org.apache.hadoop.hive.shims
Interface HadoopShims

public interface HadoopShims

In order to be compatible with multiple versions of Hadoop, all parts of the Hadoop interface that are not cross-version compatible are encapsulated in an implementation of this class. Users should use the ShimLoader class as a factory to obtain an implementation of HadoopShims corresponding to the version of Hadoop currently on the classpath.

Nested Class Summary

static interface	HadoopShims.CombineFileInputFormatShim<K,V> CombineFileInputFormatShim.
static interface	HadoopShims.InputSplitShim InputSplitShim.
static class	HadoopShims.JobTrackerState
static interface	HadoopShims.MiniDFSShim Shim around the functions in MiniDFSCluster that Hive uses.

Field Summary

static org.apache.commons.logging.Log

LOG

Method Summary

void	closeAllForUGI(UserGroupInformation ugi) Get the UGI that the given job configuration will run as.
int	compareText(Text a, Text b) We define this function here to make the code compatible between hadoop 0.17 and hadoop 0.20.
int	createHadoopArchive(Configuration conf, Path parentDir, Path destDir, String archiveName)
UserGroupInformation	createProxyUser(String userName) Create the proxy ugi for the given userid
UserGroupInformation	createRemoteUser(String userName, List<String> groupNames) Used by metastore server to creates UGI object for a remote user.
<T> T	doAs(UserGroupInformation ugi, PrivilegedExceptionAction<T> pvea) Used by metastore server to perform requested rpc in client context.
boolean	fileSystemDeleteOnExit(FileSystem fs, Path path) Calls fs.deleteOnExit(path) if such a function exists.
long	getAccessTime(FileStatus file) return the last access time of the given file.
HadoopShims.CombineFileInputFormatShim	getCombineFileInputFormat()
long	getDefaultBlockSize(FileSystem fs, Path path) Get the default block size for the path.
short	getDefaultReplication(FileSystem fs, Path path) Get the default replication for a path.
URI	getHarUri(URI original, URI base, URI originalBase)
String	getInputFormatClassName()
String	getJobLauncherHttpAddress(Configuration conf) All references to jobtracker/resource manager http address in the configuration should be done through this shim
String	getJobLauncherRpcAddress(Configuration conf) All retrieval of jobtracker/resource manager rpc address in the configuration should be done through this shim
HadoopShims.JobTrackerState	getJobTrackerState(ClusterStatus clusterStatus) Convert the ClusterStatus to its Thrift equivalent: JobTrackerState.
HadoopShims.MiniDFSShim	getMiniDfs(Configuration conf, int numDataNodes, boolean format, String[] racks) Returns a shim to wrap MiniDFSCluster.
String	getShortUserName(UserGroupInformation ugi) Get the short name corresponding to the subject in the passed UGI In secure versions of Hadoop, this returns the short name (after undergoing the translation in the kerberos name rule mapping).
String	getTaskAttemptLogUrl(JobConf conf, String taskTrackerHttpAddress, String taskAttemptId) Constructs and Returns TaskAttempt Log Url or null if the TaskLogServlet is not available
String[]	getTaskJobIDs(TaskCompletionEvent t) getTaskJobIDs returns an array of String with two elements.
String	getTokenStrForm(String tokenSignature) Get the string form of the token given a token signature.
UserGroupInformation	getUGIForConf(Configuration conf)
void	inputFormatValidateInput(InputFormat fmt, JobConf conf) Calls fmt.validateInput(conf) if such a function exists.
boolean	isJobPreparing(RunningJob job) Return true if the job has not switched to RUNNING state yet and is still in PREP state
boolean	isLocalMode(Configuration conf) Check wether MR is configured to run in local-mode
boolean	isSecureShimImpl() Return true if the Shim is based on Hadoop Security APIs.
boolean	isSecurityEnabled() Return true if the hadoop configuration has security enabled
void	loginUserFromKeytab(String principal, String keytabFile) Perform kerberos login using the given principal and keytab
boolean	moveToAppropriateTrash(FileSystem fs, Path path, Configuration conf) Move the directory/file to trash.
JobContext	newJobContext(Job job)
TaskAttemptContext	newTaskAttemptContext(Configuration conf, Progressable progressable)
void	prepareJobOutput(JobConf conf) Hive uses side effect files exclusively for it's output.
void	setFloatConf(Configuration conf, String varName, float val) Wrapper for Configuration.setFloat, which was not introduced until 0.20.
void	setJobLauncherRpcAddress(Configuration conf, String val) All updates to jobtracker/resource manager rpc address in the configuration should be done through this shim
void	setTmpFiles(String prop, String files) If JobClient.getCommandLineConfig exists, sets the given property/value pair in that Configuration object.
void	setTokenStr(UserGroupInformation ugi, String tokenStr, String tokenService) Add a delegation token to the given ugi
String	unquoteHtmlChars(String item) Used by TaskLogProcessor to Remove HTML quoting from a string
boolean	usesJobShell() Return true if the current version of Hadoop uses the JobShell for command line interpretation.

