org.apache.ambari.server.controller.metrics

Class RestMetricsPropertyProvider

java.lang.Object

org.apache.ambari.server.controller.internal.BaseProvider

org.apache.ambari.server.controller.internal.AbstractPropertyProvider

org.apache.ambari.server.controller.metrics.ThreadPoolEnabledPropertyProvider

org.apache.ambari.server.controller.metrics.RestMetricsPropertyProvider

All Implemented Interfaces:

PropertyProvider

public class RestMetricsPropertyProvider
extends ThreadPoolEnabledPropertyProvider

Resolves metrics like api/cluster/summary/nimbus.uptime For every metric, finds a relevant JSON value and returns it as a resource property.

This class will delegate responsibility for actually retrieving JSON data from a remote URL to the MetricsRetrievalService. It will also leverage the MetricsRetrievalService to provide cached Map instances for given URLs.

This is because the REST API workflow will attempt to read data from this provider during the context of a live Jetty thread. As a result, any attempt to read remote resources will cause a delay in returning a response code. On small clusters this mormally isn't a problem. However, as the cluster increases in size, the thread pool would not be able to keep pace and would eventually cause REST API request threads to wait while remote JSON data is retrieved.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.ambari.server.controller.metrics.ThreadPoolEnabledPropertyProvider

ThreadPoolEnabledPropertyProvider.Ticket

Field Summary

Fields

Modifier and Type	Field and Description
static String	DOCUMENT_PATH_SEPARATOR Symbol that separates names of nested JSON sections in metrics path
static String	URL_PATH_SEPARATOR String that separates JSON URL from path inside JSON in metrics path

Fields inherited from class org.apache.ambari.server.controller.metrics.ThreadPoolEnabledPropertyProvider

healthyStates, hostNamePropertyId

Method Summary

Modifier and Type	Method and Description
Set<String>	checkPropertyIds(Set<String> propertyIds) Check whether the set of given property ids is supported by this resource provider.
protected Resource	populateResource(Resource resource, Request request, Predicate predicate, ThreadPoolEnabledPropertyProvider.Ticket ticket) Populate a resource by obtaining the requested REST properties.
protected String	resolvePort(Cluster cluster, String hostname, String componentName, Map<String,String> metricsProperties, String protocol) If protocol is equal to HTTPS_PROTOCOL than returns HTTPS_PORT_PROPERTY_NAME_PROPERTY value from PORT_CONFIG_TYPE_PROPERTY else uses port_config_type, port_property_name, default_port parameters from metricsProperties to find out right port value for service

Methods inherited from class org.apache.ambari.server.controller.metrics.ThreadPoolEnabledPropertyProvider

getCacheKeyForException, getHost, getSpec, init, isRequestedPropertyId, logException, populateResources, rethrowSystemException, setPopulateTimeout

Methods inherited from class org.apache.ambari.server.controller.internal.AbstractPropertyProvider

checkAuthorizationForMetrics, checkPropertyCategory, getClustersNameFromResources, getClustersResourceId, getComponentMetrics, getPropertyInfoMap, getResourceTypeFromResources, getValue, isSupportedPropertyId, substituteArgument, updateComponentMetricMap, updatePropertyInfo, updatePropertyInfoMap

Methods inherited from class org.apache.ambari.server.controller.internal.BaseProvider

checkCategory, checkConfigPropertyIds, containsArguments, getCategoryIds, getPropertyIds, getRegexEntry, getRegexGroups, getRequestPropertyIds, isPatternKey, isPropertyCategoryRequested, isPropertyEntryRequested, isPropertyRequested, setResourceProperty

Methods inherited from class java.lang.Object

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

Field Detail

URL_PATH_SEPARATOR

public static final String URL_PATH_SEPARATOR

String that separates JSON URL from path inside JSON in metrics path

See Also:

Constant Field Values

DOCUMENT_PATH_SEPARATOR

public static final String DOCUMENT_PATH_SEPARATOR

Symbol that separates names of nested JSON sections in metrics path

See Also:

Constant Field Values

Method Detail

populateResource

protected Resource populateResource(Resource resource,
                                    Request request,
                                    Predicate predicate,
                                    ThreadPoolEnabledPropertyProvider.Ticket ticket)
                             throws SystemException

Populate a resource by obtaining the requested REST properties.

Specified by:

populateResource in class ThreadPoolEnabledPropertyProvider

Parameters:

resource - the resource to be populated

request - the request

predicate - the predicate

Returns:

the populated resource; null if the resource should NOT be part of the result set for the given predicate

Throws:

SystemException

checkPropertyIds

public Set<String> checkPropertyIds(Set<String> propertyIds)

Description copied from interface: PropertyProvider

Check whether the set of given property ids is supported by this resource provider.

Specified by:

checkPropertyIds in interface PropertyProvider

Overrides:

checkPropertyIds in class BaseProvider

Returns:

a subset of the given property id set containing any property ids not supported by this resource provider. An empty return set indicates that all of the given property ids are supported.

resolvePort

protected String resolvePort(Cluster cluster,
                             String hostname,
                             String componentName,
                             Map<String,String> metricsProperties,
                             String protocol)
                      throws org.apache.ambari.server.AmbariException

If protocol is equal to HTTPS_PROTOCOL than returns HTTPS_PORT_PROPERTY_NAME_PROPERTY value from PORT_CONFIG_TYPE_PROPERTY else uses port_config_type, port_property_name, default_port parameters from metricsProperties to find out right port value for service

Returns:

determines REST port for service

Throws:

org.apache.ambari.server.AmbariException