add API to return Uri for the given downloaded file id & get mimetype

Change-Id: I1f5dd734e394db0056579a3a0c26862fee27981e

4 files changed, 125 insertions, 5 deletions

diff --git a/api/current.xml b/api/current.xml
index a3428db..263648d 100644
--- a/api/current.xml
+++ b/api/current.xml
@@ -26295,6 +26295,19 @@
 <parameter name="request" type="android.app.DownloadManager.Request">
 </parameter>
 </method>
+<method name="getUriForDownloadedFile"
+ return="android.net.Uri"
+ abstract="false"
+ native="false"
+ synchronized="false"
+ static="false"
+ final="false"
+ deprecated="not deprecated"
+ visibility="public"
+>
+<parameter name="id" type="long">
+</parameter>
+</method>
 <method name="openDownloadedFile"
  return="android.os.ParcelFileDescriptor"
  abstract="false"
@@ -26809,6 +26822,17 @@
 <parameter name="value" type="java.lang.String">
 </parameter>
 </method>
+<method name="allowScanningByMediaScanner"
+ return="void"
+ abstract="false"
+ native="false"
+ synchronized="false"
+ static="false"
+ final="false"
+ deprecated="not deprecated"
+ visibility="public"
+>
+</method>
 <method name="setAllowedNetworkTypes"
  return="android.app.DownloadManager.Request"
  abstract="false"
diff --git a/core/java/android/app/DownloadManager.java b/core/java/android/app/DownloadManager.java
index 592a63b..08ccab6 100644
--- a/core/java/android/app/DownloadManager.java
+++ b/core/java/android/app/DownloadManager.java
@@ -27,6 +27,7 @@ import android.net.Uri;
 import android.os.Environment;
 import android.os.ParcelFileDescriptor;
 import android.provider.Downloads;
+import android.util.Log;
 import android.util.Pair;
 
 import java.io.File;
@@ -284,6 +285,7 @@ public class DownloadManager {
     private static final String[] COLUMNS = new String[] {
         COLUMN_ID,
         COLUMN_MEDIAPROVIDER_URI,
+        Downloads.Impl.COLUMN_DESTINATION,
         COLUMN_TITLE,
         COLUMN_DESCRIPTION,
         COLUMN_URI,
@@ -294,13 +296,14 @@ public class DownloadManager {
         COLUMN_REASON,
         COLUMN_BYTES_DOWNLOADED_SO_FAR,
         COLUMN_LAST_MODIFIED_TIMESTAMP,
-        COLUMN_LOCAL_FILENAME
+        COLUMN_LOCAL_FILENAME,
     };
 
     // columns to request from DownloadProvider
     private static final String[] UNDERLYING_COLUMNS = new String[] {
         Downloads.Impl._ID,
         Downloads.Impl.COLUMN_MEDIAPROVIDER_URI,
+        Downloads.Impl.COLUMN_DESTINATION,
         Downloads.Impl.COLUMN_TITLE,
         Downloads.Impl.COLUMN_DESCRIPTION,
         Downloads.Impl.COLUMN_URI,
@@ -309,14 +312,14 @@ public class DownloadManager {
         Downloads.Impl.COLUMN_STATUS,
         Downloads.Impl.COLUMN_CURRENT_BYTES,
         Downloads.Impl.COLUMN_LAST_MODIFICATION,
-        Downloads.Impl.COLUMN_DESTINATION,
         Downloads.Impl.COLUMN_FILE_NAME_HINT,
         Downloads.Impl._DATA,
     };
 
     private static final Set<String> LONG_COLUMNS = new HashSet<String>(
             Arrays.asList(COLUMN_ID, COLUMN_TOTAL_SIZE_BYTES, COLUMN_STATUS, COLUMN_REASON,
-                          COLUMN_BYTES_DOWNLOADED_SO_FAR, COLUMN_LAST_MODIFIED_TIMESTAMP));
+                          COLUMN_BYTES_DOWNLOADED_SO_FAR, COLUMN_LAST_MODIFIED_TIMESTAMP,
+                          Downloads.Impl.COLUMN_DESTINATION));
 
     /**
      * This class contains all the information necessary to request a new download. The URI is the
@@ -348,6 +351,7 @@ public class DownloadManager {
         private boolean mRoamingAllowed = true;
         private int mAllowedNetworkTypes = ~0; // default to all network types allowed
         private boolean mIsVisibleInDownloadsUi = true;
+        private boolean mScannable = false;
 