Field Detail

LOG

static final org.apache.commons.logging.Log LOG

Method Detail

usesJobShell

boolean usesJobShell()

Return true if the current version of Hadoop uses the JobShell for command line interpretation.

getTaskAttemptLogUrl

String getTaskAttemptLogUrl(JobConf conf,
                            String taskTrackerHttpAddress,
                            String taskAttemptId)
                            throws MalformedURLException

Constructs and Returns TaskAttempt Log Url or null if the TaskLogServlet is not available

Returns:

TaskAttempt Log Url

Throws:

MalformedURLException

isJobPreparing

boolean isJobPreparing(RunningJob job)
                       throws IOException

Return true if the job has not switched to RUNNING state yet and is still in PREP state

Throws:

IOException

fileSystemDeleteOnExit

boolean fileSystemDeleteOnExit(FileSystem fs,
                               Path path)
                               throws IOException

Calls fs.deleteOnExit(path) if such a function exists.

Returns:

true if the call was successful

Throws:

IOException

inputFormatValidateInput

void inputFormatValidateInput(InputFormat fmt,
                              JobConf conf)
                              throws IOException

Calls fmt.validateInput(conf) if such a function exists.

Throws:

IOException

setTmpFiles

void setTmpFiles(String prop,
                 String files)

If JobClient.getCommandLineConfig exists, sets the given property/value pair in that Configuration object. This applies for Hadoop 0.17 through 0.19

getAccessTime

long getAccessTime(FileStatus file)

return the last access time of the given file.

Parameters:

file -

Returns:

last access time. -1 if not supported.

getMiniDfs

HadoopShims.MiniDFSShim getMiniDfs(Configuration conf,
                                   int numDataNodes,
                                   boolean format,
                                   String[] racks)
                                   throws IOException

Returns a shim to wrap MiniDFSCluster. This is necessary since this class was moved from org.apache.hadoop.dfs to org.apache.hadoop.hdfs

Throws:

IOException

compareText

int compareText(Text a,
                Text b)

We define this function here to make the code compatible between hadoop 0.17 and hadoop 0.20. Hive binary that compiled Text.compareTo(Text) with hadoop 0.20 won't work with hadoop 0.17 because in hadoop 0.20, Text.compareTo(Text) is implemented in org.apache.hadoop.io.BinaryComparable, and Java compiler references that class, which is not available in hadoop 0.17.

getCombineFileInputFormat

HadoopShims.CombineFileInputFormatShim getCombineFileInputFormat()

getInputFormatClassName

String getInputFormatClassName()

setFloatConf

void setFloatConf(Configuration conf,
                  String varName,
                  float val)

Wrapper for Configuration.setFloat, which was not introduced until 0.20.

getTaskJobIDs

String[] getTaskJobIDs(TaskCompletionEvent t)

getTaskJobIDs returns an array of String with two elements. The first element is a string representing the task id and the second is a string representing the job id. This is necessary as TaskID and TaskAttemptID are not supported in Haddop 0.17

createHadoopArchive

int createHadoopArchive(Configuration conf,
                        Path parentDir,
                        Path destDir,
                        String archiveName)
                        throws Exception

Throws:

Exception

getHarUri

URI getHarUri(URI original,
              URI base,
              URI originalBase)
              throws URISyntaxException

Throws:

URISyntaxException

prepareJobOutput

void prepareJobOutput(JobConf conf)

Hive uses side effect files exclusively for it's output. It also manages the setup/cleanup/commit of output from the hive client. As a result it does not need support for the same inside the MR framework This routine sets the appropriate options related to bypass setup/cleanup/commit support in the MR framework, but does not set the OutputFormat class.

unquoteHtmlChars

String unquoteHtmlChars(String item)

Used by TaskLogProcessor to Remove HTML quoting from a string

Parameters:

item - the string to unquote

Returns:

the unquoted string

closeAllForUGI

void closeAllForUGI(UserGroupInformation ugi)

Get the UGI that the given job configuration will run as. In secure versions of Hadoop, this simply returns the current access control context's user, ignoring the configuration.

getUGIForConf

UserGroupInformation getUGIForConf(Configuration conf)
                                   throws LoginException,
                                          IOException

Throws:

LoginException

IOException

doAs

<T> T doAs(UserGroupInformation ugi,
           PrivilegedExceptionAction<T> pvea)
       throws IOException,
              InterruptedException

Used by metastore server to perform requested rpc in client context.

