remote_run: use tempfile.gettempdir() for workdirs

scripts/slave/remote_run.py

 #!/usr/bin/env python
 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import argparse
 import copy
 import json
 import logging
 import os
@@ skipping 64 matching lines @@
       help='factory properties in b64 gz JSON format')
   parser.add_argument('--leak', action='store_true',
       help='Refrain from cleaning up generated artifacts.')
   parser.add_argument('--verbose', action='store_true')
 
   group = parser.add_argument_group('LogDog Bootstrap')
   logdog_bootstrap.add_arguments(group)
 
   args = parser.parse_args(argv[1:])
 
-  basedir = os.getcwd()
-  cipd_path = os.path.join(basedir, '.remote_run_cipd')
+  # Keep CIPD directory between builds.
+  cipd_path = os.path.join(os.getcwd(), '.remote_run_cipd')
   _install_cipd_packages(
       cipd_path, cipd.CipdPackage('infra/recipes-py', 'latest'))
 
   with robust_tempdir.RobustTempdir(
       prefix='.remote_run', leak=args.leak) as rt:
+    # Use base directory inside system temporary directory - if we use slave
+    # one (cwd), the paths get too long. Recipes which need different paths
+    # or persistent directories should do so explicitly.
+    basedir = tempfile.gettempdir()
+
     # Explicitly clean up possibly leaked temporary directories
     # from previous runs.
     rt.cleanup(basedir)
 
     tempdir = rt.tempdir(basedir)
     LOGGER.info('Using temporary directory: [%s].', tempdir)
 
     build_data_dir = rt.tempdir(basedir)
     LOGGER.info('Using build data directory: [%s].', build_data_dir)
 
     properties = copy.copy(args.factory_properties)
     properties.update(args.build_properties)
     properties['build_data_dir'] = build_data_dir
     LOGGER.info('Using properties: %r', properties)
     properties_file = os.path.join(tempdir, 'remote_run_properties.json')
     with open(properties_file, 'w') as f:
       json.dump(properties, f)
 
     monitoring_utils.write_build_monitoring_event(build_data_dir, properties)
 
     recipe_cmd = [
         sys.executable,
         os.path.join(cipd_path, 'recipes.py'),
         'remote_run',
         '--repository', args.repository,
         '--revision', args.revision,
         '--workdir', os.path.join(tempdir, 'remote_run_workdir'),
         '--',
         '--properties-file', properties_file,
-        '--workdir', os.path.join(tempdir, 'run_workdir'),
+        '--workdir', os.path.join(tempdir, 'work'),
         args.recipe,
     ]
     recipe_return_code = None
     try:
       cmd = logdog_bootstrap.bootstrap(rt, args, basedir, tempdir, properties,
                                        recipe_cmd)
 
       LOGGER.info('Bootstrapping through LogDog: %s', cmd)
       rc = _call(cmd)
       logdog_bootstrap.assert_not_bootstrap_return_code(rc)
@@ skipping 18 matching lines @@
 
   if update_scripts.update_scripts():
     # Re-execute with the updated remote_run.py.
     return _call([sys.executable] + argv)
 
   return main(argv)
 
 
 if __name__ == '__main__':
   sys.exit(shell_main(sys.argv))