client_namenode_translator::ClientNamenodeTranslator Class Reference

#include <ClientNamenodeProtocolImpl.h>

Public Member Functions
	ClientNamenodeTranslator (int port, zkclient::ZkNnClient *zk_arg)
std::string	getFileInfo (std::string)
std::string	mkdir (std::string)
std::string	destroy (std::string)
std::string	create (std::string)
std::string	getBlockLocations (std::string)
std::string	getServerDefaults (std::string)
std::string	renewLease (std::string)
std::string	complete (std::string)
std::string	setReplication (std::string)
std::string	addBlock (std::string input)
std::string	getListing (std::string input)
std::string	getEZForPath (std::string input)
std::string	setOwner (std::string input)
std::string	getContentSummary (std::string input)
std::string	modifyAclEntries (std::string input)
std::string	setPermission (std::string)
std::string	rename (std::string)
std::string	rename2 (std::string)
std::string	append (std::string)
std::string	updateBlockForPipeline (std::string)
std::string	updatePipeline (std::string)
std::string	recoverLease (std::string)
std::string	concat (std::string)
std::string	abandonBlock (std::string input)
std::string	fsync (std::string input)
std::string	finalizeUpgrade (std::string input)
std::string	getErasureCodingPolicies (std::string input)
std::string	getErasureCodingPolicy (std::string input)
std::string	setErasureCodingPolicy (std::string input)
int	getPort ()
RPCServer	getRPCServer ()

Detailed Description

The translator receives the rpc parameters from rpcserver. It then processes the message and does whatever is necessary, returing a serializes protobuff.

It communicates with zookeeper to construct the namespace and communicate with datanode

Member Function Documentation

std::string client_namenode_translator::ClientNamenodeTranslator::abandonBlock

(

std::string

input

)

The client can give up on a block by calling abandonBlock(). The client can then either obtain a new block, or complete or abandon the file. Any partial writes to the block will be discarded.

int client_namenode_translator::ClientNamenodeTranslator::getPort

(

)

Get the port this namenode listens on

RPCServer client_namenode_translator::ClientNamenodeTranslator::getRPCServer

(

)

Get the RPCServer this namenode uses to connect with clients

std::string client_namenode_translator::ClientNamenodeTranslator::rename2

(

std::string

input

)

When asked to do an unsupported command, we'll be returning a method-not-found proto. The code in question is very similar to GetErrorRPCHeader, but will actually occur further up - see rpcserver.cc's method handle_rpc. Whenever (iter != dispatch_table.end()) is false, it basically means that we couldn't find a corresponding method in this file here.

As such, it will go ahead and create the error header and send it back along, without ever having to call any methods in this file. So there is no need to ever worry about methods we just flat out don't support in this file.

That being said, the following is a short list of some common commands we don't support, and our reasons for not supporting them:

1. setReplication: The actual block replication is not expected to be performed during this method call. The blocks will be populated or removed in the background as the result of the routine block maintenance procedures. Basically, cannot set replication to something new.
2. append: Appends are not supported
3. concat: Effectively an append, so we don't support it
4. recoverLease: While we expect clients to renew their lease, we should never allow a client to "recover" a lease, since we only allow a write-once system As such, we cannot recover leases.

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The documentation for this class was generated from the following files:

• rice-namenode/include/ClientNamenodeProtocolImpl.h
• rice-namenode/source/ClientNamenodeProtocolImpl.cc