Type Parameters:

T -

Parameters:

ugi -

pvea -

Throws:

IOException

InterruptedException

createRemoteUser

UserGroupInformation createRemoteUser(String userName,
                                      List<String> groupNames)

Used by metastore server to creates UGI object for a remote user.

Parameters:

userName - remote User Name

groupNames - group names associated with remote user name

Returns:

UGI created for the remote user.

getShortUserName

String getShortUserName(UserGroupInformation ugi)

Get the short name corresponding to the subject in the passed UGI In secure versions of Hadoop, this returns the short name (after undergoing the translation in the kerberos name rule mapping). In unsecure versions of Hadoop, this returns the name of the subject

isSecureShimImpl

boolean isSecureShimImpl()

Return true if the Shim is based on Hadoop Security APIs.

isSecurityEnabled

boolean isSecurityEnabled()

Return true if the hadoop configuration has security enabled

Returns:

getTokenStrForm

String getTokenStrForm(String tokenSignature)
                       throws IOException

Get the string form of the token given a token signature. The signature is used as the value of the "service" field in the token for lookup. Ref: AbstractDelegationTokenSelector in Hadoop. If there exists such a token in the token cache (credential store) of the job, the lookup returns that. This is relevant only when running against a "secure" hadoop release The method gets hold of the tokens if they are set up by hadoop - this should happen on the map/reduce tasks if the client added the tokens into hadoop's credential store in the front end during job submission. The method will select the hive delegation token among the set of tokens and return the string form of it

Parameters:

tokenSignature -

Returns:

the string form of the token found

Throws:

IOException

setTokenStr

void setTokenStr(UserGroupInformation ugi,
                 String tokenStr,
                 String tokenService)
                 throws IOException

Add a delegation token to the given ugi

Parameters:

ugi -

tokenStr -

tokenService -

Throws:

IOException

getJobTrackerState

HadoopShims.JobTrackerState getJobTrackerState(ClusterStatus clusterStatus)
                                               throws Exception

Convert the ClusterStatus to its Thrift equivalent: JobTrackerState. See MAPREDUCE-2455 for why this is a part of the shim.

Parameters:

clusterStatus -

Returns:

the matching JobTrackerState

Throws:

Exception - if no equivalent JobTrackerState exists

newTaskAttemptContext

TaskAttemptContext newTaskAttemptContext(Configuration conf,
                                         Progressable progressable)

newJobContext

JobContext newJobContext(Job job)

isLocalMode

boolean isLocalMode(Configuration conf)

Check wether MR is configured to run in local-mode

Parameters:

conf -

Returns:

getJobLauncherRpcAddress

String getJobLauncherRpcAddress(Configuration conf)

All retrieval of jobtracker/resource manager rpc address in the configuration should be done through this shim

Parameters:

conf -

Returns:

setJobLauncherRpcAddress

void setJobLauncherRpcAddress(Configuration conf,
                              String val)

All updates to jobtracker/resource manager rpc address in the configuration should be done through this shim

Parameters:

conf -

getJobLauncherHttpAddress

String getJobLauncherHttpAddress(Configuration conf)

All references to jobtracker/resource manager http address in the configuration should be done through this shim

Parameters:

conf -

Returns:

loginUserFromKeytab

void loginUserFromKeytab(String principal,
                         String keytabFile)
                         throws IOException

Perform kerberos login using the given principal and keytab

Throws:

IOException

moveToAppropriateTrash

boolean moveToAppropriateTrash(FileSystem fs,
                               Path path,
                               Configuration conf)
                               throws IOException

Move the directory/file to trash. In case of the symlinks or mount points, the file is moved to the trashbin in the actual volume of the path p being deleted

Parameters:

fs -

path -

conf -

Returns:

false if the item is already in the trash or trash is disabled

Throws:

IOException

getDefaultBlockSize

long getDefaultBlockSize(FileSystem fs,
                         Path path)

Get the default block size for the path. FileSystem alone is not sufficient to determine the same, as in case of CSMT the underlying file system determines that.

Parameters:

fs -

path -

Returns:

getDefaultReplication

short getDefaultReplication(FileSystem fs,
                            Path path)

Get the default replication for a path. In case of CSMT the given path will be used to locate the actual filesystem.

Parameters:

fs -

path -

Returns:

createProxyUser

UserGroupInformation createProxyUser(String userName)
                                     throws IOException

Create the proxy ugi for the given userid

Parameters:

userName -

Returns:

Throws:

IOException