lens-server/src/main/resources/lensserver-default.xml

<?xml version="1.0"?>
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<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>

<configuration>
  <property>
    <name>lens.server.drivers</name>
    <value>hive:org.apache.lens.driver.hive.HiveDriver</value>
    <description>Drivers enabled for this lens server instance</description>
  </property>

  <property>
    <name>lens.server.driver.selector.class</name>
    <value>org.apache.lens.server.api.driver.MinQueryCostSelector</value>
    <description>Class for selecting best driver given the query context</description>
  </property>

  <property>
    <name>lens.server.query.acceptors</name>
    <value></value>
    <description>Query Acceptors configured. Query acceptors are consulted first, before anything happens for the
      given query. They can either return null or return a messaging indicating why the given query shouldn't be
      accepted. These can be used to filter out queries at the earliest.
    </description>
  </property>

  <property>
    <name>lens.server.query.phase1.rewriters</name>
    <value></value>
    <description>Query phase 1 rewriters. This is to convert user query to cube query. The resulting cube query will
      be passed for validation and rewriting to hql query.\
      Use cases will be to use extra intelligence to convert user query to optimized cube query.\
      Or define shortcuts for certain frequently used queries :)
    </description>
  </property>

  <property>
    <name>lens.server.servicenames</name>
    <value>session,alarm,query,savedquery,metastore,scheduler,quota</value>
    <description>These services would be started in the specified order when lens-server starts up</description>
  </property>

  <property>
    <name>lens.server.session.service.impl</name>
    <value>org.apache.lens.server.session.HiveSessionService</value>
    <description>Implementation class for session service</description>
  </property>

  <property>
    <name>lens.server.query.service.impl</name>
    <value>org.apache.lens.server.query.QueryExecutionServiceImpl</value>
    <description>Implementation class for query execution service</description>
  </property>

  <property>
    <name>lens.server.savedquery.service.impl</name>
    <value>org.apache.lens.server.query.save.SavedQueryServiceImpl</value>
    <description>Implementation class for saved query service</description>
  </property>

  <property>
    <name>lens.server.quota.service.impl</name>
    <value>org.apache.lens.server.quota.QuotaServiceImpl</value>
    <description>Implementation class for quota service</description>
  </property>

  <property>
    <name>lens.server.metastore.service.impl</name>
    <value>org.apache.lens.server.metastore.CubeMetastoreServiceImpl</value>
    <description>Implementation class for metastore service</description>
  </property>

  <property>
    <name>lens.server.alarm.service.impl</name>
    <value>org.apache.lens.server.scheduler.AlarmService</value>
    <description>Implementation class for alarm service</description>
  </property>

  <property>
    <name>lens.server.scheduler.service.impl</name>
    <value>org.apache.lens.server.scheduler.SchedulerServiceImpl</value>
    <description>Implementation class for query scheduler service</description>
  </property>

  <property>
    <name>lens.server.base.url</name>
    <value>http://0.0.0.0:9999/lensapi/</value>
    <description>The base url for the lens server</description>
  </property>

  <property>
    <name>lens.server.query.state.logger.enabled</name>
    <value>true</value>
    <description>Disable or enable the query state logger with this config.
      The location for the logger can be specified in logback xml for the class
      org.apache.lens.server.query.QueryExecutionServiceImpl.QueryStatusLogger
    </description>
  </property>

  <property>
    <name>lens.server.event.service.thread.pool.size</name>
    <value></value>
    <description>The size of thread pool for notifying events. The no value is specified,
      it uses the available processors as the number.
    </description>
  </property>

  <property>
    <name>lens.server.enable.console.metrics</name>
    <value>false</value>
    <description>Enable metrics to be reported on console</description>
  </property>

  <property>
    <name>lens.server.enable.csv.metrics</name>
    <value>false</value>
    <description>Enable metrics to be reported as csv files in a directory</description>
  </property>

  <property>
    <name>lens.server.metrics.csv.directory.path</name>
    <value>metrics/</value>
    <description>Path of the directory in which to report metrics as separate csv files. </description>
  </property>

  <property>
    <name>lens.server.enable.ganglia.metrics</name>
    <value>false</value>
    <description>Enable metrics to be reported on ganglia</description>
  </property>

  <property>
    <name>lens.server.metrics.ganglia.host</name>
    <value></value>
    <description>The ganglia host name</description>
  </property>

