Add a snapshot of flutter/engine/src/build to our sdk

build/android/pylib/device/decorators.py

+# Copyright 2014 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.
+
+"""
+Function/method decorators that provide timeout and retry logic.
+"""
+
+import functools
+import os
+import sys
+import threading
+
+from pylib import cmd_helper
+from pylib import constants
+from pylib.device import device_errors
+from pylib.utils import reraiser_thread
+from pylib.utils import timeout_retry
+
+# TODO(jbudorick) Remove once the DeviceUtils implementations are no longer
+#                 backed by AndroidCommands / android_testrunner.
+sys.path.append(os.path.join(constants.DIR_SOURCE_ROOT, 'third_party',
+                             'android_testrunner'))
+import errors as old_errors
+
+DEFAULT_TIMEOUT_ATTR = '_default_timeout'
+DEFAULT_RETRIES_ATTR = '_default_retries'
+
+
+def _TimeoutRetryWrapper(f, timeout_func, retries_func, pass_values=False):
+  """ Wraps a funcion with timeout and retry handling logic.
+
+  Args:
+    f: The function to wrap.
+    timeout_func: A callable that returns the timeout value.
+    retries_func: A callable that returns the retries value.
+    pass_values: If True, passes the values returned by |timeout_func| and
+                 |retries_func| to the wrapped function as 'timeout' and
+                 'retries' kwargs, respectively.
+  Returns:
+    The wrapped function.
+  """
+  @functools.wraps(f)
+  def TimeoutRetryWrapper(*args, **kwargs):
+    timeout = timeout_func(*args, **kwargs)
+    retries = retries_func(*args, **kwargs)
+    if pass_values:
+      kwargs['timeout'] = timeout
+      kwargs['retries'] = retries
+    def impl():
+      return f(*args, **kwargs)
+    try:
+      if isinstance(threading.current_thread(),
+                    timeout_retry.TimeoutRetryThread):
+        return impl()
+      else:
+        return timeout_retry.Run(impl, timeout, retries)
+    except old_errors.WaitForResponseTimedOutError as e:
+      raise device_errors.CommandTimeoutError(str(e)), None, (
+          sys.exc_info()[2])
+    except old_errors.DeviceUnresponsiveError as e:
+      raise device_errors.DeviceUnreachableError(str(e)), None, (
+          sys.exc_info()[2])
+    except reraiser_thread.TimeoutError as e:
+      raise device_errors.CommandTimeoutError(str(e)), None, (
+          sys.exc_info()[2])
+    except cmd_helper.TimeoutError as e:
+      raise device_errors.CommandTimeoutError(str(e)), None, (
+          sys.exc_info()[2])
+  return TimeoutRetryWrapper
+
+
+def WithTimeoutAndRetries(f):
+  """A decorator that handles timeouts and retries.
+
+  'timeout' and 'retries' kwargs must be passed to the function.
+
+  Args:
+    f: The function to decorate.
+  Returns:
+    The decorated function.
+  """
+  get_timeout = lambda *a, **kw: kw['timeout']
+  get_retries = lambda *a, **kw: kw['retries']
+  return _TimeoutRetryWrapper(f, get_timeout, get_retries)
+
+
+def WithExplicitTimeoutAndRetries(timeout, retries):
+  """Returns a decorator that handles timeouts and retries.
+
+  The provided |timeout| and |retries| values are always used.
+
+  Args:
+    timeout: The number of seconds to wait for the decorated function to
+             return. Always used.
+    retries: The number of times the decorated function should be retried on
+             failure. Always used.
+  Returns:
+    The actual decorator.
+  """
+  def decorator(f):
+    get_timeout = lambda *a, **kw: timeout
+    get_retries = lambda *a, **kw: retries
+    return _TimeoutRetryWrapper(f, get_timeout, get_retries)
+  return decorator
+
+
+def WithTimeoutAndRetriesDefaults(default_timeout, default_retries):
+  """Returns a decorator that handles timeouts and retries.
+
+  The provided |default_timeout| and |default_retries| values are used only
+  if timeout and retries values are not provided.
+
+  Args:
+    default_timeout: The number of seconds to wait for the decorated function
+                     to return. Only used if a 'timeout' kwarg is not passed
+                     to the decorated function.
+    default_retries: The number of times the decorated function should be
+                     retried on failure. Only used if a 'retries' kwarg is not
+                     passed to the decorated function.
+  Returns:
+    The actual decorator.
+  """
+  def decorator(f):
+    get_timeout = lambda *a, **kw: kw.get('timeout', default_timeout)
+    get_retries = lambda *a, **kw: kw.get('retries', default_retries)
+    return _TimeoutRetryWrapper(f, get_timeout, get_retries, pass_values=True)
+  return decorator
+
+
+def WithTimeoutAndRetriesFromInstance(
+    default_timeout_name=DEFAULT_TIMEOUT_ATTR,
+    default_retries_name=DEFAULT_RETRIES_ATTR):
+  """Returns a decorator that handles timeouts and retries.
+
+  The provided |default_timeout_name| and |default_retries_name| are used to
+  get the default timeout value and the default retries value from the object
+  instance if timeout and retries values are not provided.
+
+  Note that this should only be used to decorate methods, not functions.
+
+  Args:
+    default_timeout_name: The name of the default timeout attribute of the
+                          instance.
+    default_retries_name: The name of the default retries attribute of the
+                          instance.
+  Returns:
+    The actual decorator.
+  """
+  def decorator(f):
+    def get_timeout(inst, *_args, **kwargs):
+      return kwargs.get('timeout', getattr(inst, default_timeout_name))
+    def get_retries(inst, *_args, **kwargs):
+      return kwargs.get('retries', getattr(inst, default_retries_name))
+    return _TimeoutRetryWrapper(f, get_timeout, get_retries, pass_values=True)
+  return decorator
+