/**
* Clone the specified snapshot. The clone will fail if the destination table has a snapshot or
* restore in progress.
*
* @param reqSnapshot Snapshot Descriptor from request
* @param tableName table to clone
* @param snapshot Snapshot Descriptor
* @param snapshotTableDesc Table Descriptor
* @param nonceGroup unique value to prevent duplicated RPC
* @param nonce unique value to prevent duplicated RPC
* @return procId the ID of the clone snapshot procedure
* @throws IOException
*/
private long cloneSnapshot(
final SnapshotDescription reqSnapshot,
final TableName tableName,
final SnapshotDescription snapshot,
final HTableDescriptor snapshotTableDesc,
final long nonceGroup,
final long nonce)
throws IOException {
MasterCoprocessorHost cpHost = master.getMasterCoprocessorHost();
HTableDescriptor htd = new HTableDescriptor(tableName, snapshotTableDesc);
if (cpHost != null) {
cpHost.preCloneSnapshot(reqSnapshot, htd);
}
long procId;
try {
procId = cloneSnapshot(snapshot, htd, nonceGroup, nonce);
} catch (IOException e) {
LOG.error(
"Exception occurred while cloning the snapshot "
+ snapshot.getName()
+ " as table "
+ tableName.getNameAsString(),
e);
throw e;
}
LOG.info("Clone snapshot=" + snapshot.getName() + " as table=" + tableName);
if (cpHost != null) {
cpHost.postCloneSnapshot(reqSnapshot, htd);
}
return procId;
}
/**
* Delete the specified snapshot
*
* @param snapshot
* @throws SnapshotDoesNotExistException If the specified snapshot does not exist.
* @throws IOException For filesystem IOExceptions
*/
public void deleteSnapshot(SnapshotDescription snapshot)
throws SnapshotDoesNotExistException, IOException {
// check to see if it is completed
if (!isSnapshotCompleted(snapshot)) {
throw new SnapshotDoesNotExistException(ProtobufUtil.createSnapshotDesc(snapshot));
}
String snapshotName = snapshot.getName();
// first create the snapshot description and check to see if it exists
FileSystem fs = master.getMasterFileSystem().getFileSystem();
Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshotName, rootDir);
// Get snapshot info from file system. The one passed as parameter is a "fake" snapshotInfo with
// just the "name" and it does not contains the "real" snapshot information
snapshot = SnapshotDescriptionUtils.readSnapshotInfo(fs, snapshotDir);
// call coproc pre hook
MasterCoprocessorHost cpHost = master.getMasterCoprocessorHost();
if (cpHost != null) {
cpHost.preDeleteSnapshot(snapshot);
}
LOG.debug("Deleting snapshot: " + snapshotName);
// delete the existing snapshot
if (!fs.delete(snapshotDir, true)) {
throw new HBaseSnapshotException("Failed to delete snapshot directory: " + snapshotDir);
}
// call coproc post hook
if (cpHost != null) {
cpHost.postDeleteSnapshot(snapshot);
}
}
/**
* Gets the list of all completed snapshots.
*
* @param snapshotDir snapshot directory
* @return list of SnapshotDescriptions
* @throws IOException File system exception
*/
private List<SnapshotDescription> getCompletedSnapshots(Path snapshotDir) throws IOException {
List<SnapshotDescription> snapshotDescs = new ArrayList<SnapshotDescription>();
// first create the snapshot root path and check to see if it exists
FileSystem fs = master.getMasterFileSystem().getFileSystem();
if (snapshotDir == null) snapshotDir = SnapshotDescriptionUtils.getSnapshotsDir(rootDir);
// if there are no snapshots, return an empty list
if (!fs.exists(snapshotDir)) {
return snapshotDescs;
}
// ignore all the snapshots in progress
FileStatus[] snapshots =
fs.listStatus(
snapshotDir, new SnapshotDescriptionUtils.CompletedSnaphotDirectoriesFilter(fs));
MasterCoprocessorHost cpHost = master.getMasterCoprocessorHost();
// loop through all the completed snapshots
for (FileStatus snapshot : snapshots) {
Path info = new Path(snapshot.getPath(), SnapshotDescriptionUtils.SNAPSHOTINFO_FILE);
// if the snapshot is bad
if (!fs.exists(info)) {
LOG.error("Snapshot information for " + snapshot.getPath() + " doesn't exist");
continue;
}
FSDataInputStream in = null;
try {
in = fs.open(info);
SnapshotDescription desc = SnapshotDescription.parseFrom(in);
if (cpHost != null) {
try {
cpHost.preListSnapshot(desc);
} catch (AccessDeniedException e) {
LOG.warn(
"Current user does not have access to "
+ desc.getName()
+ " snapshot. "
+ "Either you should be owner of this snapshot or admin user.");
// Skip this and try for next snapshot
continue;
}
}
snapshotDescs.add(desc);
// call coproc post hook
if (cpHost != null) {
cpHost.postListSnapshot(desc);
}
} catch (IOException e) {
LOG.warn("Found a corrupted snapshot " + snapshot.getPath(), e);
} finally {
if (in != null) {
in.close();
}
}
}
return snapshotDescs;
}
/**
* Restore the specified snapshot. The restore will fail if the destination table has a snapshot
* or restore in progress.