  <property>
    <name>lens.server.metrics.ganglia.port</name>
    <value></value>
    <description>The ganglia port</description>
  </property>

  <property>
    <name>lens.server.enable.graphite.metrics</name>
    <value>false</value>
    <description>Enable metrics to be reported on graphite</description>
  </property>

  <property>
    <name>lens.server.metrics.graphite.host</name>
    <value></value>
    <description>The graphite host name</description>
  </property>

  <property>
    <name>lens.server.metrics.graphite.port</name>
    <value></value>
    <description>The graphite port</description>
  </property>

  <property>
    <name>lens.server.enable.resource.method.metering</name>
    <value>false</value>
    <description>Whether to Enable metering for all resource methods.</description>
  </property>

  <property>
    <name>lens.server.metrics.reporting.period</name>
    <value>10</value>
    <description>The reporting period for metrics. The value is in seconds</description>
  </property>

  <property>
    <name>lens.server.state.persistence.enabled</name>
    <value>true</value>
    <description>If flag is enabled, state of all the services will be persisted periodically to a location
      specified by lens.server.persist.location and on server restart all the services will be started
      from last saved state.
    </description>
  </property>

  <property>
    <name>lens.server.state.persistence.interval.millis</name>
    <value>300000</value>
    <description>Lens server state persistence time interval in milliseconds</description>
  </property>

  <property>
    <name>lens.server.persist.location</name>
    <value>file:///tmp/lensserver</value>
    <description>The directory in which lens server will persist its state when it is
      going down. The location be on any Hadoop compatible file system. Server will read from
      the location when it is restarted and recovery is enabled. So, Server should have
      both read and write permissions to the location
    </description>
  </property>

  <property>
    <name>lens.server.mode</name>
    <value>OPEN</value>
    <description>The mode in which server should run. Allowed values are OPEN, READ_ONLY,
      METASTORE_READONLY, METASTORE_NODROP. OPEN mode will allow all requests. READ_ONLY mode
      will allow all requests on session resouce and only GET requests on all other resources.
      METASTORE_READONLY will allow GET on metastore and all other requests in other services.
      METASTORE_NODROP will not allow DELETE on metastore, will allow all other requests.
    </description>
  </property>

  <property>
    <name>lens.server.session.timeout.seconds</name>
    <value>86400</value>
    <description>Lens session timeout in seconds.If there is no activity on
      the session for this period then the session will be closed.Default timeout is one day.
    </description>
  </property>

  <property>
    <name>lens.server.statistics.store.class</name>
    <value>org.apache.lens.server.stats.store.log.LogStatisticsStore</value>
    <description>Default implementation of class used to persist Lens Statistics.</description>
  </property>

  <property>
    <name>lens.server.statistics.log.rollover.interval</name>
    <value>3600000</value>
    <description>Default rate which log statistics store scans for rollups in milliseconds.</description>
  </property>

  <property>
    <name>lens.server.statistics.warehouse.dir</name>
    <value>file:///tmp/lens/statistics/warehouse</value>
    <description>Default top level location where stats are moved by the log statistics store.</description>
  </property>

  <property>
    <name>lens.server.statistics.db</name>
    <value>lensstats</value>
    <description>Database to which statistics tables are created and partitions are added.</description>
  </property>

  <!-- Query Result Purger Configurations -->
  <property>
    <name>lens.server.resultset.purge.enabled</name>
    <value>false</value>
    <description>Whether to purge the query results </description>
  </property>

  <property>
    <name>lens.server.resultsetpurger.sleep.interval.secs</name>
    <value>3600</value>
    <description>Periodicity for Query result purger runs. Default 1 hour. </description>
  </property>

  <property>
    <name>lens.server.query.resultset.retention</name>
    <value>1 day</value>
    <description>Lens query resultset retention period. Default 1 day </description>
  </property>

  <property>
    <name>lens.server.hdfs.output.retention</name>
    <value>1 day</value>
    <description>hdfs output retention period. Default 1 day</description>
  </property>

  <!-- Finished Query Purging Configurations -->
  <property>
    <name>lens.server.querypurger.sleep.interval</name>
    <value>10000</value>
    <description>The interval(milliseconds) with which purger to run periodically. Default 10 sec. </description>
  </property>

