RpcClientImpl.Connection (Apache HBase 1.2.12 API)

java.lang.Object
- java.lang.Thread
- - org.apache.hadoop.hbase.ipc.RpcClientImpl.Connection

All Implemented Interfaces:

Runnable

Enclosing class:

RpcClientImpl
```
protected class RpcClientImpl.Connection
extends Thread
```
Thread that reads responses and notifies callers. Each connection owns a socket connected to a remote address. Calls are multiplexed through this socket: responses may be delivered out of order.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

private class RpcClientImpl.Connection.CallSender
If the client wants to interrupt its calls easily (i.e.
- Nested classes/interfaces inherited from class java.lang.Thread
  Thread.State, Thread.UncaughtExceptionHandler

Nested Classes
Modifier and Type	Class and Description
`private class`	`RpcClientImpl.Connection.CallSender` If the client wants to interrupt its calls easily (i.e.

Field Summary

Fields
Modifier and Type	Field and Description
`private AuthMethod`	`authMethod`
`protected ConcurrentSkipListMap<Integer,Call>`	`calls`
`protected RpcClientImpl.Connection.CallSender`	`callSender`
`private Codec`	`codec`
`private org.apache.hadoop.io.compress.CompressionCodec`	`compressor`
`private org.apache.hadoop.hbase.protobuf.generated.RPCProtos.ConnectionHeader`	`header`
`protected DataInputStream`	`in`
`protected DataOutputStream`	`out`
`private Object`	`outLock`
`private int`	`reloginMaxBackoff`
`protected ConnectionId`	`remoteId`
`private HBaseSaslRpcClient`	`saslRpcClient`
`private InetSocketAddress`	`server`
`private String`	`serverPrincipal`
`protected AtomicBoolean`	`shouldCloseConnection`
`protected Socket`	`socket`
`private org.apache.hadoop.security.token.Token<? extends org.apache.hadoop.security.token.TokenIdentifier>`	`token`
`private boolean`	`useSasl`

Fields inherited from class java.lang.Thread
MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Constructors
Constructor and Description
`RpcClientImpl.Connection(ConnectionId remoteId, Codec codec, org.apache.hadoop.io.compress.CompressionCodec compressor)`

Method Summary

Methods
Modifier and Type	Method and Description
`private void`	`checkIsOpen()`
`protected void`	`cleanupCalls(boolean allCalls)` Cleanup the calls older than a given timeout, in milli seconds.
`protected void`	`close()` Close the connection.
`protected void`	`closeConnection()`
`private org.apache.hadoop.ipc.RemoteException`	`createRemoteException(org.apache.hadoop.hbase.protobuf.generated.RPCProtos.ExceptionResponse e)`
`private void`	`disposeSasl()`
`private void`	`doNotify()`
`InetSocketAddress`	`getRemoteAddress()`
`private org.apache.hadoop.hbase.protobuf.generated.RPCProtos.UserInformation`	`getUserInfo(org.apache.hadoop.security.UserGroupInformation ugi)`
`private void`	`handleConnectionFailure(int curRetries, int maxRetries, IOException ioe)` Handle connection failures If the current number of retries is equal to the max number of retries, stop retrying and throw the exception; Otherwise backoff N seconds and try connecting again.
`private void`	`handleSaslConnectionFailure(int currRetries, int maxRetries, Exception ex, Random rand, org.apache.hadoop.security.UserGroupInformation user)` If multiple clients with the same principal try to connect to the same server at the same time, the server assumes a replay attack is in progress.
`private boolean`	`isFatalConnectionException(org.apache.hadoop.hbase.protobuf.generated.RPCProtos.ExceptionResponse e)`
`protected boolean`	`markClosed(IOException e)`
`protected void`	`readResponse()`
`void`	`run()`
`protected void`	`setupConnection()`
`protected void`	`setupIOstreams()`
`private boolean`	`setupSaslConnection(InputStream in2, OutputStream out2)`
`private boolean`	`shouldAuthenticateOverKrb()`
`protected void`	`tracedWriteRequest(Call call, int priority, org.apache.htrace.Span span)`
`protected boolean`	`waitForWork()`
`private void`	`writeConnectionHeader()` Write the connection header.
`private void`	`writeConnectionHeaderPreamble(OutputStream outStream)` Write the RPC header:
`private void`	`writeRequest(Call call, int priority, org.apache.htrace.Span span)` Initiates a call by sending the parameter to the remote server.

Methods inherited from class java.lang.Thread
activeCount, checkAccess, clone, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

header

private org.apache.hadoop.hbase.protobuf.generated.RPCProtos.ConnectionHeader header

remoteId
```
protected ConnectionId remoteId
```

socket
```
protected Socket socket
```

in
```
protected DataInputStream in
```

out
```
protected DataOutputStream out
```

outLock
```
private Object outLock
```

server
```
private InetSocketAddress server
```

serverPrincipal
```
private String serverPrincipal
```

authMethod
```
private AuthMethod authMethod
```

useSasl
```
private boolean useSasl
```

token

private org.apache.hadoop.security.token.Token<? extends org.apache.hadoop.security.token.TokenIdentifier> token

saslRpcClient

private HBaseSaslRpcClient saslRpcClient

reloginMaxBackoff
```
private int reloginMaxBackoff
```

codec
```
private final Codec codec
```

compressor

private final org.apache.hadoop.io.compress.CompressionCodec compressor

calls

protected final ConcurrentSkipListMap<Integer,Call> calls

shouldCloseConnection

protected final AtomicBoolean shouldCloseConnection

callSender

protected final RpcClientImpl.Connection.CallSender callSender

Constructor Detail

RpcClientImpl.Connection

RpcClientImpl.Connection(ConnectionId remoteId,
                        Codec codec,
                        org.apache.hadoop.io.compress.CompressionCodec compressor)
                   throws IOException

