#!/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.
"""Build and upload docker images to Google Container Registry per matrix."""

from __future__ import print_function

import argparse
import atexit
import multiprocessing
import os
import shutil
import subprocess
import sys
import tempfile

# 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

_IMAGE_BUILDER = 'tools/run_tests/dockerize/build_interop_image.sh'
_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())))

# Destination directory inside docker image to keep extra info from build time.
_BUILD_INFO = '/var/local/build_info'

argp = argparse.ArgumentParser(description='Run interop tests.')
argp.add_argument(
    '--gcr_path',
    default='gcr.io/grpc-testing',
    help='Path of docker images in Google Container Registry')

argp.add_argument(
    '--release',
    default='master',
    choices=['all', 'master'] + _RELEASES,
    help='github commit tag to checkout.  When building all '
    'releases defined in client_matrix.py, use "all". Valid only '
    'with --git_checkout.')

argp.add_argument(
    '-l',
    '--language',
    choices=['all'] + sorted(_LANGUAGES),
    nargs='+',
    default=['all'],
    help='Test languages to build docker images for.')

argp.add_argument(
    '--git_checkout',
    action='store_true',
    help='Use a separate git clone tree for building grpc stack. '
    'Required when using --release flag.  By default, current'
    'tree and the sibling will be used for building grpc stack.')

argp.add_argument(
    '--git_checkout_root',
    default='/export/hda3/tmp/grpc_matrix',
    help='Directory under which grpc-go/java/main repo will be '
    'cloned.  Valid only with --git_checkout.')

argp.add_argument(
    '--keep',
    action='store_true',
    help='keep the created local images after uploading to GCR')

argp.add_argument(
    '--reuse_git_root',
    default=False,
    action='store_const',
    const=True,
    help='reuse the repo dir. If False, the existing git root '
    'directory will removed before a clean checkout, because '
    'reusing the repo can cause git checkout error if you switch '
    'between releases.')

argp.add_argument(
    '--upload_images',
    action='store_true',
    help='If set, images will be uploaded to container registry after building.'
)

args = argp.parse_args()


def add_files_to_image(image, with_files, label=None):
    """Add files to a docker image.

  image: docker image name, i.e. grpc_interop_java:26328ad8
  with_files: additional files to include in the docker image.
  label: label string to attach to the image.
  """
    tag_idx = image.find(':')
    if tag_idx == -1:
        jobset.message(
            'FAILED', 'invalid docker image %s' % image, do_newline=True)
        sys.exit(1)
    orig_tag = '%s_' % image
    subprocess.check_output(['docker', 'tag', image, orig_tag])

    lines = ['FROM ' + orig_tag]
    if label:
        lines.append('LABEL %s' % label)

    temp_dir = tempfile.mkdtemp()
    atexit.register(lambda: subprocess.call(['rm', '-rf', temp_dir]))

    # Copy with_files inside the tmp directory, which will be the docker build
    # context.
    for f in with_files:
        shutil.copy(f, temp_dir)
        lines.append('COPY %s %s/' % (os.path.basename(f), _BUILD_INFO))

    # Create a Dockerfile.
    with open(os.path.join(temp_dir, 'Dockerfile'), 'w') as f:
        f.write('\n'.join(lines))

    jobset.message('START', 'Repackaging %s' % image, do_newline=True)
    build_cmd = ['docker', 'build', '--rm', '--tag', image, temp_dir]
    subprocess.check_output(build_cmd)
    dockerjob.remove_image(orig_tag, skip_nonexistent=True)


def build_image_jobspec(runtime, env, gcr_tag, stack_base):
    """Build interop docker image for a language with runtime.

  runtime: a <lang><version> string, for example go1.8.
  env:     dictionary of env to passed to the build script.
  gcr_tag: the tag for the docker image (i.e. v1.3.0).
  stack_base: the local gRPC repo path.
  """
    basename = 'grpc_interop_%s' % runtime
    tag = '%s/%s:%s' % (args.gcr_path, basename, gcr_tag)
    build_env = {'INTEROP_IMAGE': tag, 'BASE_NAME': basename, 'TTY_FLAG': '-t'}
    build_env.update(env)
    image_builder_path = _IMAGE_BUILDER
    if client_matrix.should_build_docker_interop_image_from_release_tag(lang):
        image_builder_path = os.path.join(stack_base, _IMAGE_BUILDER)
    build_job = jobset.JobSpec(
        cmdline=[image_builder_path],
        environ=build_env,
        shortname='build_docker_%s' % runtime,
        timeout_seconds=30 * 60)
    build_job.tag = tag
    return build_job


def build_all_images_for_lang(lang):
    """Build all docker images for a language across releases and runtimes."""
    if not args.git_checkout:
        if args.release != 'master':
            print(
                'Cannot use --release without also enabling --git_checkout.\n')
            sys.exit(1)
        releases = [args.release]
    else:
        if args.release == 'all':
            releases = client_matrix.get_release_tags(lang)
        else:
            # Build a particular release.
            if args.release not in ['master'
                                   ] + client_matrix.get_release_tags(lang):
                jobset.message(
                    'SKIPPED',
                    '%s for %s is not defined' % (args.release, lang),
                    do_newline=True)
                return []
            releases = [args.release]

    images = []
    for release in releases:
        images += build_all_images_for_release(lang, release)
    jobset.message(
        'SUCCESS',
        'All docker images built for %s at %s.' % (lang, releases),
        do_newline=True)
    return images


def build_all_images_for_release(lang, release):
    """Build all docker images for a release across all runtimes."""
    docker_images = []
    build_jobs = []

