 @@ import com.squareup.okhttp.OkHttpClient;
 import com.squareup.okhttp.Request;
 import com.squareup.okhttp.Response;
 import com.squareup.okhttp.ResponseBody;
+import com.squareup.okhttp.internal.http.HttpDate;
 
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.lang3.StringUtils;
@@ -21,6 +22,7 @@ import java.net.HttpURLConnection;
 import java.net.SocketTimeoutException;
 import java.net.URI;
 import java.net.UnknownHostException;
+import java.util.Date;
 
 import de.danoeh.antennapod.core.BuildConfig;
 import de.danoeh.antennapod.core.ClientConfig;
@@ -64,6 +66,15 @@ public class HttpDownloader extends Downloader {
             final URI uri = URIUtil.getURIFromRequestUrl(request.getSource());
             Request.Builder httpReq = new Request.Builder().url(uri.toURL())
                     .header("User-Agent", ClientConfig.USER_AGENT);
+            if(request.getIfModifiedSince() > 0) {
+                long threeDaysAgo = System.currentTimeMillis() - 1000*60*60*24*3;
+                if(request.getIfModifiedSince() > threeDaysAgo) {
+                    Date date = new Date(request.getIfModifiedSince());
+                    String httpDate = HttpDate.format(date);
+                    Log.d(TAG, "addHeader(\"If-Modified-Since\", \"" + httpDate + "\")");
+                    httpReq.addHeader("If-Modified-Since", httpDate);
+                }
+            }
 
             // add authentication information
             String userInfo = uri.getUserInfo();
@@ -83,7 +94,7 @@ public class HttpDownloader extends Downloader {
                 request.setSoFar(destination.length());
                 httpReq.addHeader("Range",
                         "bytes=" + request.getSoFar() + "-");
-                if (BuildConfig.DEBUG) Log.d(TAG, "Adding range header: " + request.getSoFar());
+                Log.d(TAG, "Adding range header: " + request.getSoFar());
             }
 
             Response response = httpClient.newCall(httpReq.build()).execute();
@@ -96,6 +107,12 @@ public class HttpDownloader extends Downloader {
             if (BuildConfig.DEBUG)
                 Log.d(TAG, "Response code is " + response.code());
 
+            if(!response.isSuccessful() && response.code() == HttpURLConnection.HTTP_NOT_MODIFIED) {
+                Log.d(TAG, "Feed '" + request.getSource() + "' not modified since last update, Download canceled");
+                onCancelled();
+                return;
+            }
+
             if (!response.isSuccessful() || response.body() == null) {
                 final DownloadError error;
                 final String details;
diff --git a/core/src/main/java/de/danoeh/antennapod/core/storage/DBTasks.java b/core/src/main/java/de/danoeh/antennapod/core/storage/DBTasks.java
index e73f9599d..e0e370b0d 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/storage/DBTasks.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/storage/DBTasks.java
@@ -298,7 +298,8 @@ public final class DBTasks {
     }
 
     /**
-     * Updates a specific Feed.
+     * Refresh a specific Feed. The refresh may get canceled if the feed does not seem to be modified
+     * and the last update was only few days ago.
      *
      * @param context Used for requesting the download.
      * @param feed    The Feed object.
@@ -311,9 +312,9 @@ public final class DBTasks {
     private static void refreshFeed(Context context, Feed feed, boolean loadAllPages) throws DownloadRequestException {
         Feed f;
         if (feed.getPreferences() == null) {
-            f = new Feed(feed.getDownload_url(), new Date(), feed.getTitle());
+            f = new Feed(feed.getDownload_url(), feed.getLastUpdate(), feed.getTitle());
         } else {
-            f = new Feed(feed.getDownload_url(), new Date(), feed.getTitle(),
+            f = new Feed(feed.getDownload_url(), feed.getLastUpdate(), feed.getTitle(),
                     feed.getPreferences().getUsername(), feed.getPreferences().getPassword());
         }
         f.setId(feed.getId());
diff --git a/core/src/main/java/de/danoeh/antennapod/core/storage/DownloadRequester.java b/core/src/main/java/de/danoeh/antennapod/core/storage/DownloadRequester.java
index d0cdad649..ca6aa0178 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/storage/DownloadRequester.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/storage/DownloadRequester.java
@@ -91,57 +91,53 @@ public class DownloadRequester {
     }
 
