com.yahoo.bard.webservice.web.handlers.workflow

Class DruidWorkflow

java.lang.Object

com.yahoo.bard.webservice.web.handlers.workflow.DruidWorkflow

All Implemented Interfaces:

RequestWorkflowProvider

@Singleton
public class DruidWorkflow
extends Object
implements RequestWorkflowProvider

The Druid Workflow proceeds until a druid data request is returned or an error response is written.

• Partial data filtering is attached to the response. (Feature flagged)
• Requests are routed by selecting a druid web service.
• The cache is checked for responses matching the query. (Feature flagged)
• Non UI requests may pass through an asynchronous druid query to test the aggregation cost.
• Requests are sent asynchronously to the druid web service

Field Summary

Fields

Modifier and Type	Field and Description
protected DataCache<?>	dataCache
protected com.fasterxml.jackson.databind.ObjectMapper	mapper
protected PartialDataHandler	partialDataHandler
protected PhysicalTableDictionary	physicalTableDictionary
protected QuerySigningService<?>	querySigningService
static String	REQUEST_WORKFLOW_TIMER
static String	RESPONSE_WORKFLOW_TIMER
protected VolatileIntervalsService	volatileIntervalsService
protected DruidWebService	webService
protected QueryWeightUtil	weightUtil

Constructor Summary

Constructors

Constructor and Description
DruidWorkflow(DataCache<?> dataCache, DruidWebService webService, QueryWeightUtil weightUtil, PhysicalTableDictionary physicalTableDictionary, PartialDataHandler partialDataHandler, QuerySigningService<?> querySigningService, VolatileIntervalsService volatileIntervalsService, com.fasterxml.jackson.databind.ObjectMapper mapper) Constructor.

Method Summary

Modifier and Type	Method and Description
DataRequestHandler	buildWorkflow() Construct a workflow instance with a starting point request handler.

Methods inherited from class java.lang.Object

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

Field Detail

RESPONSE_WORKFLOW_TIMER

public static final String RESPONSE_WORKFLOW_TIMER

See Also:

Constant Field Values

REQUEST_WORKFLOW_TIMER

public static final String REQUEST_WORKFLOW_TIMER

See Also:

Constant Field Values

dataCache

@NotNull
protected final DataCache<?> dataCache

webService

@NotNull
protected final DruidWebService webService

weightUtil

@NotNull
protected final QueryWeightUtil weightUtil

physicalTableDictionary

@NotNull
protected final PhysicalTableDictionary physicalTableDictionary

partialDataHandler

@NotNull
protected final PartialDataHandler partialDataHandler

querySigningService

@NotNull
protected final QuerySigningService<?> querySigningService

mapper

@NotNull
protected final com.fasterxml.jackson.databind.ObjectMapper mapper

volatileIntervalsService

@NotNull
protected final VolatileIntervalsService volatileIntervalsService

Constructor Detail

DruidWorkflow

@Inject
public DruidWorkflow(@NotNull
                             DataCache<?> dataCache,
                             DruidWebService webService,
                             QueryWeightUtil weightUtil,
                             PhysicalTableDictionary physicalTableDictionary,
                             PartialDataHandler partialDataHandler,
                             QuerySigningService<?> querySigningService,
                             VolatileIntervalsService volatileIntervalsService,
                             com.fasterxml.jackson.databind.ObjectMapper mapper)

Constructor.

Parameters:

dataCache - Response cache to use for caching Druid responses

webService - Web Service to use for UI-path queries

weightUtil - Utility for dealing with the weight check step

physicalTableDictionary - Collection of all physical tables

partialDataHandler - Handler for dealing with the partial data step

querySigningService - Service to sign a query based on it's segment metadata

volatileIntervalsService - Service to get volatile intervals from

mapper - JSON mapper

Method Detail

buildWorkflow

public DataRequestHandler buildWorkflow()

Description copied from interface: RequestWorkflowProvider

Construct a workflow instance with a starting point request handler.

The workflow should be acyclic, moving a request along until a response is submitted or delegated to an asynchronous response callback.

Specified by:

buildWorkflow in interface RequestWorkflowProvider

Returns:

The data request handler at the start of the workflow chain