Package org.apache.druid.server

Class QueryLifecycle

java.lang.Object

org.apache.druid.server.QueryLifecycle

public class QueryLifecycle
extends Object

Class that helps a Druid server (broker, historical, etc) manage the lifecycle of a query that it is handling. It ensures that a query goes through the following stages, in the proper order:

1. Initialization (initialize(Query))
2. Authorization (authorize(HttpServletRequest)
3. Execution (execute()
4. Logging (emitLogsAndMetrics(Throwable, String, long)

This object is not thread-safe.

Constructor Summary

Constructors

Constructor

Description

QueryLifecycle(org.apache.druid.query.QueryToolChestWarehouse warehouse, org.apache.druid.query.QuerySegmentWalker texasRanger, org.apache.druid.query.GenericQueryMetricsFactory queryMetricsFactory, org.apache.druid.java.util.emitter.service.ServiceEmitter emitter, RequestLogger requestLogger, AuthorizerMapper authorizerMapper, org.apache.druid.query.DefaultQueryConfig defaultQueryConfig, AuthConfig authConfig, long startMs, long startNs)

Method Summary

Modifier and Type	Method	Description
Access	authorize(javax.servlet.http.HttpServletRequest req)	Authorize the query.
Access	authorize(AuthenticationResult authenticationResult)	Authorize the query using the authentication result.
void	emitLogsAndMetrics(Throwable e, String remoteAddress, long bytesWritten)	Emit logs and metrics for this query.
<T> QueryResponse<T>	execute()	Execute the query.
org.apache.druid.query.Query<?>	getQuery()
String	getQueryId()
org.apache.druid.query.QueryToolChest	getToolChest()
void	initialize(org.apache.druid.query.Query<?> baseQuery)	Initializes this object to execute a specific query.
com.fasterxml.jackson.databind.ObjectWriter	newOutputWriter(QueryResource.ResourceIOReaderWriter ioReaderWriter)
<T> QueryResponse<T>	runSimple(org.apache.druid.query.Query<T> query, AuthenticationResult authenticationResult, Access authorizationResult)	For callers who have already authorized their query, and where simplicity is desired over flexibility.
String	threadName(String currThreadName)

Methods inherited from class java.lang.Object

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

Constructor Detail

QueryLifecycle

public QueryLifecycle(org.apache.druid.query.QueryToolChestWarehouse warehouse,
                      org.apache.druid.query.QuerySegmentWalker texasRanger,
                      org.apache.druid.query.GenericQueryMetricsFactory queryMetricsFactory,
                      org.apache.druid.java.util.emitter.service.ServiceEmitter emitter,
                      RequestLogger requestLogger,
                      AuthorizerMapper authorizerMapper,
                      org.apache.druid.query.DefaultQueryConfig defaultQueryConfig,
                      AuthConfig authConfig,
                      long startMs,
                      long startNs)

Method Detail

runSimple

public <T> QueryResponse<T> runSimple(org.apache.druid.query.Query<T> query,
                                      AuthenticationResult authenticationResult,
                                      Access authorizationResult)

For callers who have already authorized their query, and where simplicity is desired over flexibility. This method does it all in one call. Logs and metrics are emitted when the Sequence is either fully iterated or throws an exception.

Parameters:

query - the query

authenticationResult - authentication result indicating identity of the requester

authorizationResult - authorization result of requester

Returns:

results

initialize

public void initialize(org.apache.druid.query.Query<?> baseQuery)

Initializes this object to execute a specific query. Does not actually execute the query.

Parameters:

baseQuery - the query

authorize

public Access authorize(javax.servlet.http.HttpServletRequest req)

Authorize the query. Will return an Access object denoting whether the query is authorized or not.

Parameters:

req - HTTP request object of the request. If provided, the auth-related fields in the HTTP request will be automatically set.

Returns:

authorization result

authorize

public Access authorize(AuthenticationResult authenticationResult)

Authorize the query using the authentication result. Will return an Access object denoting whether the query is authorized or not. This method is to be used by the grpc-query-extension.

Parameters:

authenticationResult - authentication result indicating identity of the requester

Returns:

authorization result of requester

execute

public <T> QueryResponse<T> execute()

Execute the query. Can only be called if the query has been authorized. Note that query logs and metrics will not be emitted automatically when the Sequence is fully iterated. It is the caller's responsibility to call emitLogsAndMetrics(Throwable, String, long) to emit logs and metrics.

Returns:

result sequence and response context

emitLogsAndMetrics

public void emitLogsAndMetrics(@Nullable
                               Throwable e,
                               @Nullable
                               String remoteAddress,
                               long bytesWritten)

Emit logs and metrics for this query.

Parameters:

e - exception that occurred while processing this query

remoteAddress - remote address, for logging; or null if unknown

bytesWritten - number of bytes written; will become a query/bytes metric if >= 0

getQuery

@Nullable
public org.apache.druid.query.Query<?> getQuery()

getQueryId

public String getQueryId()

threadName

public String threadName(String currThreadName)

newOutputWriter

public com.fasterxml.jackson.databind.ObjectWriter newOutputWriter(QueryResource.ResourceIOReaderWriter ioReaderWriter)

getToolChest

public org.apache.druid.query.QueryToolChest getToolChest()