  <property>
    <name>lens.server.query.expiry.check.interval.millis</name>
    <value>60000</value>
    <description>The interval(milliseconds) with which query expiry will run periodically. Default is 1 minute. The
      value needs to be much lower than lens.query.timeout.millis. If the final deployment values of query timeout
      can be smaller, then reduce this value to be much lower.
    </description>
  </property>
  <property>
    <name>lens.server.inmemory.resultset.ttl.secs</name>
    <value>300</value>
    <description>This property defines the TTL(time to live) in seconds for all result sets of type InMemoryResultSet
     beyond which they are eligible for purging irrespective of whether the result set has been read or not.
     The default value is 300 seconds (5 minutes).
     </description>
  </property>

  <property>
    <name>lens.server.domain</name>
    <value>company.com</value>
    <description>Server domain. This will be used in authentication and Sending emails to users.
      For the server, the username will be without domain and domain will come through conf.
    </description>
  </property>
  <property>
    <name>lens.server.db.driver.name</name>
    <value>org.hsqldb.jdbcDriver</value>
    <description>Database driver for database where Finished queries have to be stored.
      Also used for database based user config loaders
    </description>
  </property>
  <property>
    <name>lens.server.db.jdbc.url</name>
    <value>jdbc:hsqldb:/tmp/lensserver/queries.db</value>
    <description>JDBC URL where the database for storing finished queries is located.
      Also used for database based user config loaders
    </description>
  </property>
  <property>
    <name>lens.server.db.jdbc.user</name>
    <value>SA</value>
    <description>JDBC User for Finished queries table. Also used for database based user config loaders</description>
  </property>
  <property>
    <name>lens.server.db.jdbc.pass</name>
    <value></value>
    <description>JDBC Password for Finished queries table. Also used for database based user config loaders
    </description>
  </property>
  <property>
    <name>lens.server.db.validation.query</name>
    <value>select 1 from INFORMATION_SCHEMA.SYSTEM_USERS</value>
    <description>BasicDatasource has a config parameter called validationQuery. This query is run before passing
      the Datasource to the application to verify if connection is valid.\
      {{{http://commons.apache.org/proper/commons-dbcp/configuration.html}dbcp configuration}} \
      {{{http://stackoverflow.com/questions/10684244/dbcp-validationquery-for-different-databases}validationquery for different databases}} \
    </description>
  </property>

  <property>
    <name>lens.server.mail.from.address</name>
    <value>blah@company.com</value>
    <description>The from field in the notifier mail to the submitter.</description>
  </property>

  <property>
    <name>lens.server.mail.host</name>
    <value>mail-host.company.com</value>
    <description>SMTP Host for sending mail</description>
  </property>

  <property>
    <name>lens.server.mail.port</name>
    <value>25</value>
    <description>SMTP Port</description>
  </property>

  <property>
    <name>lens.server.mail.smtp.timeout</name>
    <value>30000</value>
    <description>Socket read timeout value in milliseconds. This timeout is implemented by java.net.Socket. Default is
      30 seconds.
    </description>
  </property>

  <property>
    <name>lens.server.mail.smtp.connectiontimeout</name>
    <value>15000</value>
    <description>Socket connection timeout value in milliseconds. This timeout is implemented by java.net.Socket.
      Default is 15 seconds.
    </description>
  </property>

  <property>
    <name>lens.server.ws.resourcenames</name>
    <value>session,metastore,query,savedquery,quota,scheduler,index,log</value>
    <description>These JAX-RS resources would be started in the specified order when lens-server starts up</description>
  </property>

  <property>
    <name>lens.server.session.ws.resource.impl</name>
    <value>org.apache.lens.server.session.SessionResource</value>
    <description>Implementation class for Session Resource</description>
  </property>

  <property>
    <name>lens.server.savedquery.ws.resource.impl</name>
    <value>org.apache.lens.server.query.save.SavedQueryResource</value>
    <description>Implementation class for Saved query Resource</description>
  </property>

  <property>
    <name>lens.server.query.ws.resource.impl</name>
    <value>org.apache.lens.server.query.QueryServiceResource</value>
    <description>Implementation class for Query Resource</description>
  </property>

  <property>
    <name>lens.server.quota.ws.resource.impl</name>
    <value>org.apache.lens.server.quota.QuotaResource</value>
    <description>Implementation class for Quota Resource</description>
  </property>

