KsqlResource¶

KsqlResource is used by KsqlRestApplication to execute statements (indirectly using KsqlServerEndpoints).

Creating Instance¶

KsqlResource takes the following to be created:

• KsqlEngine
• CommandRunner
• ksql.server.command.response.timeout.ms
• ActivenessRegistrar
• Injector factory
• KsqlAuthorizationValidator
• Errors Handlers
• DenyListPropertyValidator
• CommandRunner warning message

KsqlResource is created when:

• KsqlRestApplication utility is used to build a KsqlRestApplication (and creates a KsqlRestApplication)

CommandRunner¶

KsqlResource is given a CommandRunner when created.

The CommandRunner is used only to access the CommandQueue when:

• configure (to create a DistributingExecutor and a DefaultCommandQueueSync for RequestHandler)
• handleKsqlStatements (to httpWaitForCommandSequenceNumber)

configure¶

void configure(
  KsqlConfig config)

configure is part of the KsqlConfigurable abstraction.

configure...FIXME

shouldSynchronize¶

boolean shouldSynchronize(
  Class<? extends Statement> statementClass)

shouldSynchronize is true when the given statementClass is as follows:

1. Not in SYNC_BLACKLIST
2. In EXECUTOR_MAP

shouldSynchronize is used when:

• KsqlResource is requested to configure (and creates a DefaultCommandQueueSync for the RequestHandler)

SYNC_BLACKLIST¶

• ListTopics
• ListFunctions
• DescribeFunction
• ListProperties
• SetProperty
• UnsetProperty

RequestHandler¶

KsqlResource creates a RequestHandler when requested to configure.

RequestHandler is used when:

• terminateCluster
• handleKsqlStatements

Handling KSQL Statements¶

EndpointResponse handleKsqlStatements(
  KsqlSecurityContext securityContext,
  KsqlRequest request)

handleKsqlStatements prints out the following INFO message to the logs:

Received: [request]

handleKsqlStatements requests the KsqlEngine to parse the KSQL text (from the given KsqlRequest).

handleKsqlStatements requests the RequestValidator to validate the statements (in a SandboxedServiceContext).

handleKsqlStatements requests the RequestHandler to execute the KSQL statements.

In the end, handleKsqlStatements prints out the following INFO message to the logs:

Processed successfully: [request]

handleKsqlStatements is used when:

• KsqlServerEndpoints is requested to execute a KsqlRequest
• ServerInternalKsqlClient is requested to makeKsqlRequest

Logging¶

Enable ALL logging level for io.confluent.ksql.rest.server.resources.KsqlResource logger to see what happens inside.

Add the following line to log4j.properties:

log4j.logger.io.confluent.ksql.rest.server.resources.KsqlResource=ALL

Refer to Logging.