text: #!/usr/bin/env python2.7
  
  # Copyright 2015 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.
  
  import argparse
  import glob
  import os
  import shutil
  import sys
  import tempfile
  import multiprocessing
  sys.path.append(os.path.join(os.path.dirname(sys.argv[0]), '..', 'run_tests', 'python_utils'))
  
  assert sys.argv[1:], 'run generate_projects.sh instead of this directly'
  
  import jobset
  
  os.chdir(os.path.join(os.path.dirname(sys.argv[0]), '..', '..'))
  
  argp = argparse.ArgumentParser()
  argp.add_argument('build_files', nargs='+', default=[])
  argp.add_argument('--templates', nargs='+', default=[])
  argp.add_argument('--output_merged', default=None, type=str)
  argp.add_argument('--jobs', '-j', default=multiprocessing.cpu_count(), type=int)
  argp.add_argument('--base', default='.', type=str)
  args = argp.parse_args()
  
  json = args.build_files
  
  test = {} if 'TEST' in os.environ else None
  
  plugins = sorted(glob.glob('tools/buildgen/plugins/*.py'))
  
  templates = args.templates
  if not templates:
    for root, dirs, files in os.walk('templates'):
      for f in files:
        templates.append(os.path.join(root, f))
  
  pre_jobs = []
  base_cmd = ['python2.7', 'tools/buildgen/mako_renderer.py']
  cmd = base_cmd[:]
  for plugin in plugins:
    cmd.append('-p')
    cmd.append(plugin)
  for js in json:
    cmd.append('-d')
    cmd.append(js)
  cmd.append('-w')
  preprocessed_build = '.preprocessed_build'
  cmd.append(preprocessed_build)
  if args.output_merged is not None:
    cmd.append('-M')
    cmd.append(args.output_merged)
  pre_jobs.append(jobset.JobSpec(cmd, shortname='preprocess', timeout_seconds=None))
  
  jobs = []
  for template in reversed(sorted(templates)):
    root, f = os.path.split(template)
    if os.path.splitext(f)[1] == '.template':
      out_dir = args.base + root[len('templates'):]
      out = out_dir + '/' + os.path.splitext(f)[0]
      if not os.path.exists(out_dir):
        os.makedirs(out_dir)
      cmd = base_cmd[:]
      cmd.append('-P')
      cmd.append(preprocessed_build)
      cmd.append('-o')
      if test is None:
        cmd.append(out)
      else:
        tf = tempfile.mkstemp()
        test[out] = tf[1]
        os.close(tf[0])
        cmd.append(test[out])
      cmd.append(args.base + '/' + root + '/' + f)
      jobs.append(jobset.JobSpec(cmd, shortname=out, timeout_seconds=None))
  
  jobset.run(pre_jobs, maxjobs=args.jobs)
  jobset.run(jobs, maxjobs=args.jobs)
  
  if test is not None:
    for s, g in test.iteritems():
      if os.path.isfile(g):
        assert 0 == os.system('diff %s %s' % (s, g)), s
        os.unlink(g)
      else:
        assert 0 == os.system('diff -r %s %s' % (s, g)), s
        shutil.rmtree(g, ignore_errors=True)
  