1page.title=bmgr 2parent.title=Tools 3parent.link=index.html 4@jd:body 5 6<!-- quickview box content here --> 7 8<div id="qv-wrapper"> 9<div id="qv"> 10 <h2>In this document</h2> 11 <ol> 12<li><a href="#backup">Forcing a Backup Operation</a></li> 13<li><a href="#restore">Forcing a Restore Operation</a></li> 14<li><a href="#other">Other Commands</a></li> 15 </ol> 16 17 <h2>See also</h2> 18 <ol> 19 <li><a href="{@docRoot}guide/topics/data/backup.html">Data Backup</a></li> 20 </ol> 21 22</div> 23</div> 24 25<!-- normal page content here --> 26 27<p><code>bmgr</code> is a shell tool you can use to interact with the Backup Manager 28on Android devices supporting API Level 8 or greater. It provides commands to induce backup 29and restore operations so that you don't need to repeatedly wipe data or take similar 30intrusive steps in order to test your application's backup agent. These commands are 31accessed via the <a href="{@docRoot}tools/help/adb.html">adb</a> shell. 32 33<p>For information about adding support for backup in your application, read <a 34href="{@docRoot}guide/topics/data/backup.html">Data Backup</a>, which includes a guide to testing 35your application using {@code bmgr}.</p> 36 37 38<h2 id="backup">Forcing a Backup Operation</h2> 39 40<p>Normally, your application must notify the Backup Manager when its data has changed, via {@link 41android.app.backup.BackupManager#dataChanged()}. The Backup Manager will then invoke your 42backup agent's {@link 43android.app.backup.BackupAgent#onBackup(ParcelFileDescriptor,BackupDataOutput,ParcelFileDescriptor) 44onBackup()} implementation at some time in the future. However, instead of calling {@link 45android.app.backup.BackupManager#dataChanged()}, you can invoke a backup request from the command 46line by running the <code>bmgr backup</code> command: 47 48 <pre class="no-pretty-print">adb shell bmgr backup <em><package></em></pre> 49 50<p><code><em><package></em></code> is the formal package name of the application you wish to 51schedule for 52backup. When you execute this backup command, your application's backup agent will be invoked to 53perform a backup operation at some time in the future (via your {@link 54android.app.backup.BackupAgent#onBackup(ParcelFileDescriptor,BackupDataOutput,ParcelFileDescriptor) 55onBackup()} method), though there is no guarantee when it will occur. However, you can force all 56pending backup operations to run immediately by using the <code>bmgr run</code> command: 57 58 <pre class="no-pretty-print">adb shell bmgr run</pre> 59 60<p>This causes a backup pass to execute immediately, invoking the backup agents of all applications 61that had previously called {@link android.app.backup.BackupManager#dataChanged()} since the 62last backup operation, plus any applications which had been manually scheduled for 63backup via <code>bmgr backup</code>. 64 65 66 67<h2 id="restore">Forcing a Restore Operation</h2> 68 69<p>Unlike backup operations, which are batched together and run on an occasional basis, restore 70operations execute immediately. The Backup Manager currently provides two kinds of restore 71operations. The first kind restores an entire device with the data that has been backed up. This 72is typically performed only when a device is first provisioned (to replicate settings and other 73saved state from the user's previous device) and is an operation that only the system can 74perform. The second kind of restore operation restores 75a single application to its "active" data set; that is, the application will abandon its current 76data and revert to the last-known-good data that is held in the current backup image. You can 77invoke this second restore operation with the {@link 78android.app.backup.BackupManager#requestRestore(RestoreObserver) requestRestore()} method. The 79Backup Manager will then invoke your backup agent's {@link 80android.app.backup.BackupAgent#onRestore(BackupDataInput,int,ParcelFileDescriptor) 81onRestore()} implementation. 82 83<p>While testing your application, you can immediately invoke the restore operation (bypassing the 84{@link android.app.backup.BackupManager#requestRestore(RestoreObserver) requestRestore()} method) 85for your application by using the <code>bmgr restore</code> command: 86 87 <pre class="no-pretty-print">adb shell bmgr restore <em><package></em></pre> 88 89<p><code><em><package></em></code> is the formal Java-style package name of the application 90participating in the backup/restore mechanism, which you would like to restore. The Backup 91Manager will immediately instantiate the application's backup agent and invoke it for restore. This 92will happen even if your application is not currently running. 