         /**
          * This download is visible but only shows in the notifications
@@ -389,7 +393,10 @@ public class DownloadManager {
          * Set the local destination for the downloaded file. Must be a file URI to a path on
          * external storage, and the calling application must have the WRITE_EXTERNAL_STORAGE
          * permission.
-         *
+         * <p>
+         * The downloaded file is not scanned by MediaScanner.
+         * But it can be made scannable by calling {@link #allowScanningByMediaScanner()}.
+         * <p>
          * By default, downloads are saved to a generated filename in the shared download cache and
          * may be deleted by the system at any time to reclaim space.
          *
@@ -403,6 +410,9 @@ public class DownloadManager {
         /**
          * Set the local destination for the downloaded file to a path within the application's
          * external files directory (as returned by {@link Context#getExternalFilesDir(String)}.
+         * <p>
+         * The downloaded file is not scanned by MediaScanner.
+         * But it can be made scannable by calling {@link #allowScanningByMediaScanner()}.
          *
          * @param context the {@link Context} to use in determining the external files directory
          * @param dirType the directory type to pass to {@link Context#getExternalFilesDir(String)}
@@ -419,6 +429,9 @@ public class DownloadManager {
          * Set the local destination for the downloaded file to a path within the public external
          * storage directory (as returned by
          * {@link Environment#getExternalStoragePublicDirectory(String)}.
+         *<p>
+         * The downloaded file is not scanned by MediaScanner.
+         * But it can be made scannable by calling {@link #allowScanningByMediaScanner()}.
          *
          * @param dirType the directory type to pass to
          *        {@link Environment#getExternalStoragePublicDirectory(String)}
@@ -438,6 +451,14 @@ public class DownloadManager {
         }
 
         /**
+         * If the file to be downloaded is to be scanned by MediaScanner, this method
+         * should be called before {@link DownloadManager#enqueue(Request)} is called.
+         */
+        public void allowScanningByMediaScanner() {
+            mScannable = true;
+        }
+
+        /**
          * Add an HTTP header to be included with the download request.  The header will be added to
          * the end of the list.
          * @param header HTTP header name
@@ -583,6 +604,8 @@ public class DownloadManager {
                 values.put(Downloads.Impl.COLUMN_DESTINATION,
                            Downloads.Impl.DESTINATION_CACHE_PARTITION_PURGEABLE);
             }
+            // is the file supposed to be media-scannable?
+            values.put(Downloads.Impl.COLUMN_MEDIA_SCANNED, (mScannable) ? 0 : 2);
 
             if (!mRequestHeaders.isEmpty()) {
                 encodeHttpHeaders(values);
@@ -868,6 +891,58 @@ public class DownloadManager {
     }
 
