org.apache.ambari.server.state.alert

Class AlertDefinitionHash

java.lang.Object

org.apache.ambari.server.state.alert.AlertDefinitionHash

public class AlertDefinitionHash
extends Object

The AlertDefinitionHash class is used to generate an MD5 hash for a list of AlertDefinitionEntitys. It is used in order to represent the state of a group of definitions by using AlertDefinitionEntity.getHash()

Field Summary

Fields

Modifier and Type	Field and Description
static String	NULL_MD5_HASH The hash returned when there are no definitions to hash.

Constructor Summary

Constructors

Constructor and Description
AlertDefinitionHash()

Method Summary

Modifier and Type	Method and Description
void	enqueueAgentCommands(long clusterId) Enqueue AlertDefinitionCommands for every host in the cluster so that they will receive a payload of alert definitions that they should be running.
void	enqueueAgentCommands(long clusterId, Collection<String> hosts) Enqueue AlertDefinitionCommands for every host specified so that they will receive a payload of alert definitions that they should be running.
Map<Long,AlertDefinition>	findByServiceComponent(long clusterId, String serviceName, String componentName)
Map<Long,AlertDefinition>	findByServiceMaster(long clusterId, String... serviceName)
Map<Long,Map<Long,AlertDefinition>>	getAlertDefinitions(Long hostId)
List<AlertDefinition>	getAlertDefinitions(String clusterName, String hostName) Gets the alert definitions for the specified host.
Set<String>	getAssociatedHosts(Cluster cluster, SourceType definitionSourceType, String definitionName, String definitionServiceName, String definitionComponentName) Gets the hosts that are associated with the specified definition.
String	getHash(String clusterName, String hostName) Gets a unique hash value reprssenting all of the alert definitions that should be scheduled to run on a given host.
void	invalidate(String hostName) Invalidates the cached hash for the specified agent host across all clusters.
void	invalidate(String clusterName, String hostName) Invalidates the cached hash for the specified agent host in the specified cluster.
void	invalidateAll() Invalidate all cached hashes causing subsequent lookups to recalculate.
Set<String>	invalidateHosts(AlertDefinition definition) Invalidate the hashes of any host that would be affected by the specified definition.
Set<String>	invalidateHosts(AlertDefinitionEntity definition) Invalidate the hashes of any host that would be affected by the specified definition.
boolean	isHashCached(String clusterName, String hostName) Gets whether the alert definition hash for the specified host has been calculated and cached.

Methods inherited from class java.lang.Object

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

Field Detail

NULL_MD5_HASH

public static final String NULL_MD5_HASH

The hash returned when there are no definitions to hash.

See Also:

Constant Field Values

Constructor Detail

AlertDefinitionHash

public AlertDefinitionHash()

Method Detail

getHash

public String getHash(String clusterName,
                      String hostName)

Gets a unique hash value reprssenting all of the alert definitions that should be scheduled to run on a given host.

This will not include alert definitions where the type is defined as SourceType.AGGREGATE since aggregate definitions are not scheduled to run on agent hosts.

Hash values from this method are cached.

Parameters:

clusterName - the cluster name (not null).

hostName - the host name (not null).

Returns:

the unique hash or "37a6259cc0c1dae299a7866489dff0bd" if none.

invalidateAll

public void invalidateAll()

Invalidate all cached hashes causing subsequent lookups to recalculate.

invalidate

public void invalidate(String hostName)

Invalidates the cached hash for the specified agent host across all clusters.

Parameters:

hostName - the host to invalidate the cache for (not null).

invalidate

public void invalidate(String clusterName,
                       String hostName)

Invalidates the cached hash for the specified agent host in the specified cluster.

Parameters:

clusterName - the name of the cluster (not null).

hostName - the host to invalidate the cache for (not null).

isHashCached

public boolean isHashCached(String clusterName,
                            String hostName)

Gets whether the alert definition hash for the specified host has been calculated and cached.

Parameters:

hostName - the host.

Returns:

true if the hash was calculated; false otherwise.

getAlertDefinitions

public List<AlertDefinition> getAlertDefinitions(String clusterName,
                                                 String hostName)

Gets the alert definitions for the specified host. This will include the following types of alert definitions:

• Service/Component alerts
• Service alerts where the host is a MASTER
• Host alerts that are not bound to a service

Parameters:

clusterName - the cluster name (not null).

hostName - the host name (not null).

Returns:

the alert definitions for the host, or an empty set (never null).

getAlertDefinitions

public Map<Long,Map<Long,AlertDefinition>> getAlertDefinitions(Long hostId)
                                                        throws org.apache.ambari.server.AmbariException

Throws:

org.apache.ambari.server.AmbariException

findByServiceComponent

public Map<Long,AlertDefinition> findByServiceComponent(long clusterId,
                                                        String serviceName,
                                                        String componentName)

findByServiceMaster

public Map<Long,AlertDefinition> findByServiceMaster(long clusterId,
                                                     String... serviceName)

invalidateHosts

public Set<String> invalidateHosts(AlertDefinitionEntity definition)

Invalidate the hashes of any host that would be affected by the specified definition. If the definition is an SourceType.AGGREGATE, this will return an empty set since aggregates do not affect hosts.

Parameters:

definition - the definition to use to find the hosts to invlidate (not null).

Returns:

the hosts that were invalidated, or an empty set (never null).

invalidateHosts

public Set<String> invalidateHosts(AlertDefinition definition)

Invalidate the hashes of any host that would be affected by the specified definition. If the definition is an SourceType.AGGREGATE, this will return an empty set since aggregates do not affect hosts.

Parameters:

definition - the definition to use to find the hosts to invlidate (not null).

Returns:

the hosts that were invalidated, or an empty set (never null).

getAssociatedHosts

public Set<String> getAssociatedHosts(Cluster cluster,
                                      SourceType definitionSourceType,
                                      String definitionName,
                                      String definitionServiceName,
                                      String definitionComponentName)

Gets the hosts that are associated with the specified definition. Each host returned is expected to be capable of running the alert. A change to the definition would entail contacting each returned host and invalidating their current alert definitions.

If the definition is an SourceType.AGGREGATE, this will return an empty set since aggregates do not affect hosts.

Parameters:

cluster -

definitionName -

definitionServiceName -

definitionComponentName -

Returns:

a set of all associated hosts or an empty set, never null.

enqueueAgentCommands

public void enqueueAgentCommands(long clusterId)

Enqueue AlertDefinitionCommands for every host in the cluster so that they will receive a payload of alert definitions that they should be running.

This method is typically called after invalidateAll() has caused a cache invalidation of all alert definitions.

Parameters:

clusterId - the ID of the cluster.

enqueueAgentCommands

public void enqueueAgentCommands(long clusterId,
                                 Collection<String> hosts)

Enqueue AlertDefinitionCommands for every host specified so that they will receive a payload of alert definitions that they should be running.

This method is typically called after invalidateHosts(AlertDefinitionEntity) has caused a cache invalidation of the alert definition hash.

Parameters:

clusterId - the ID of the cluster.

hosts - the hosts to push AlertDefinitionCommands for.