  <property>
    <name>lens.server.index.ws.resource.impl</name>
    <value>org.apache.lens.server.IndexResource</value>
    <description>Implementation class for Index Resource</description>
  </property>

  <property>
    <name>lens.server.log.ws.resource.impl</name>
    <value>org.apache.lens.server.LogResource</value>
    <description>Implementation class for Log Resource</description>
  </property>

  <property>
    <name>lens.server.metastore.ws.resource.impl</name>
    <value>org.apache.lens.server.metastore.MetastoreResource</value>
    <description>Implementation class for Metastore Resource</description>
  </property>

  <property>
    <name>lens.server.scheduler.ws.resource.impl</name>
    <value>org.apache.lens.server.scheduler.ScheduleResource</value>
    <description>Implementation class for query scheduler resource</description>
  </property>

  <property>
    <name>lens.server.ws.featurenames</name>
    <value>multipart,moxyjson,moxyjsonconfigresovler</value>
    <description>These JAX-RS Feature(s) would be started in the specified order when lens-server starts up
    </description>
  </property>

  <property>
    <name>lens.server.multipart.ws.feature.impl</name>
    <value>org.glassfish.jersey.media.multipart.MultiPartFeature</value>
    <description>Implementation class for query scheduler resource</description>
  </property>

  <property>
    <name>lens.server.moxyjson.ws.feature.impl</name>
    <value>org.glassfish.jersey.moxy.json.MoxyJsonFeature</value>
    <description>Enable Moxy json feature </description>
  </property>
  <property>
    <name>lens.server.moxyjsonconfigresovler.ws.feature.impl</name>
    <value>org.apache.lens.api.util.MoxyJsonConfigurationContextResolver</value>
    <description>Moxy json configuration resolver</description>
  </property>
  <property>
    <name>lens.server.ws.filternames</name>
    <value>requestlogger,consistentState,serverMode</value>
    <description>These JAX-RS filters would be started in the specified order when lens-server starts up</description>
  </property>

  <property>
    <name>lens.server.requestlogger.ws.filter.impl</name>
    <value>org.apache.lens.server.LensRequestLoggingFilter</value>
    <description>Implementation class for Request logging Filter</description>
  </property>

  <property>
    <name>lens.server.consistentState.ws.filter.impl</name>
    <value>org.apache.lens.server.ConsistentStateFilter</value>
    <description>Implementation class for ConsistentState Filter</description>
  </property>

  <property>
    <name>lens.server.serverMode.ws.filter.impl</name>
    <value>org.apache.lens.server.ServerModeFilter</value>
    <description>Implementation class for ServerMode Filter</description>
  </property>

  <property>
    <name>lens.server.ws.listenernames</name>
    <value>appevent</value>
    <description>These listeners would be called in the specified order when lens-server starts up</description>
  </property>

  <property>
    <name>lens.server.appevent.ws.listener.impl</name>
    <value>org.apache.lens.server.LensApplicationListener</value>
    <description>Implementation class for Lens Application Listener</description>
  </property>

  <!-- CLI service properties which can be overriden for LENS services -->

  <property>
    <name>hive.server2.idle.session.timeout</name>
    <value>0</value>
    <description>Session should be closed by lens. There would be a mismatch when hive has closed session due to timeout
    and lens is not aware of that.</description>
  </property>
    <property>
    <name>hive.server2.idle.operation.timeout</name>
    <value>0</value>
    <description>Closing of operations should be handled by lens. Hive should not invalidate operations upon timeout
    </description>
  </property>
  <property>
    <name>hive.server2.async.exec.threads</name>
    <value>5</value>
    <description>Number of threads required in async thread pool for query execution in the lens directly. Lens uses
      query execution directly only to add and delete resources, which are mostly synchronous. So keeping to a lower
      value.
    </description>
  </property>

  <property>
    <name>hive.server2.log.redirection.enabled</name>
    <value>false</value>
    <description>Disable the log direction on the lens server sessions. There are no logs required for each session in
      lens sessions. This will decrease number of file handles associated to lens server.
    </description>
  </property>

  <property>
    <name>hive.server2.logging.operation.enabled</name>
    <value>false</value>
    <description>Disable the operation logging, since there are no execution operation happening in lens session.
      Keeping it true might conflict with Hive Server if both are running on the same machine causing disappearance
      of the operation log directory.
    </description>
  </property>

