#!/usr/bin/env python2.7
# Copyright 2017 gRPC authors.
#
# 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.
"""Run tests using docker images in Google Container Registry per matrix."""

from __future__ import print_function

import argparse
import atexit
import json
import multiprocessing
import os
import re
import subprocess
import sys
import uuid

# Language Runtime Matrix
import client_matrix

python_util_dir = os.path.abspath(
    os.path.join(os.path.dirname(__file__), '../run_tests/python_utils'))
sys.path.append(python_util_dir)
import dockerjob
import jobset
import report_utils
import upload_test_results

_TEST_TIMEOUT_SECONDS = 60
_PULL_IMAGE_TIMEOUT_SECONDS = 15 * 60
_MAX_PARALLEL_DOWNLOADS = 6
_LANGUAGES = client_matrix.LANG_RUNTIME_MATRIX.keys()
# All gRPC release tags, flattened, deduped and sorted.
_RELEASES = sorted(
    list(
        set(release
            for release_dict in client_matrix.LANG_RELEASE_MATRIX.values()
            for release in release_dict.keys())))

argp = argparse.ArgumentParser(description='Run interop tests.')
argp.add_argument('-j', '--jobs', default=multiprocessing.cpu_count(), type=int)
argp.add_argument('--gcr_path',
                  default='gcr.io/grpc-testing',
                  help='Path of docker images in Google Container Registry')
argp.add_argument('--release',
                  default='all',
                  choices=['all'] + _RELEASES,
                  help='Release tags to test.  When testing all '
                  'releases defined in client_matrix.py, use "all".')
argp.add_argument('-l',
                  '--language',
                  choices=['all'] + sorted(_LANGUAGES),
                  nargs='+',
                  default=['all'],
                  help='Languages to test')
argp.add_argument(
    '--keep',
    action='store_true',
    help='keep the created local images after finishing the tests.')
argp.add_argument('--report_file',
                  default='report.xml',
                  help='The result file to create.')
argp.add_argument('--allow_flakes',
                  default=False,
                  action='store_const',
                  const=True,
                  help=('Allow flaky tests to show as passing (re-runs failed '
                        'tests up to five times)'))
argp.add_argument('--bq_result_table',
                  default='',
                  type=str,
                  nargs='?',
                  help='Upload test results to a specified BQ table.')
# Requests will be routed through specified VIP by default.
# See go/grpc-interop-tests (internal-only) for details.
argp.add_argument('--server_host',
                  default='74.125.206.210',
                  type=str,
                  nargs='?',
                  help='The gateway to backend services.')


def _get_test_images_for_lang(lang, release_arg, image_path_prefix):
    """Find docker images for a language across releases and runtimes.

  Returns dictionary of list of (<tag>, <image-full-path>) keyed by runtime.
  """
    if release_arg == 'all':
        # Use all defined releases for given language
        releases = client_matrix.get_release_tags(lang)
    else:
        # Look for a particular release.
        if release_arg not in client_matrix.get_release_tags(lang):
            jobset.message('SKIPPED',
                           'release %s for %s is not defined' %
                           (release_arg, lang),
                           do_newline=True)
            return {}
        releases = [release_arg]

    # Image tuples keyed by runtime.
    images = {}
    for tag in releases:
        for runtime in client_matrix.get_runtimes_for_lang_release(lang, tag):
            image_name = '%s/grpc_interop_%s:%s' % (image_path_prefix, runtime,
                                                    tag)
            image_tuple = (tag, image_name)

            if not images.has_key(runtime):
                images[runtime] = []
            images[runtime].append(image_tuple)
    return images


def _read_test_cases_file(lang, runtime, release):
    """Read test cases from a bash-like file and return a list of commands"""
    # Check to see if we need to use a particular version of test cases.
    release_info = client_matrix.LANG_RELEASE_MATRIX[lang].get(release)
    if release_info:
        testcases_file = release_info.testcases_file
    if not testcases_file:
        # TODO(jtattermusch): remove the double-underscore, it is pointless
        testcases_file = '%s__master' % lang

    # For csharp, the testcases file used depends on the runtime
    # TODO(jtattermusch): remove this odd specialcase
    if lang == 'csharp' and runtime == 'csharpcoreclr':
        testcases_file = testcases_file.replace('csharp_', 'csharpcoreclr_')

    testcases_filepath = os.path.join(os.path.dirname(__file__), 'testcases',
                                      testcases_file)
    lines = []
    with open(testcases_filepath) as f:
        for line in f.readlines():
            line = re.sub('\\#.*$', '', line)  # remove hash comments
            line = line.strip()
            if line and not line.startswith('echo'):
                # Each non-empty line is a treated as a test case command
                lines.append(line)
    return lines


def _cleanup_docker_image(image):
    jobset.message('START', 'Cleanup docker image %s' % image, do_newline=True)
    dockerjob.remove_image(image, skip_nonexistent=True)


args = argp.parse_args()


# caches test cases (list of JobSpec) loaded from file.  Keyed by lang and runtime.
def _generate_test_case_jobspecs(lang, runtime, release, suite_name):
    """Returns the list of test cases from testcase files per lang/release."""
    testcase_lines = _read_test_cases_file(lang, runtime, release)

    job_spec_list = []
    for line in testcase_lines:
        # TODO(jtattermusch): revisit the logic for updating test case commands
        # what it currently being done seems fragile.