Throws:: IOException

Method Detail

getUserInfo

private org.apache.hadoop.hbase.protobuf.generated.RPCProtos.UserInformation getUserInfo(org.apache.hadoop.security.UserGroupInformation ugi)

setupConnection

protected void setupConnection()
                        throws IOException

Throws:: IOException

closeConnection
```
protected void closeConnection()
```

handleConnectionFailure
```
private void handleConnectionFailure(int curRetries,
                           int maxRetries,
                           IOException ioe)
                              throws IOException
```
Handle connection failures If the current number of retries is equal to the max number of retries, stop retrying and throw the exception; Otherwise backoff N seconds and try connecting again. This Method is only called from inside setupIOstreams(), which is synchronized. Hence the sleep is synchronized; the locks will be retained.

Parameters:
curRetries - current number of retries
maxRetries - max number of retries allowed
ioe - failure reason

Throws:

IOException - if max number of retries is reached

checkIsOpen

private void checkIsOpen()
                  throws IOException

Throws:: IOException - if the connection is not open.

waitForWork

protected boolean waitForWork()
                       throws InterruptedException

Throws:: InterruptedException

getRemoteAddress

public InetSocketAddress getRemoteAddress()

run
```
public void run()
```
Specified by:

run in interface Runnable

Overrides:

run in class Thread

disposeSasl
```
private void disposeSasl()
```

shouldAuthenticateOverKrb

private boolean shouldAuthenticateOverKrb()
                                   throws IOException

Throws:: IOException

setupSaslConnection

private boolean setupSaslConnection(InputStream in2,
                          OutputStream out2)
                             throws IOException

Throws:: IOException

handleSaslConnectionFailure
```
private void handleSaslConnectionFailure(int currRetries,
                               int maxRetries,
                               Exception ex,
                               Random rand,
                               org.apache.hadoop.security.UserGroupInformation user)
                                  throws IOException,
                                         InterruptedException
```
If multiple clients with the same principal try to connect to the same server at the same time, the server assumes a replay attack is in progress. This is a feature of kerberos. In order to work around this, what is done is that the client backs off randomly and tries to initiate the connection again. The other problem is to do with ticket expiry. To handle that, a relogin is attempted.
The retry logic is governed by the shouldAuthenticateOverKrb() method. In case when the user doesn't have valid credentials, we don't need to retry (from cache or ticket). In such cases, it is prudent to throw a runtime exception when we receive a SaslException from the underlying authentication implementation, so there is no retry from other high level (for eg, HCM or HBaseAdmin).

Throws:

IOException

InterruptedException

setupIOstreams

protected void setupIOstreams()
                       throws IOException

Throws:: IOException

writeConnectionHeaderPreamble

private void writeConnectionHeaderPreamble(OutputStream outStream)
                                    throws IOException

Write the RPC header:

Throws:: IOException

writeConnectionHeader

private void writeConnectionHeader()
                            throws IOException

Write the connection header.

Throws:: IOException

close
```
protected void close()
```
Close the connection.

tracedWriteRequest

protected void tracedWriteRequest(Call call,
                      int priority,
                      org.apache.htrace.Span span)
                           throws IOException

Throws:: IOException

writeRequest
```
private void writeRequest(Call call,
                int priority,
                org.apache.htrace.Span span)
                   throws IOException
```
Initiates a call by sending the parameter to the remote server. Note: this is not called from the Connection thread, but by other threads.

Throws:

IOException
See Also:
readResponse()

doNotify
```
private void doNotify()
```

readResponse
```
protected void readResponse()
```

isFatalConnectionException

private boolean isFatalConnectionException(org.apache.hadoop.hbase.protobuf.generated.RPCProtos.ExceptionResponse e)

Returns:: True if the exception is a fatal connection exception.

createRemoteException

private org.apache.hadoop.ipc.RemoteException createRemoteException(org.apache.hadoop.hbase.protobuf.generated.RPCProtos.ExceptionResponse e)

Parameters:: e - exception to be wrapped
Returns:: RemoteException made from passed e

markClosed

protected boolean markClosed(IOException e)

cleanupCalls
```
protected void cleanupCalls(boolean allCalls)
```
Cleanup the calls older than a given timeout, in milli seconds.

Parameters:
allCalls - true for all calls, false for only the calls in timeout

Class RpcClientImpl.Connection

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

Field Summary

Fields inherited from class java.lang.Thread

Constructor Summary

Method Summary

Methods inherited from class java.lang.Thread

Methods inherited from class java.lang.Object

Field Detail

header

remoteId

socket

in

out

outLock

server

serverPrincipal

authMethod

useSasl

token

saslRpcClient

reloginMaxBackoff

codec

compressor

calls

shouldCloseConnection

callSender

Constructor Detail

RpcClientImpl.Connection

Method Detail

getUserInfo

setupConnection

closeConnection

handleConnectionFailure

checkIsOpen

waitForWork

getRemoteAddress

run

disposeSasl

shouldAuthenticateOverKrb

setupSaslConnection

handleSaslConnectionFailure

setupIOstreams

writeConnectionHeaderPreamble

writeConnectionHeader

close

tracedWriteRequest

writeRequest

doNotify

readResponse

isFatalConnectionException

createRemoteException

markClosed

cleanupCalls