org.apache.lens.server.api.driver.hooks

Class UserBasedQueryHook

java.lang.Object

org.apache.lens.server.api.driver.hooks.NoOpDriverQueryHook

org.apache.lens.server.api.driver.hooks.UserBasedQueryHook

All Implemented Interfaces:

DriverQueryHook

public class UserBasedQueryHook
extends NoOpDriverQueryHook

This hook allows for a driver to discard queries based on the submitter of the query. This works on two configurations values, among which either or none can be set. The configuration values are picked from driver configuration. The driver config can set `allowed.users` as a comma separated list of users that are allowed to submit queries on this driver. Queries from only those users will be allowed and the rest will be discarded. On the other hand, the driver can set `disallowed.users` as a comma separated list of users that are disallowed to submit queries on this driver. Queries from these users will be rejected, while queries from any other user will be accepted.

Field Summary

Fields

Modifier and Type	Field and Description
static String	ALLOWED_USERS
static String	DISALLOWED_USERS

Constructor Summary

Constructors

Constructor and Description
UserBasedQueryHook()

Method Summary

Modifier and Type	Method and Description
void	preRewrite(AbstractQueryContext ctx) Called just before rewrite operation is tried on this driver
void	setDriver(LensDriver driver) This setter method is called by the driver once hook instance is created.

Methods inherited from class org.apache.lens.server.api.driver.hooks.NoOpDriverQueryHook

getDriver, postDriverSelection, postEstimate, postRewrite, preEstimate, preLaunch

Methods inherited from class java.lang.Object

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

Field Detail

ALLOWED_USERS

public static final String ALLOWED_USERS

See Also:

Constant Field Values

DISALLOWED_USERS

public static final String DISALLOWED_USERS

See Also:

Constant Field Values

Constructor Detail

UserBasedQueryHook

public UserBasedQueryHook()

Method Detail

setDriver

public void setDriver(LensDriver driver)

Description copied from interface: DriverQueryHook

This setter method is called by the driver once hook instance is created. This driver information can be used while extracting driver specific information form the QueryContext.

Specified by:

setDriver in interface DriverQueryHook

Overrides:

setDriver in class NoOpDriverQueryHook

preRewrite

public void preRewrite(AbstractQueryContext ctx)
                throws LensException

Description copied from interface: DriverQueryHook

Called just before rewrite operation is tried on this driver

Specified by:

preRewrite in interface DriverQueryHook

Overrides:

preRewrite in class NoOpDriverQueryHook

Throws:

LensException