*
* @param reqSnapshot Snapshot Descriptor from request
* @param tableName table to restore
* @param snapshot Snapshot Descriptor
* @param snapshotTableDesc Table Descriptor
* @param nonceGroup unique value to prevent duplicated RPC
* @param nonce unique value to prevent duplicated RPC
* @return procId the ID of the restore snapshot procedure
* @throws IOException
*/
private long restoreSnapshot(
final SnapshotDescription reqSnapshot,
final TableName tableName,
final SnapshotDescription snapshot,
final HTableDescriptor snapshotTableDesc,
final long nonceGroup,
final long nonce)
throws IOException {
MasterCoprocessorHost cpHost = master.getMasterCoprocessorHost();
if (master
.getTableStateManager()
.isTableState(TableName.valueOf(snapshot.getTable()), TableState.State.ENABLED)) {
throw new UnsupportedOperationException(
"Table '"
+ TableName.valueOf(snapshot.getTable())
+ "' must be disabled in order to "
+ "perform a restore operation.");
}
// call Coprocessor pre hook
if (cpHost != null) {
cpHost.preRestoreSnapshot(reqSnapshot, snapshotTableDesc);
}
long procId;
try {
procId = restoreSnapshot(snapshot, snapshotTableDesc, nonceGroup, nonce);
} catch (IOException e) {
LOG.error(
"Exception occurred while restoring the snapshot "
+ snapshot.getName()
+ " as table "
+ tableName.getNameAsString(),
e);
throw e;
}
LOG.info("Restore snapshot=" + snapshot.getName() + " as table=" + tableName);
if (cpHost != null) {
cpHost.postRestoreSnapshot(reqSnapshot, snapshotTableDesc);
}
return procId;
}
/**
* Take a snapshot based on the enabled/disabled state of the table.
*
* @param snapshot
* @throws HBaseSnapshotException when a snapshot specific exception occurs.
* @throws IOException when some sort of generic IO exception occurs.
*/
public void takeSnapshot(SnapshotDescription snapshot) throws IOException {
// check to see if we already completed the snapshot
if (isSnapshotCompleted(snapshot)) {
throw new SnapshotExistsException(
"Snapshot '" + snapshot.getName() + "' already stored on the filesystem.",
ProtobufUtil.createSnapshotDesc(snapshot));
}
LOG.debug("No existing snapshot, attempting snapshot...");
// stop tracking "abandoned" handlers
cleanupSentinels();
// check to see if the table exists
HTableDescriptor desc = null;
try {
desc = master.getTableDescriptors().get(TableName.valueOf(snapshot.getTable()));
} catch (FileNotFoundException e) {
String msg = "Table:" + snapshot.getTable() + " info doesn't exist!";
LOG.error(msg);
throw new SnapshotCreationException(msg, e, ProtobufUtil.createSnapshotDesc(snapshot));
} catch (IOException e) {
throw new SnapshotCreationException(
"Error while geting table description for table " + snapshot.getTable(),
e,
ProtobufUtil.createSnapshotDesc(snapshot));
}
if (desc == null) {
throw new SnapshotCreationException(
"Table '" + snapshot.getTable() + "' doesn't exist, can't take snapshot.",
ProtobufUtil.createSnapshotDesc(snapshot));
}
SnapshotDescription.Builder builder = snapshot.toBuilder();
// if not specified, set the snapshot format
if (!snapshot.hasVersion()) {
builder.setVersion(SnapshotDescriptionUtils.SNAPSHOT_LAYOUT_VERSION);
}
User user = RpcServer.getRequestUser();
if (User.isHBaseSecurityEnabled(master.getConfiguration()) && user != null) {
builder.setOwner(user.getShortName());
}
snapshot = builder.build();
// call pre coproc hook
MasterCoprocessorHost cpHost = master.getMasterCoprocessorHost();
if (cpHost != null) {
cpHost.preSnapshot(snapshot, desc);
}
// if the table is enabled, then have the RS run actually the snapshot work
TableName snapshotTable = TableName.valueOf(snapshot.getTable());
if (master.getTableStateManager().isTableState(snapshotTable, TableState.State.ENABLED)) {
LOG.debug("Table enabled, starting distributed snapshot.");
snapshotEnabledTable(snapshot);
LOG.debug("Started snapshot: " + ClientSnapshotDescriptionUtils.toString(snapshot));
}
// For disabled table, snapshot is created by the master
else if (master.getTableStateManager().isTableState(snapshotTable, TableState.State.DISABLED)) {
LOG.debug("Table is disabled, running snapshot entirely on master.");
snapshotDisabledTable(snapshot);
LOG.debug("Started snapshot: " + ClientSnapshotDescriptionUtils.toString(snapshot));
} else {
LOG.error(
"Can't snapshot table '"
+ snapshot.getTable()
+ "', isn't open or closed, we don't know what to do!");
TablePartiallyOpenException tpoe =
new TablePartiallyOpenException(snapshot.getTable() + " isn't fully open.");
throw new SnapshotCreationException(
"Table is not entirely open or closed", tpoe, ProtobufUtil.createSnapshotDesc(snapshot));
}
// call post coproc hook
if (cpHost != null) {
cpHost.postSnapshot(snapshot, desc);
}
}