        # Extract test case name from the command line
        m = re.search(r'--test_case=(\w+)', line)
        testcase_name = m.group(1) if m else 'unknown_test'

        # Extract the server name from the command line
        if '--server_host_override=' in line:
            m = re.search(
                r'--server_host_override=((.*).sandbox.googleapis.com)', line)
        else:
            m = re.search(r'--server_host=((.*).sandbox.googleapis.com)', line)
        server = m.group(1) if m else 'unknown_server'
        server_short = m.group(2) if m else 'unknown_server'

        # replace original server_host argument
        assert '--server_host=' in line
        line = re.sub(r'--server_host=[^ ]*',
                      r'--server_host=%s' % args.server_host, line)

        # some interop tests don't set server_host_override (see #17407),
        # but we need to use it if different host is set via cmdline args.
        if args.server_host != server and not '--server_host_override=' in line:
            line = re.sub(r'(--server_host=[^ ]*)',
                          r'\1 --server_host_override=%s' % server, line)

        spec = jobset.JobSpec(cmdline=line,
                              shortname='%s:%s:%s:%s' %
                              (suite_name, lang, server_short, testcase_name),
                              timeout_seconds=_TEST_TIMEOUT_SECONDS,
                              shell=True,
                              flake_retries=5 if args.allow_flakes else 0)
        job_spec_list.append(spec)
    return job_spec_list


def _pull_image_for_lang(lang, image, release):
    """Pull an image for a given language form the image registry."""
    cmdline = [
        'time gcloud docker -- pull %s && time docker run --rm=true %s /bin/true'
        % (image, image)
    ]
    return jobset.JobSpec(cmdline=cmdline,
                          shortname='pull_image_{}'.format(image),
                          timeout_seconds=_PULL_IMAGE_TIMEOUT_SECONDS,
                          shell=True,
                          flake_retries=2)


def _test_release(lang, runtime, release, image, xml_report_tree, skip_tests):
    total_num_failures = 0
    suite_name = '%s__%s_%s' % (lang, runtime, release)
    job_spec_list = _generate_test_case_jobspecs(lang, runtime, release,
                                                 suite_name)

    if not job_spec_list:
        jobset.message('FAILED', 'No test cases were found.', do_newline=True)
        total_num_failures += 1
    else:
        num_failures, resultset = jobset.run(job_spec_list,
                                             newline_on_success=True,
                                             add_env={'docker_image': image},
                                             maxjobs=args.jobs,
                                             skip_jobs=skip_tests)
        if args.bq_result_table and resultset:
            upload_test_results.upload_interop_results_to_bq(
                resultset, args.bq_result_table)
        if skip_tests:
            jobset.message('FAILED', 'Tests were skipped', do_newline=True)
            total_num_failures += 1
        if num_failures:
            total_num_failures += num_failures

        report_utils.append_junit_xml_results(xml_report_tree, resultset,
                                              'grpc_interop_matrix', suite_name,
                                              str(uuid.uuid4()))
    return total_num_failures


def _run_tests_for_lang(lang, runtime, images, xml_report_tree):
    """Find and run all test cases for a language.

  images is a list of (<release-tag>, <image-full-path>) tuple.
  """
    skip_tests = False
    total_num_failures = 0

    max_pull_jobs = min(args.jobs, _MAX_PARALLEL_DOWNLOADS)
    max_chunk_size = max_pull_jobs
    chunk_count = (len(images) + max_chunk_size) // max_chunk_size

    for chunk_index in range(chunk_count):
        chunk_start = chunk_index * max_chunk_size
        chunk_size = min(max_chunk_size, len(images) - chunk_start)
        chunk_end = chunk_start + chunk_size
        pull_specs = []
        if not skip_tests:
            for release, image in images[chunk_start:chunk_end]:
                pull_specs.append(_pull_image_for_lang(lang, image, release))

        # NOTE(rbellevi): We batch docker pull operations to maximize
        # parallelism, without letting the disk usage grow unbounded.
        pull_failures, _ = jobset.run(pull_specs,
                                      newline_on_success=True,
                                      maxjobs=max_pull_jobs)
        if pull_failures:
            jobset.message(
                'FAILED',
                'Image download failed. Skipping tests for language "%s"' %
                lang,
                do_newline=True)
            skip_tests = True
        for release, image in images[chunk_start:chunk_end]:
            total_num_failures += _test_release(lang, runtime, release, image,
                                                xml_report_tree, skip_tests)
        if not args.keep:
            for _, image in images[chunk_start:chunk_end]:
                _cleanup_docker_image(image)
    if not total_num_failures:
        jobset.message('SUCCESS',
                       'All {} tests passed'.format(lang),
                       do_newline=True)
    else:
        jobset.message('FAILED',
                       'Some {} tests failed'.format(lang),
                       do_newline=True)

    return total_num_failures


languages = args.language if args.language != ['all'] else _LANGUAGES
total_num_failures = 0
_xml_report_tree = report_utils.new_junit_xml_tree()
for lang in languages:
    docker_images = _get_test_images_for_lang(lang, args.release, args.gcr_path)
    for runtime in sorted(docker_images.keys()):
        total_num_failures += _run_tests_for_lang(lang, runtime,
                                                  docker_images[runtime],
                                                  _xml_report_tree)

report_utils.create_xml_report_file(_xml_report_tree, args.report_file)

if total_num_failures:
    sys.exit(1)
sys.exit(0)