  <property>
    <name>hive.server2.authentication</name>
    <value>NONE</value>
    <description>
      Client authentication types.
      NONE: no authentication check
      LDAP: LDAP/AD based authentication
      KERBEROS: Kerberos/GSSAPI authentication
      CUSTOM: Custom authentication provider
      (Use with property hive.server2.custom.authentication.class)
      PAM: Pluggable authentication module.
    </description>
  </property>

  <property>
    <name>hive.server2.authentication.ldap.url</name>
    <value></value>
    <description>
      LDAP connection URL
    </description>
  </property>

  <property>
    <name>hive.server2.authentication.ldap.security.protocol</name>
    <value>ssl</value>
    <description>
      Its value is a string determined by the service provider (e.g. "ssl").
      If this property is unspecified, the behaviour is determined by the service provider.
      It's value will be directly passed as "java.naming.security.protocol"
    </description>
  </property>

  <property>
    <name>hive.server2.authentication.ldap.baseDN</name>
    <value></value>
    <description>
      LDAP base DN
    </description>
  </property>

  <property>
    <name>hive.server2.authentication.ldap.Domain</name>
    <value></value>
    <description>
      The ldap domin
    </description>
  </property>

  <property>
    <name>lens.server.user.resolver.type</name>
    <value>FIXED</value>
    <description>Type of user config resolver. allowed values are FIXED, PROPERTYBASED, DATABASE, LDAP_BACKED_DATABASE,
      CUSTOM.
    </description>
  </property>

  <property>
    <name>lens.server.user.group.type</name>
    <value>FIXED</value>
    <description>Type of user group config resolver. allowed values are FIXED, CUSTOM.
    </description>
  </property>

  <property>
    <name>lens.server.user.resolver.fixed.value</name>
    <value></value>
    <description>Required for FIXED user resolver.
      when lens.server.user.resolver.type=FIXED, This will be the value cluster user will resolve to.
    </description>
  </property>


  <property>
    <name>lens.server.user.group.fixed.value</name>
    <value>test</value>
    <description>Required for FIXED user group resolver.
      when lens.server.user.group.type=FIXED, This will be the value user groups will resolve to.
    </description>
  </property>

  <property>
    <name>lens.server.user.resolver.propertybased.filename</name>
    <value>/path/to/propertyfile</value>
    <description>Required for PROPERTYBASED user resolver.
      when lens.server.user.resolver.type is PROPERTYBASED, then this file will be read and parsed to
      determine cluster user. Each line should contain username followed by DOT followed by property full name
      followed by equal-to sign and followed by value.
      example schema of the file is:
      user1.lens.server.cluster.user=clusteruser1
      user1.mapred.job.queue.name=queue1
      *.lens.server.cluster.user=defaultclusteruser
      *.mapred.job.queue.name=default
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.custom.class</name>
    <value>full.package.name.Classname</value>
    <description>Required for CUSTOM user resolver.
      In case the provided implementations are not sufficient for user config resolver,
      a custom classname can be provided. Class should extend org.apache.lens.server.user.UserConfigLoader
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.db.keys</name>
    <value>lens.session.cluster.user,mapred.job.queue.name</value>
    <description>Required for DATABASE and LDAP_BACKED_DATABASE user resolvers.
      For database based user config loaders, the conf keys that will be loaded from database.
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.db.query</name>
    <value>select clusteruser,queue from user_config_table where username=?</value>
    <description>Required for DATABASE and LDAP_BACKED_DATABASE user resolvers.
      For database based user config loader, this query will be run with single argument = logged in user
      and the result columns will be assigned to lens.server.user.resolver.db.keys in order.
      For ldap backed database resolver, the argument to this query will be the intermediate values obtained from ldap.
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.ldap.intermediate.db.query</name>
    <value>select department from user_department where username=? and expiry>?</value>
    <description>Required for LDAP_BACKED_DATABASE user resolvers.
      query to obtain intermediate values from database backing ldap as cache.
      two arguments: logged in user and current time.
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.ldap.intermediate.db.delete.sql</name>
    <value>delete from user_department where username=?</value>
    <description>Required for LDAP_BACKED_DATABASE user resolvers.
      query to delete intermediate values from database backing ldap as cache.
      one argument: logged in user.
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.ldap.intermediate.db.insert.sql</name>
    <value>insert into user_department (username, department, expiry) values (?, ?, ?)</value>
    <description>Required for LDAP_BACKED_DATABASE user resolvers.
      query to insert intermediate values from database backing ldap as cache.
      arguments: first logged in user, then all intermediate values, then current time + expiration time
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.ldap.fields</name>
    <value>department</value>
    <description>Required for LDAP_BACKED_DATABASE user resolvers.
      list of fields to be obtained from ldap. These will be cached by the intermediate db.
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.ldap.bind.dn</name>
    <value></value>
    <description>Required for LDAP_BACKED_DATABASE user resolvers.
      ldap dn for admin binding
      example: CN=company-it-admin,ou=service-account,ou=company-service-account,dc=dc1,dc=com...
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.ldap.bind.password</name>
    <value></value>
    <description>Required for LDAP_BACKED_DATABASE user resolvers.
      ldap password for admin binding above
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.ldap.search.base</name>
    <value></value>
    <description>Required for LDAP_BACKED_DATABASE user resolvers.
      for searching intermediate values for a user, the search keys.
      example: cn=users,dc=dc1,dc=dc2...
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.ldap.search.filter</name>
    <value>(&amp;(objectClass=user)(sAMAccountName=%s))</value>
    <description>Required for LDAP_BACKED_DATABASE user resolvers.
      filter pattern for ldap search
    </description>
  </property>
  <property>
    <name>lens.server.user.resolver.ldap.url</name>
    <value></value>
    <description>Required for LDAP_BACKED_DATABASE user resolvers.
      ldap url to connect to.
    </description>
  </property>