     /**
+     * Returns {@link Uri} for the given downloaded file id, if the file is
+     * downloaded successfully. otherwise, null is returned.
+     *<p>
+     * If the specified downloaded file is in external storage (for example, /sdcard dir),
+     * then it is assumed to be safe for anyone to read and the returned {@link Uri} can be used
+     * by any app to access the downloaded file.
+     *
+     * @param id the id of the downloaded file.
+     * @return the {@link Uri} for the given downloaded file id, if donload was successful. null
+     * otherwise.
+     */
+    public Uri getUriForDownloadedFile(long id) {
+        // to check if the file is in cache, get its destination from the database
+        Query query = new Query().setFilterById(id);
+        Cursor cursor = null;
+        try {
+            cursor = query(query);
+            if (cursor == null) {
+                return null;
+            }
+            while (cursor.moveToFirst()) {
+                int status = cursor.getInt(cursor.getColumnIndexOrThrow(
+                        DownloadManager.COLUMN_STATUS));
+                if (DownloadManager.STATUS_SUCCESSFUL == status) {
+                    int indx = cursor.getColumnIndexOrThrow(
+                            Downloads.Impl.COLUMN_DESTINATION);
+                    int destination = cursor.getInt(indx);
+                    // TODO: if we ever add API to DownloadManager to let the caller specify
+                    // non-external storage for a donloaded file, then the following code
+                    // should also check for that destination.
+                    if (destination == Downloads.Impl.DESTINATION_CACHE_PARTITION ||
+                            destination == Downloads.Impl.DESTINATION_CACHE_PARTITION_NOROAMING ||
+                            destination == Downloads.Impl.DESTINATION_CACHE_PARTITION_PURGEABLE) {
+                        // return private uri
+                        return ContentUris.withAppendedId(Downloads.Impl.CONTENT_URI, id);
+                    } else {
+                        // return public uri
+                        return ContentUris.withAppendedId(
+                                Downloads.Impl.PUBLICLY_ACCESSIBLE_DOWNLOADS_URI, id);
+                    }
+                }
+            }
+        } finally {
+            if (cursor != null) {
+                cursor.close();
+            }
+        }
+        // downloaded file not found or its status is not 'successfully completed'
+        return null;
+    }
+
+    /**
      * Restart the given downloads, which must have already completed (successfully or not).  This
      * method will only work when called from within the download manager's process.
      * @param ids the IDs of the downloads
@@ -1088,6 +1163,9 @@ public class DownloadManager {
             if (column.equals(COLUMN_BYTES_DOWNLOADED_SO_FAR)) {
                 return getUnderlyingLong(Downloads.Impl.COLUMN_CURRENT_BYTES);
             }
+            if (column.equals(Downloads.Impl.COLUMN_DESTINATION)) {
+                return getUnderlyingLong(Downloads.Impl.COLUMN_DESTINATION);
+            }
             assert column.equals(COLUMN_LAST_MODIFIED_TIMESTAMP);
             return getUnderlyingLong(Downloads.Impl.COLUMN_LAST_MODIFICATION);
         }
diff --git a/core/java/android/provider/Downloads.java b/core/java/android/provider/Downloads.java
index 7054888..65adef9 100644
--- a/core/java/android/provider/Downloads.java
+++ b/core/java/android/provider/Downloads.java
@@ -87,6 +87,16 @@ public final class Downloads {
         public static final Uri ALL_DOWNLOADS_CONTENT_URI =
                 Uri.parse("content://downloads/all_downloads");
 
+        /** URI segment to access a publicly accessible downloaded file */
+        public static final String PUBLICLY_ACCESSIBLE_DOWNLOADS_URI_SEGMENT = "public_downloads";
+
+        /**
+         * The content URI for accessing publicly accessible downloads (i.e., it requires no
+         * permissions to access this downloaded file)
+         */
+        public static final Uri PUBLICLY_ACCESSIBLE_DOWNLOADS_URI =
+                Uri.parse("content://downloads/" + PUBLICLY_ACCESSIBLE_DOWNLOADS_URI_SEGMENT);
+
         /**
          * Broadcast Action: this is sent by the download manager to the app
          * that had initiated a download when that download completes. The
@@ -358,6 +368,13 @@ public final class Downloads {
          */
         public static final String COLUMN_MEDIAPROVIDER_URI = "mediaprovider_uri";
 
+        /**
+         * The column that is used to remember whether the media scanner was invoked.
+         * It can take the values: null or 0(not scanned), 1(scanned), 2 (not scannable).
+         * <P>Type: TEXT</P>
+         */
+        public static final String COLUMN_MEDIA_SCANNED = "scanned";
+
         /*
          * Lists the destinations that an application can specify for a download.
          */
diff --git a/core/jni/android_database_SQLiteDatabase.cpp b/core/jni/android_database_SQLiteDatabase.cpp
index 1b68ba9..7aeed98 100644
--- a/core/jni/android_database_SQLiteDatabase.cpp
+++ b/core/jni/android_database_SQLiteDatabase.cpp
@@ -78,7 +78,8 @@ static char *createStr(const char *path, short extra) {
 static void sqlLogger(void *databaseName, int iErrCode, const char *zMsg) {
     // skip printing this message if it is due to certain types of errors
     if (iErrCode == 0 || iErrCode == SQLITE_CONSTRAINT) return;
-    LOGI("sqlite returned: error code = %d, msg = %s\n", iErrCode, zMsg);
+    // print databasename, errorcode and msg
+    LOGI("sqlite returned: error code = %d, msg = %s, db=%s\n", iErrCode, zMsg, databaseName);
 }
 
 // register the logging func on sqlite. needs to be done BEFORE any sqlite3 func is called.