     private void download(Context context, FeedFile item, FeedFile container, File dest,
-                          boolean overwriteIfExists, String username, String password, boolean deleteOnFailure, Bundle arguments) {
+                          boolean overwriteIfExists, String username, String password,
+                          long ifModifiedSince, boolean deleteOnFailure, Bundle arguments) {
         final boolean partiallyDownloadedFileExists = item.getFile_url() != null;
-        if (!isDownloadingFile(item)) {
-            if (!isFilenameAvailable(dest.toString()) || (!partiallyDownloadedFileExists && dest.exists())) {
-                if (BuildConfig.DEBUG)
-                    Log.d(TAG, "Filename already used.");
-                if (isFilenameAvailable(dest.toString()) && overwriteIfExists) {
-                    boolean result = dest.delete();
-                    if (BuildConfig.DEBUG)
-                        Log.d(TAG, "Deleting file. Result: " + result);
-                } else {
-                    // find different name
-                    File newDest = null;
-                    for (int i = 1; i < Integer.MAX_VALUE; i++) {
-                        String newName = FilenameUtils.getBaseName(dest
-                                .getName())
-                                + "-"
-                                + i
-                                + FilenameUtils.EXTENSION_SEPARATOR
-                                + FilenameUtils.getExtension(dest.getName());
-                        if (BuildConfig.DEBUG)
-                            Log.d(TAG, "Testing filename " + newName);
-                        newDest = new File(dest.getParent(), newName);
-                        if (!newDest.exists()
-                                && isFilenameAvailable(newDest.toString())) {
-                            if (BuildConfig.DEBUG)
-                                Log.d(TAG, "File doesn't exist yet. Using "
-                                        + newName);
-                            break;
-                        }
-                    }
-                    if (newDest != null) {
-                        dest = newDest;
+        if (isDownloadingFile(item)) {
+                Log.e(TAG, "URL " + item.getDownload_url()
+                        + " is already being downloaded");
+            return;
+        }
+        if (!isFilenameAvailable(dest.toString()) || (!partiallyDownloadedFileExists && dest.exists())) {
+            Log.d(TAG, "Filename already used.");
+            if (isFilenameAvailable(dest.toString()) && overwriteIfExists) {
+                boolean result = dest.delete();
+                Log.d(TAG, "Deleting file. Result: " + result);
+            } else {
+                // find different name
+                File newDest = null;
+                for (int i = 1; i < Integer.MAX_VALUE; i++) {
+                    String newName = FilenameUtils.getBaseName(dest
+                            .getName())
+                            + "-"
+                            + i
+                            + FilenameUtils.EXTENSION_SEPARATOR
+                            + FilenameUtils.getExtension(dest.getName());
+                    Log.d(TAG, "Testing filename " + newName);
+                    newDest = new File(dest.getParent(), newName);
+                    if (!newDest.exists()
+                            && isFilenameAvailable(newDest.toString())) {
+                        Log.d(TAG, "File doesn't exist yet. Using " + newName);
+                        break;
                     }
                 }
+                if (newDest != null) {
+                    dest = newDest;
+                }
             }
-            if (BuildConfig.DEBUG)
-                Log.d(TAG,
-                        "Requesting download of url " + item.getDownload_url());
-            String baseUrl = (container != null) ? container.getDownload_url() : null;
-            item.setDownload_url(URLChecker.prepareURL(item.getDownload_url(), baseUrl));
-
-            DownloadRequest request = new DownloadRequest(dest.toString(),
-                    URLChecker.prepareURL(item.getDownload_url()), item.getHumanReadableIdentifier(),
-                    item.getId(), item.getTypeAsInt(), username, password, deleteOnFailure, arguments);
-
-            download(context, request);
-        } else {
-            Log.e(TAG, "URL " + item.getDownload_url()
-                    + " is already being downloaded");
         }
+        Log.d(TAG, "Requesting download of url " + item.getDownload_url());
+        String baseUrl = (container != null) ? container.getDownload_url() : null;
+        item.setDownload_url(URLChecker.prepareURL(item.getDownload_url(), baseUrl));
+
+        DownloadRequest.Builder builder = new DownloadRequest.Builder(dest.toString(), item)
+                .withAuthentication(username, password)
+                .ifModifiedSince(ifModifiedSince)
+                .deleteOnFailure(deleteOnFailure)
+                .withArguments(arguments);
+        DownloadRequest request = builder.build();
+        download(context, request);
     }
 
     /**
@@ -163,18 +159,26 @@ public class DownloadRequester {
         return true;
     }
 
+    /**
+     * Downloads a feed
+     *
+     * @param context The application's environment.
+     * @param feed Feed to download
+     * @param loadAllPages Set to true to download all pages
+     */
     public synchronized void downloadFeed(Context context, Feed feed, boolean loadAllPages)
             throws DownloadRequestException {
         if (feedFileValid(feed)) {
             String username = (feed.getPreferences() != null) ? feed.getPreferences().getUsername() : null;
             String password = (feed.getPreferences() != null) ? feed.getPreferences().getPassword() : null;
+            long ifModifiedSince = feed.getLastUpdate().getTime();
 
             Bundle args = new Bundle();
             args.putInt(REQUEST_ARG_PAGE_NR, feed.getPageNr());
             args.putBoolean(REQUEST_ARG_LOAD_ALL_PAGES, loadAllPages);
 
             download(context, feed, null, new File(getFeedfilePath(context),
-                    getFeedfileName(feed)), true, username, password, true, args);
+                    getFeedfileName(feed)), true, username, password, ifModifiedSince, true, args);
         }
     }
 
@@ -187,7 +191,7 @@ public class DownloadRequester {
         if (feedFileValid(image)) {
             FeedFile container = (image.getOwner() instanceof FeedFile) ? (FeedFile) image.getOwner() : null;
             download(context, image, container, new File(getImagefilePath(context),
-                    getImagefileName(image)), false, null, null, false, null);
+                    getImagefileName(image)), false, null, null, 0, false, null);
         }
     }
 
@@ -213,7 +217,7 @@ public class DownloadRequester {
                         getMediafilename(feedmedia));
             }
             download(context, feedmedia, feed,
-                    dest, false, username, password, false, null);
+                    dest, false, username, password, 0, false, null);
         }
     }