  <property>
    <name>lens.server.service.provider.factory</name>
    <value>org.apache.lens.server.ServiceProviderFactoryImpl</value>
    <final>true</final>
    <description>Service provider factory implementation class. This parameter is used
      to lookup the factory implementation class name that would provide an
      instance of ServiceProvider. Users should instantiate the class to obtain its instance.

      Example
      --
      Class spfClass
      = conf.getClass("lens.server.service.provider.factory",
      null, ServiceProviderFactory.class);

      ServiceProviderFactory spf = spfClass.newInstance();
      ServiceProvider serviceProvider = spf.getServiceProvider();
      --
      This is not supposed to be overridden by users.
    </description>
  </property>

  <property>
    <name>lens.server.state.persist.out.stream.buffer.size</name>
    <value>1048576</value>
    <description>Output Stream Buffer Size used in writing lens server state to file system. Size is in bytes.</description>
  </property>

  <property>
    <name>lens.server.database.resource.dir</name>
    <value>/tmp/lens/resources</value>
    <description>Top level directory to store database specific static resources which are added to each database.
    To add a static resource for a DB, create a directory with the same name as that of the DB under this directory, and
    place the resources inside the DB directory. Any subdirectories under the DB directory and the resources under them
    will be ignored</description>
  </property>

  <property>
    <name>lens.server.estimate.timeout.millis</name>
    <value>300000</value>
    <description>Timeout for parallel query estimate calls in milliseconds.
      A driver needs to comeback with a query estimate within this timeout. If the timeout is reached, only the drivers
      that have provided an estimate would be considered for query selection. If the timeout is reached and none
      of the drivers have provided an estimate then estimate calls fails with an exception.
    </description>
  </property>

  <property>
    <name>lens.server.estimate.pool.min.threads</name>
    <value>3</value>
    <description>Minimum number of threads in the estimate thread pool</description>
  </property>

  <property>
    <name>lens.server.estimate.pool.max.threads</name>
    <value>100</value>
    <description>Maximum number of threads in the estimate thread pool</description>
  </property>

  <property>
    <name>lens.server.estimate.pool.keepalive.millis</name>
    <value>60000</value>
    <description>Thread keep alive time in milliseconds for the estimate thread pool.
      If there are no estimate requests for this period,then cached threads are released from the pool.
    </description>
  </property>

  <property>
    <name>lens.server.launcher.pool.min.threads</name>
    <value>3</value>
    <description>Minimum number of threads in the query launcher thread pool</description>
  </property>

  <property>
    <name>lens.server.launcher.pool.max.threads</name>
    <value>100</value>
    <description>Maximum number of threads in the query launcher thread pool. Keeping the default to hundred, we may
      never grow till there, it would go to max for concurrrent queries allowed on all drivers together.
      This value should be greater than the max concurrent queries allowed on all drivers. </description>
  </property>

