#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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
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# 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.
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"""Wrapper of Beam runners that's built for running and verifying e2e tests."""

from __future__ import absolute_import
from __future__ import print_function

import logging
import time

from apache_beam.internal import pickler
from apache_beam.options.pipeline_options import GoogleCloudOptions
from apache_beam.options.pipeline_options import StandardOptions
from apache_beam.options.pipeline_options import TestOptions
from apache_beam.runners.dataflow.dataflow_runner import DataflowRunner
from apache_beam.runners.runner import PipelineState

__all__ = ['TestDataflowRunner']

# Dataflow take up to 10mins for the long tail of starting/stopping worker
# pool.
WAIT_IN_STATE_TIMEOUT = 10 * 60


class TestDataflowRunner(DataflowRunner):
  def run_pipeline(self, pipeline, options):
    """Execute test pipeline and verify test matcher"""
    test_options = options.view_as(TestOptions)
    on_success_matcher = test_options.on_success_matcher
    wait_duration = test_options.wait_until_finish_duration
    is_streaming = options.view_as(StandardOptions).streaming

    # [BEAM-1889] Do not send this to remote workers also, there is no need to
    # send this option to remote executors.
    test_options.on_success_matcher = None

    self.result = super(TestDataflowRunner, self).run_pipeline(
        pipeline, options)
    if self.result.has_job:
      # TODO(markflyhigh)(BEAM-1890): Use print since Nose dosen't show logs
      # in some cases.
      print('Found: %s.' % self.build_console_url(options))

    try:
      self.wait_until_in_state(PipelineState.RUNNING)

      if is_streaming and not wait_duration:
        logging.warning('Waiting indefinitely for streaming job.')
      self.result.wait_until_finish(duration=wait_duration)

      if on_success_matcher:
        from hamcrest import assert_that as hc_assert_that
        hc_assert_that(self.result, pickler.loads(on_success_matcher))
    finally:
      if not self.result.is_in_terminal_state():
        self.result.cancel()
        self.wait_until_in_state(PipelineState.CANCELLED)

    return self.result

  def build_console_url(self, options):
    """Build a console url of Dataflow job."""
    project = options.view_as(GoogleCloudOptions).project
    region_id = options.view_as(GoogleCloudOptions).region
    job_id = self.result.job_id()
    return (
        'https://console.cloud.google.com/dataflow/jobsDetail/locations'
        '/%s/jobs/%s?project=%s' % (region_id, job_id, project))

  def wait_until_in_state(self, expected_state, timeout=WAIT_IN_STATE_TIMEOUT):
    """Wait until Dataflow pipeline enters a certain state."""
    if not self.result.has_job:
      raise IOError('Failed to get the Dataflow job id.')

    start_time = time.time()
    while time.time() - start_time <= timeout:
      job_state = self.result.state
      if self.result.is_in_terminal_state() or job_state == expected_state:
        return job_state
      time.sleep(5)

    raise RuntimeError('Timeout after %d seconds while waiting for job %s '
                       'enters expected state %s. Current state is %s.' %
                       (timeout, self.result.job_id(),
                        expected_state, self.result.state))