annotated_run: extract robust_tempdir so it can be shared with kitchen_run

scripts/slave/robust_tempdir.py

Index: scripts/slave/robust_tempdir.py
diff --git a/scripts/slave/robust_tempdir.py b/scripts/slave/robust_tempdir.py
new file mode 100644
index 0000000000000000000000000000000000000000..2c445ac8b0e8fa1dd7d988264f88372acbced6c3
--- /dev/null
+++ b/scripts/slave/robust_tempdir.py
@@ -0,0 +1,82 @@
+# 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 logging
+import os
+import sys
+import tempfile
+
+# Install Infra build environment.
+BUILD_ROOT = os.path.dirname(os.path.dirname(os.path.dirname(
+                             os.path.abspath(__file__))))
+sys.path.insert(0, os.path.join(BUILD_ROOT, 'scripts'))
+
+from common import chromium_utils
+
+
+LOGGER = logging.getLogger('robust_tempdir')
+
+
+def _ensure_directory(*path):
+  path = os.path.join(*path)
+  if not os.path.isdir(path):
+    os.makedirs(path)
+  return path
+
+
+class RobustTempdir(object):
+  """RobustTempdir is a ContextManager that tracks generated files and cleans
+  them up at exit.
+  """
+
+  def __init__(self, prefix, leak=False):

[kjellander_chromium, 2016/04/13 09:57:44]

Can you document the parameters? It's not obvious what leak actually does.

Maybe even name it something like 'no_cleanup' instead?

+    self._tempdirs = []
+    self._prefix = prefix
+    self._leak = leak
+
+  def cleanup(self, path):
+    self._tempdirs.append(path)
+
+  def tempdir(self, base=None):
+    """Creates a temporary working directory and yields it.
+
+    This creates two levels of directory:
+      <base>/<prefix>
+      <base>/<prefix>/tmpFOO
+
+    On termination, the entire "<base>/<prefix>" directory is deleted,
+    removing the subdirectory created by this instance as well as cleaning up
+    any other temporary subdirectories leaked by previous executions.
+
+    Args:
+      base (str/None): The directory under which the tempdir should be created.
+          If None, the default temporary directory root will be used.
+    """
+    base = base or tempfile.gettempdir()
+    # TODO(phajdan.jr): Clean up leaked directories at the beginning.
+    # Doing so should automatically prevent more out-of-disk-space scenarios.
+    basedir = _ensure_directory(base, self._prefix)
+    self.cleanup(basedir)
+    tdir = tempfile.mkdtemp(dir=basedir)
+    return tdir
+
+  def __enter__(self):
+    return self
+
+  def __exit__(self, _et, _ev, _tb):
+    self.close()
+
+  def close(self):
+    if self._leak:

[kjellander_chromium, 2016/04/13 09:57:44]

This refers to the --leak flag to annotated_run.py, which doesn't really make
sense anymore. I suggest just remove that part.

+      LOGGER.warning('(--leak) Leaking temporary paths: %s', self._tempdirs)
+    else:
+      for path in reversed(self._tempdirs):
+        try:
+          if os.path.isdir(path):
+            LOGGER.debug('Cleaning up temporary directory [%s].', path)
+            chromium_utils.RemoveDirectory(path)
+        except BaseException:
+          LOGGER.exception('Failed to clean up temporary directory [%s].',
+                           path)
+    del(self._tempdirs[:])