org.apache.storm.assignments

Class InMemoryAssignmentBackend

java.lang.Object

org.apache.storm.assignments.InMemoryAssignmentBackend

All Implemented Interfaces:

AutoCloseable, ILocalAssignmentsBackend

public class InMemoryAssignmentBackend
extends Object
implements ILocalAssignmentsBackend

An assignment backend which will keep all assignments and id-info in memory. Only used if no backend is specified internal.

About thread safe: idToAssignment,idToName,nameToId are all memory cache in nimbus local, for

• idToAssignment: nimbus will modify it and supervisors will sync it at fixed interval, so the assignments would come to eventual consistency.
• idToName: storm submitting/killing is guarded by the same lock, a ConcurrentHashMap is ok.
• nameToId: same as idToName.

Constructor Summary

Constructors

Constructor and Description
InMemoryAssignmentBackend()

Method Summary

Modifier and Type	Method and Description
List<String>	assignments() List all the storm runtime ids of local assignments.
Map<String,Assignment>	assignmentsInfo() Get all the local assignments of local state.
void	clearStateForStorm(String stormId) Clear all the state for a storm.
void	close() Function to release resource.
void	deleteStormId(String stormName) Delete a local cache of stormId which is mapped to a specific storm name.
Assignment	getAssignment(String stormId) Get assignment as Assignment for a storm.
String	getStormId(String stormName) Get storm runtime id from local.
boolean	isSynchronized() Decide if the assignments is synchronized from remote state-store.
void	keepOrUpdateAssignment(String stormId, Assignment assignment) Keep a storm assignment to local state or update old assignment.
void	keepStormId(String stormName, String stormId) Keep a mapping storm-name -> storm-id to local state.
void	prepare(Map conf) Initial function for creating backend.
void	removeAssignment(String stormId)
void	setSynchronized() Mark this backend as synchronized when sync work is done.
void	syncRemoteAssignments(Map<String,byte[]> remote) Sync remote assignments to local, if remote is null, we will sync it from zk.
void	syncRemoteIds(Map<String,String> remote) Sync remote storm ids to local, will just used for nimbus.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

InMemoryAssignmentBackend

public InMemoryAssignmentBackend()

Method Detail

isSynchronized

public boolean isSynchronized()

Description copied from interface: ILocalAssignmentsBackend

Decide if the assignments is synchronized from remote state-store.

Specified by:

isSynchronized in interface ILocalAssignmentsBackend

setSynchronized

public void setSynchronized()

Description copied from interface: ILocalAssignmentsBackend

Mark this backend as synchronized when sync work is done.

Specified by:

setSynchronized in interface ILocalAssignmentsBackend

prepare

public void prepare(Map conf)

Description copied from interface: ILocalAssignmentsBackend

Initial function for creating backend.

Specified by:

prepare in interface ILocalAssignmentsBackend

Parameters:

conf - config

keepOrUpdateAssignment

public void keepOrUpdateAssignment(String stormId,
                                   Assignment assignment)

Description copied from interface: ILocalAssignmentsBackend

Keep a storm assignment to local state or update old assignment.

Specified by:

keepOrUpdateAssignment in interface ILocalAssignmentsBackend

Parameters:

stormId - storm runtime id

assignment - assignment as thrift

getAssignment

public Assignment getAssignment(String stormId)

Description copied from interface: ILocalAssignmentsBackend

Get assignment as Assignment for a storm.

Specified by:

getAssignment in interface ILocalAssignmentsBackend

Parameters:

stormId - storm runtime id

Returns:

assignment

removeAssignment

public void removeAssignment(String stormId)

Specified by:

removeAssignment in interface ILocalAssignmentsBackend

assignments

public List<String> assignments()

Description copied from interface: ILocalAssignmentsBackend

List all the storm runtime ids of local assignments.

Specified by:

assignments in interface ILocalAssignmentsBackend

Returns:

a list of storm ids

assignmentsInfo

public Map<String,Assignment> assignmentsInfo()

Description copied from interface: ILocalAssignmentsBackend

Get all the local assignments of local state.

Specified by:

assignmentsInfo in interface ILocalAssignmentsBackend

Returns:

mapping of storm-id -> assignment

syncRemoteAssignments

public void syncRemoteAssignments(Map<String,byte[]> remote)

Description copied from interface: ILocalAssignmentsBackend

Sync remote assignments to local, if remote is null, we will sync it from zk.

Specified by:

syncRemoteAssignments in interface ILocalAssignmentsBackend

Parameters:

remote - specific remote assignments, if it is null, it will sync from zookeeper[only used for nimbus]

keepStormId

public void keepStormId(String stormName,
                        String stormId)

Description copied from interface: ILocalAssignmentsBackend

Keep a mapping storm-name -> storm-id to local state.

Specified by:

keepStormId in interface ILocalAssignmentsBackend

Parameters:

stormName - storm name

stormId - storm runtime id

getStormId

public String getStormId(String stormName)

Description copied from interface: ILocalAssignmentsBackend

Get storm runtime id from local.

Specified by:

getStormId in interface ILocalAssignmentsBackend

Parameters:

stormName - name of a storm

Returns:

runtime storm id

syncRemoteIds

public void syncRemoteIds(Map<String,String> remote)

Description copied from interface: ILocalAssignmentsBackend

Sync remote storm ids to local, will just used for nimbus.

Specified by:

syncRemoteIds in interface ILocalAssignmentsBackend

Parameters:

remote - remote ids from state store

deleteStormId

public void deleteStormId(String stormName)

Description copied from interface: ILocalAssignmentsBackend

Delete a local cache of stormId which is mapped to a specific storm name.

Specified by:

deleteStormId in interface ILocalAssignmentsBackend

Parameters:

stormName - storm name

clearStateForStorm

public void clearStateForStorm(String stormId)

Description copied from interface: ILocalAssignmentsBackend

Clear all the state for a storm.

Specified by:

clearStateForStorm in interface ILocalAssignmentsBackend

Parameters:

stormId - storm id

close

public void close()

Description copied from interface: ILocalAssignmentsBackend

Function to release resource.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface ILocalAssignmentsBackend