    env = {}
    # If we not using current tree or the sibling for grpc stack, do checkout.
    stack_base = ''
    if args.git_checkout:
        stack_base = checkout_grpc_stack(lang, release)
        var = {
            'go': 'GRPC_GO_ROOT',
            'java': 'GRPC_JAVA_ROOT',
            'node': 'GRPC_NODE_ROOT'
        }.get(lang, 'GRPC_ROOT')
        env[var] = stack_base

    for runtime in client_matrix.get_runtimes_for_lang_release(lang, release):
        job = build_image_jobspec(runtime, env, release, stack_base)
        docker_images.append(job.tag)
        build_jobs.append(job)

    jobset.message('START', 'Building interop docker images.', do_newline=True)
    print('Jobs to run: \n%s\n' % '\n'.join(str(j) for j in build_jobs))

    num_failures, _ = jobset.run(
        build_jobs,
        newline_on_success=True,
        maxjobs=multiprocessing.cpu_count())
    if num_failures:
        jobset.message(
            'FAILED', 'Failed to build interop docker images.', do_newline=True)
        docker_images_cleanup.extend(docker_images)
        sys.exit(1)

    jobset.message(
        'SUCCESS',
        'All docker images built for %s at %s.' % (lang, release),
        do_newline=True)

    if release != 'master':
        commit_log = os.path.join(stack_base, 'commit_log')
        if os.path.exists(commit_log):
            for image in docker_images:
                add_files_to_image(image, [commit_log], 'release=%s' % release)
    return docker_images


def cleanup():
    if not args.keep:
        for image in docker_images_cleanup:
            dockerjob.remove_image(image, skip_nonexistent=True)


docker_images_cleanup = []
atexit.register(cleanup)


def maybe_apply_patches_on_git_tag(stack_base, lang, release):
    files_to_patch = []

    release_info = client_matrix.LANG_RELEASE_MATRIX[lang].get(release)
    if release_info:
        files_to_patch = release_info.patch
    if not files_to_patch:
        return
    patch_file_relative_path = 'patches/%s_%s/git_repo.patch' % (lang, release)
    patch_file = os.path.abspath(
        os.path.join(os.path.dirname(__file__), patch_file_relative_path))
    if not os.path.exists(patch_file):
        jobset.message('FAILED',
                       'expected patch file |%s| to exist' % patch_file)
        sys.exit(1)
    subprocess.check_output(
        ['git', 'apply', patch_file], cwd=stack_base, stderr=subprocess.STDOUT)

    # TODO(jtattermusch): this really would need simplification and refactoring
    # - "git add" and "git commit" can easily be done in a single command
    # - it looks like the only reason for the existence of the "files_to_patch"
    #   entry is to perform "git add" - which is clumsy and fragile.
    # - we only allow a single patch with name "git_repo.patch". A better design
    #   would be to allow multiple patches that can have more descriptive names.
    for repo_relative_path in files_to_patch:
        subprocess.check_output(
            ['git', 'add', repo_relative_path],
            cwd=stack_base,
            stderr=subprocess.STDOUT)
    subprocess.check_output(
        [
            'git', 'commit', '-m',
            ('Hack performed on top of %s git '
             'tag in order to build and run the %s '
             'interop tests on that tag.' % (lang, release))
        ],
        cwd=stack_base,
        stderr=subprocess.STDOUT)


def checkout_grpc_stack(lang, release):
    """Invokes 'git check' for the lang/release and returns directory created."""
    assert args.git_checkout and args.git_checkout_root

    if not os.path.exists(args.git_checkout_root):
        os.makedirs(args.git_checkout_root)

    repo = client_matrix.get_github_repo(lang)
    # Get the subdir name part of repo
    # For example, 'git@github.com:grpc/grpc-go.git' should use 'grpc-go'.
    repo_dir = os.path.splitext(os.path.basename(repo))[0]
    stack_base = os.path.join(args.git_checkout_root, repo_dir)

    # Clean up leftover repo dir if necessary.
    if not args.reuse_git_root and os.path.exists(stack_base):
        jobset.message('START', 'Removing git checkout root.', do_newline=True)
        shutil.rmtree(stack_base)

    if not os.path.exists(stack_base):
        subprocess.check_call(
            ['git', 'clone', '--recursive', repo],
            cwd=os.path.dirname(stack_base))

    # git checkout.
    jobset.message(
        'START',
        'git checkout %s from %s' % (release, stack_base),
        do_newline=True)
    # We should NEVER do checkout on current tree !!!
    assert not os.path.dirname(__file__).startswith(stack_base)
    output = subprocess.check_output(
        ['git', 'checkout', release], cwd=stack_base, stderr=subprocess.STDOUT)
    maybe_apply_patches_on_git_tag(stack_base, lang, release)
    commit_log = subprocess.check_output(['git', 'log', '-1'], cwd=stack_base)
    jobset.message(
        'SUCCESS',
        'git checkout',
        '%s: %s' % (str(output), commit_log),
        do_newline=True)

    # Write git log to commit_log so it can be packaged with the docker image.
    with open(os.path.join(stack_base, 'commit_log'), 'w') as f:
        f.write(commit_log)
    return stack_base


languages = args.language if args.language != ['all'] else _LANGUAGES
for lang in languages:
    docker_images = build_all_images_for_lang(lang)
    for image in docker_images:
        if args.upload_images:
            jobset.message('START', 'Uploading %s' % image, do_newline=True)
            # docker image name must be in the format <gcr_path>/<image>:<gcr_tag>
            assert image.startswith(args.gcr_path) and image.find(':') != -1
            subprocess.call(['gcloud', 'docker', '--', 'push', image])
        else:
            # Uploading (and overwriting images) by default can easily break things.
            print('Not uploading image %s, run with --upload_images to upload.'
                  % image)