impala/tests/performance/query_executor.py

# Copyright (c) 2012 Cloudera, Inc. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# Module used for executing queries and gathering results.
# The QueryExecutor is meant to be generic and doesn't
# have the knowledge of how to actually execute a query. It takes a query and its config
# and executes is against a executor function.
# For example (in pseudo-code):
#
# def exec_func(query, config):
# ...
#
# config = ImpalaBeeswaxQueryExecConfig()
# executor = QueryExecutor('beeswax', query, config, exec_func)
# executor.run()
# result = executor.result

import logging
import os

from tests.beeswax.impala_beeswax import ImpalaBeeswaxClient, ImpalaBeeswaxResult
from tests.performance.query import Query, QueryResult

# Setup logging for this module.
logging.basicConfig(level=logging.INFO, format='[%(name)s] %(threadName)s: %(message)s')
LOG = logging.getLogger('query_executor')
LOG.setLevel(level=logging.INFO)

# globals.
hive_result_regex = 'Time taken: (\d*).(\d*) seconds'

## TODO: Split executors into their own modules.
class QueryExecConfig(object):
  """Base Class for Execution Configs

  Attributes:
    plugin_runner (PluginRunner?)
  """
  def __init__(self, plugin_runner=None):
    self.plugin_runner = plugin_runner


class ImpalaQueryExecConfig(QueryExecConfig):
  """Base class for Impala query execution config

  Attributes:
    impalad (str): address of impalad <host>:<port>
  """

  def __init__(self, plugin_runner=None, impalad='localhost:21000'):
    super(ImpalaQueryExecConfig, self).__init__(plugin_runner=plugin_runner)
    self._impalad = impalad

  @property
  def impalad(self):
    return self._impalad

  @impalad.setter
  def impalad(self, value):
    self._impalad = value


class JdbcQueryExecConfig(ImpalaQueryExecConfig):
  """Impala query execution config for jdbc

  Attributes:
    tranport (?): ?
  """

  JDBC_CLIENT_PATH = os.path.join(os.environ['IMPALA_HOME'], 'bin/run-jdbc-client.sh')

  def __init__(self, plugin_runner=None, impalad='localhost:21050', transport=None):
    super(JdbcQueryExecConfig, self).__init__(plugin_runner=plugin_runner,
        impalad=impalad)
    self.transport = transport

  @property
  def jdbc_client_cmd(self):
    """The args to run the jdbc client.

    Constructed on the fly, since the impalad it points to can change.
    """
    return JdbcQueryExecConfig.JDBC_CLIENT_PATH + ' -i "%s" -t %s' % (self._impalad,
                                                                      self.transport)

class BeeswaxQueryExecConfig(ImpalaQueryExecConfig):
  """Impala query execution config for beeswax

  Args:
    use_kerberos (boolean)
    exec_options (str): String formatted as "opt1:val1;opt2:val2"
    impalad (str): address of impalad <host>:<port>
    plugin_runner (?): ?

  Attributes:
    use_kerberos (boolean)
    exec_options (dict str -> str): execution options
  """

  def __init__(self, use_kerberos=False, exec_options=None, impalad='localhost:21000',
      plugin_runner=None):
    super(BeeswaxQueryExecConfig, self).__init__(plugin_runner=plugin_runner,
        impalad=impalad)
    self.use_kerberos = use_kerberos
    self.exec_options = dict()
    self._build_options(exec_options)

  def _build_options(self, exec_options):
    """Read the exec_options into self.exec_options

    Args:
      exec_options (str): String formatted as "opt1:val1;opt2:val2"
    """

    if exec_options:
      # exec_options are seperated by ; on the command line
      options = exec_options.split(';')
      for option in options:
        key, value = option.split(':')
        # The keys in ImpalaService QueryOptions are upper case.
        self.exec_options[key.upper()] = value


class QueryExecutor(object):
  """Executes a query.

  Args:
    name (str): eg. "hive"
    query (str): string containing SQL query to be executed
    func (function): Function that accepts a QueryExecOption parameter and returns a
      QueryResult. Eg. execute_using_impala_beeswax
    config (QueryExecOption)
    exit_on_error (boolean): Exit right after an error encountered.

  Attributes:
    exec_func (function): Function that accepts a QueryExecOption parameter and returns a
      QueryResult.
    exec_config (QueryExecOption)
    query (str): string containing SQL query to be executed
    exit_on_error (boolean): Exit right after an error encountered.
    executor_name (str): eg. "hive"
    result (QueryResult): Contains the result after execute method is called.
  """

  def __init__(self, name, query, func, config, exit_on_error):
    self.exec_func = func
    self.exec_config = config
    self.query = query
    self.exit_on_error = exit_on_error
    self.executor_name = name
    self._result = QueryResult(query, query_config=self.exec_config)

  def prepare(self, impalad):
    """Prepare the query to be run.

    For now, this sets the impalad that the query connects to. If the executor is hive,
    it's a no op.
    """
    if self.executor_name != 'hive':
      self.exec_config.impalad = impalad

  def execute(self):
    """Execute the query using the given execution function"""
    self._result = self.exec_func(self.query, self.exec_config)
    if not self._result.success:
      if self.exit_on_error:
        raise RuntimeError(self._result.query_error)
      else:
        LOG.info("Continuing execution")

  @property
  def result(self):
    """Getter for the result of the query execution.

    A result is a QueryResult object that contains the details of a single run of the
    query.
    """
    return self._result