org.apache.ambari.server.api.query.render

Class AlertSummaryGroupedRenderer

java.lang.Object

org.apache.ambari.server.api.query.render.BaseRenderer

org.apache.ambari.server.api.query.render.AlertSummaryRenderer

org.apache.ambari.server.api.query.render.AlertSummaryGroupedRenderer

All Implemented Interfaces:

Renderer

public class AlertSummaryGroupedRenderer
extends AlertSummaryRenderer

The AlertSummaryGroupedRenderer is used to format the results of queries to the alerts endpoint. Each alert instance returned from the backend is grouped by its alert definition and its state is then aggregated into the summary information for that definition.

The finalized structure is:

 {
   "alerts_summary_grouped" : [
     {
       "definition_id" : 1,
       "definition_name" : "datanode_process",
       "summary" : {
         "CRITICAL": {
           "count": 1,
           "maintenance_count" : 1,
           "original_timestamp": 1415372992337,
           "latest_text" : "TCP Connection Failure"
         },
         "OK": {
           "count": 1,
           "maintenance_count" : 0,
           "original_timestamp": 1415372992337,
           "latest_text" : "TCP OK"
         },
         "UNKNOWN": {
           "count": 0,
           "maintenance_count" : 0,
           "original_timestamp": 0
         },
        "WARN": {
          "count": 0,
          "maintenance_count" : 0,
          "original_timestamp": 0
         }
       }
     },
     {
       "definition_id" : 2,
       "definition_name" : "namenode_process",
       "summary" : {
         "CRITICAL": {
           "count": 1,
           "maintenance_count" : 0,
           "original_timestamp": 1415372992337
         },
         "OK": {
           "count": 1,
           "maintenance_count" : 0,
           "original_timestamp": 1415372992337
         },
         "UNKNOWN": {
           "count": 0,
           "maintenance_count" : 0,
           "original_timestamp": 0
         },
        "WARN": {
          "count": 0,
          "maintenance_count" : 0,
          "original_timestamp": 0
         }
       }
     }
   ]
 }
 

The nature of a Renderer is that it manipulates the dataset returned by a query. In the case of alert data, the query could potentially return thousands of results if there are thousands of nodes in the cluster. This could present a performance issue that can only be addressed by altering the incoming query and modifying it to instruct the backend to return a JPA SUM instead of a collection of entities.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AlertSummaryGroupedRenderer.AlertDefinitionSummary The AlertSummaryGroupedRenderer.AlertDefinitionSummary is a simple data structure for keeping track of each alert definition's summary information as the result set is being iterated over.

Constructor Summary

Constructors

Constructor and Description
AlertSummaryGroupedRenderer()

Method Summary

Modifier and Type	Method and Description
protected void	addRequiredAlertProperties(Set<String> properties) Adds properties to the backend request that are required by this renderer.
Result	finalizeResult(Result queryResult) Finalize the query results.
static Map<String,AlertSummaryGroupedRenderer.AlertDefinitionSummary>	generateEmptySummary(Long definitionId, String definitionName)
static void	updateSummary(Map<String,AlertSummaryGroupedRenderer.AlertDefinitionSummary> summaries, Long definitionId, String definitionName, AlertState state, Long originalTimestampObject, MaintenanceState maintenanceState, String alertText)

Methods inherited from class org.apache.ambari.server.api.query.render.AlertSummaryRenderer

finalizeProperties, getResultPostProcessor

Methods inherited from class org.apache.ambari.server.api.query.render.BaseRenderer

addKeys, addPrimaryKey, addSubResources, copyPropertiesToResult, ensureRequiredProperties, getSchema, init, isRequestWithNoProperties, populateSubResourceDefaults, requiresPropertyProviderInput

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.ambari.server.api.query.render.Renderer

init, requiresPropertyProviderInput

Constructor Detail

AlertSummaryGroupedRenderer

public AlertSummaryGroupedRenderer()

Method Detail

finalizeResult

public Result finalizeResult(Result queryResult)

Finalize the query results.

This will iterate over all of the nodes in the result tree and combine their AlertResourceProvider.ALERT_STATE into a single summary structure.

This will iterate over all of the nodes in the result tree and combine their AlertResourceProvider.ALERT_STATE into a single summary structure.

Specified by:

finalizeResult in interface Renderer

Overrides:

finalizeResult in class AlertSummaryRenderer

Parameters:

queryResult - result of query in native (default) format

Returns:

result in the format dictated by the renderer

updateSummary

public static void updateSummary(Map<String,AlertSummaryGroupedRenderer.AlertDefinitionSummary> summaries,
                                 Long definitionId,
                                 String definitionName,
                                 AlertState state,
                                 Long originalTimestampObject,
                                 MaintenanceState maintenanceState,
                                 String alertText)

generateEmptySummary

public static Map<String,AlertSummaryGroupedRenderer.AlertDefinitionSummary> generateEmptySummary(Long definitionId,
                                                                                                  String definitionName)

addRequiredAlertProperties

protected void addRequiredAlertProperties(Set<String> properties)

Adds properties to the backend request that are required by this renderer. This method currently adds AlertResourceProvider.ALERT_STATE and AlertResourceProvider.ALERT_ORIGINAL_TIMESTAMP.

Additionally adds AlertResourceProvider.ALERT_ID and AlertResourceProvider.ALERT_DEFINITION_NAME.

Overrides:

addRequiredAlertProperties in class AlertSummaryRenderer

Parameters:

properties - the properties collection to add to.