  <property>
    <name>lens.server.launcher.pool.keepalive.millis</name>
    <value>60000</value>
    <description>Thread keep alive time in milliseconds for the query launcher thread pool.
      If there are no query launches for this period,then cached threads will be released from the pool.
    </description>
  </property>

  <property>
    <name>lens.server.session.expiry.service.interval.secs</name>
    <value>3600</value>
    <description>Interval at which lens session expiry service runs</description>
  </property>

  <property>
    <name>lens.server.scheduling.queue.poll.interval.millisec</name>
    <value>2000</value>
    <description>The interval at which submission thread will poll scheduling queue to fetch the next query for
      submission. If value is less than equal to 0, then it would mean that thread will continuosly poll without
      sleeping. The interval has to be given in milliseconds.</description>
  </property>

  <property>
    <name>lens.server.query.launching.constraint.factories</name>
    <value>org.apache.lens.server.query.constraint.TotalQueryCostCeilingConstraintFactory</value>
    <description>Factories used to instantiate constraints enforced on queries by lens. Every Factory should be an
      implementation of org.apache.lens.server.api.common.ConfigBasedObjectCreationFactory and create an implementation
      of org.apache.lens.server.api.query.constraint.QueryLaunchingConstraint. A query will be launched only if all
      constraints pass.</description>
  </property>

  <property>
    <name>lens.server.total.query.cost.ceiling.per.user</name>
    <value>-1.0</value>
    <description>A query submitted by user will be launched only if total query cost of all current
      launched queries of user is less than or equal to total query cost ceiling defined by this property.
      This configuration value is only useful when TotalQueryCostCeilingConstraint is enabled by using
      org.apache.lens.server.query.constraint.TotalQueryCostCeilingConstraintFactory as one of the factories in
      lens.server.query.constraint.factories property. Default is -1.0 which means that there is no limit on the total
      query cost of launched queries submitted by a user.</description>
  </property>

  <property>
    <name>lens.server.waiting.queries.selection.policy.factories</name>
    <value>org.apache.lens.server.query.collect.UserSpecificWaitingQueriesSelectionPolicyFactory</value>
    <description>Factories used to instantiate waiting queries selection policies. Every factory should
      be an implementation of org.apache.lens.server.api.common.ConfigBasedObjectCreationFactory and create an
      implementation of org.apache.lens.server.api.query.collect.WaitingQueriesSelectionPolicy.</description>
  </property>

  <property>
    <name>lens.server.savedquery.jdbc.dialectclass</name>
    <value>org.apache.lens.server.query.save.SavedQueryDao$HSQLDialect</value>
    <description>Dialect of the target DB, Default is HSQL. Override with the target DB used.</description>
  </property>

  <property>
    <name>lens.server.savedquery.list.default.offset</name>
    <value>0</value>
    <description>Key denoting the default start value of saved query list api.</description>
  </property>
  <property>
    <name>lens.server.savedquery.list.default.count</name>
    <value>20</value>
    <description>Key denoting the default fetch value of saved query list api.</description>
  </property>
  <property>
    <name>lens.server.max.sessions.per.user</name>
    <value>10</value>
    <description>Number of sessions can be allowed for each user.
      User has to close one of the active sessions to open a new session once limit is reached. Otherwise Server throws
      an exception by saying that opened session limit has been already reached for user.
    </description>
  </property>
  <property>
    <name>lens.server.status.update.num.retries</name>
    <value>10</value>
    <description>The number of retries a status update will tried with exponentital back off, in case of transient
      issues, upon which query will be marked FAILED.
    </description>
  </property>
  <property>
    <name>lens.server.status.update.maximum.delay.secs</name>
    <value>1800</value>
    <description>The maximum delay in seconds for next status update to happen after any transient failure. This will
      be used a maximum delay sothat exponential wait times not to grow to bigger value.
    </description>
  </property>
  <property>
    <name>lens.server.duplicate.query.allowed</name>
    <value>false</value>
    <description>If this is false and same query is submitted by a user in the same session
      and with the same configuration while earlier query is not completed then
      lens server will return the handle of the previous query
    </description>
  </property>
   <property>
    <name>lens.server.scheduler.store.class</name>
    <value>org.apache.lens.server.scheduler.SchedulerDAO$SchedulerHsqlDBStore</value>
    <description>A subclass of SchedulerDBStore class used for storing scheduler related information.
    </description>
  </property>
  <property>
    <name>lens.server.status.update.exponential.wait.millis</name>
    <value>30000</value>
    <description>Number of millis that would grow exponentially for next update, incase of transient failures.
    </description>
  </property>
  <property>
    <name>lens.query.current.time.millis</name>
    <value>0</value>
    <description>Query current time in millis. This is used to resolve 'now'. If value is set to zero, 'now' is
     resolved to current value</description>
  </property>