93 94 95 96 97 98<h2 id="other">Other Commands</h2> 99 100<h3>Wiping data</h3> 101 102<p>The data for a single application can be erased from the active data set on demand. This is 103very useful while you're developing a backup agent, in case bugs lead you to write corrupt data 104or saved state information. You can wipe an application's data with the <code>bmgr wipe</code> 105command: 106 107 <pre class="no-pretty-print">adb shell bmgr wipe <em><package></em></pre> 108 109<p><code><em><package></em></code> is the formal package name of the application whose data 110you wish to 111erase. The next backup operation that the application's agent processes will look as 112though the application had never backed anything up before. 113 114 115<h3>Enabling and disabling backup</h3> 116 117<p>You can see whether the Backup Manager is operational at all with the <code>bmgr 118enabled</code> command: 119 120 <pre class="no-pretty-print">adb shell bmgr enabled</pre> 121 122<p>This might be useful if your application's backup agent is never being invoked for backup, to 123verify whether the operating system thinks it should be performing such operations at all.</p> 124 125<p>You can also directly disable or enable the Backup Manager with this command: 126 127 <pre class="no-pretty-print">adb shell bmgr enable <em><boolean></em></pre> 128 129<p><code><em><boolean></em></code> is either <code>true</code> or <code>false</code>. 130This is equivalent to disabling or enabling backup in the device's main Settings UI.</p> 131 132<p class="warning"><strong>Warning!</strong> When backup is disabled, the current backup transport 133will explicitly wipe 134the entire active data set from its backend storage. This is so that when a user says 135they do <em>not</em> want their data backed up, the Backup Manager respects that wish. No further 136data will be saved from the device, and no restore operations will be possible, unless the Backup 137Manager is re-enabled (either through Settings or through the above <code>bmgr</code> command). 138 139 140 141 142<!-- The following is not useful to applications, but may be some useful information some day... 143 144 145<h2 id="transports">Applying a Backup Transport</h2> 146 147<p>A "backup transport" is the code module responsible for moving backup and restore data 148to and from some storage location. A device can have multipe transports installed, though only 149one is active at any given time. Transports are identified by name. You can see what 150transports are available on your device or emulator by running the 151<code>bmgr list transports</code> command: 152 153 <pre class="no-pretty-print">adb shell bmgr list transports</pre> 154 155<p>The output of this command is a list of the transports available on the device. The currently 156active transport is flagged with a <code>*</code> character. Transport names may look like 157component names (for example, <code>android/com.android.internal.backup.LocalTransport</code>), 158but they need not be, and the strings are never used as direct class references. The use of 159a component-like naming scheme is simply for purposes of preventing name collisions. 160 161<p>You can change which transport is currently active from the command line as well: 162 163 <pre class="no-pretty-print">adb shell bmgr transport <em><name></em></pre> 164 165<p><code><em><name></em></code> is one of the names as printed by the <code>bmgr list 166transports</code> 167command. From this point forward, backup and restore operations will be directed through the 168newly-selected transport. Backup state tracking is managed separately for each transport, so 169switching back and forth between them will not corrupt the saved state. 170 171 172 173 174<h2 id="restoresets">Viewing Restore Sets</h2> 175 176<p>All of the application data that a device has written to its backup transport is tracked 177as a group that is collectively called a "restore set," because each data set is 178most often manipulated during a restore operation. When a device is provisioned for the first 179time, a new restore set is established. You can get a listing of all the restore sets available to 180the current transport by running the <code>bmgr list sets</code> command: 181 182 <pre class="no-pretty-print">adb shell bmgr list sets</pre> 183 184<p>The output is a listing of available restore sets, one per line. The first item on each line is 185a token (a hexadecimal value that identifies the restore set to the transport). Following 186the token is a string that briefly identifies the restore set. 187Only the token is used within the backup and restore mechanism. 188 189 190--> 191