  <property>
    <name>lens.server.http.notification.conn.timeout.millis</name>
    <value>5000</value>
    <description>This is the connection timeout for all HTTP Notifications sent by lens server.
      Default connection timeout is 5 secs</description>
  </property>
  <property>
    <name>lens.server.http.notification.read.timeout.millis</name>
    <value>10000</value>
    <description>This is the read timeout for all HTTP Notifications sent by lens server.
      Default read timeout is 10 secs</description>
  </property>

  <property>
    <name>lens.server.grizzly.core.pool.size</name>
    <value>20</value>
    <description>Core pool size for lens grizzly server</description>
  </property>
  <property>
    <name>lens.server.grizzly.max.pool.size</name>
    <value>40</value>
    <description>Max pool size for lens grizzly server</description>
  </property>
   <property>
    <name>lens.server.scheduler.instance.waiting.thread.interval.millis</name>
    <value>300000</value>
    <description>Thread interval for checking the waiting instances in milliseconds</description>
  </property>
  <property>
    <name>lens.server.scheduler.max.job.per.user</name>
    <value>-1</value>
    <description>Maximum number of jobs that can be scheduled by a single user. If the number is less than zero,
       then there is no restriction on the number of jobs scheduled.
    </description>
  </property>
  <property>
    <name>lens.server.query.cost.parser.class</name>
    <value>org.apache.lens.server.api.query.cost.FactPartitionBasedQueryCost$Parser</value>
    <description>The Query cost parser class. Default query cost class used is FactPartitionBasedQueryCost</description>
  </property>

  <property>
    <name>lens.server.query.comparator.classes</name>
    <value>org.apache.lens.server.api.query.comparators.MoreRetriesFirstComparator,org.apache.lens.server.api.query.comparators.QueryPriorityComparator,org.apache.lens.server.api.query.comparators.FIFOQueryComparator</value>
    <description>The Query cost comparator chain. Queries are compared in this order. To compare queries q1 and q2,
    first number of retries are considered. The one with more retries is placed first in the queue. If those are same,
    then their priorities are considered, with higher priorities coming before lower ones. If those are also same,
    then their submission times are considered. The query that was submitted first is placed first.
    </description>
  </property>

  <property>
    <name>lens.cube.metastore.enable.datacompleteness.check</name>
    <value>false</value>
    <description>This property is to enable Data Completeness Checks while resolving partitions.</description>
  </property>
  <property>
    <name>lens.cube.metastore.completeness.checker.class</name>
    <value>org.apache.lens.server.api.metastore.DefaultChecker</value>
    <description>The class that implements the DataCompletenessChecker Interface. This will take effect if the flag
      "lens.cube.metastore.enable.datacompleteness.check" is set.
    </description>
  </property>

  <property>
    <name>lens.server.kdc.login.service.interval.minutes</name>
    <value>360</value>
    <description>interval in minutes to refresh auth token when kerberos is enabled on hdfs and/or hive, metastore</description>
  </property>

  <property>
    <name>lens.server.principal</name>
    <value>lens/_HOST@APACHE.COM</value>
    <description>lens server principal name, must be in format lens/_HOST@KDC_REALM</description>
  </property>

  <property>
    <name>lens.server.ssl.enabled</name>
    <value>false</value>
    <description>flag to enable https communication between lens server and client.</description>
  </property>

  <property>
    <name>lens.server.ssl.file.path</name>
    <value>/tmp/certs</value>
    <description>local path for cert file if ssl ie enabled.</description>
  </property>

  <property>
    <name>lens.server.ssl.password</name>
    <value>password</value>
    <description>password for cert file</description>
  </property>

  <property>
    <name>lens.server.authorizer.class</name>
    <value>org.apache.lens.server.api.authorization.DefaultAuthorizer</value>
    <description>The class that implements the Authorizer Interface. It will be used wherever authorization check
    is enabled</description>
  </property>

</configuration>