sandbox: Add queue_context_manager() method (59b436df) · Commits · BuildStream / buildstream

buildstream/sandbox/sandbox.py

+62 −12

Original line number	Diff line number	Diff line
		@@ -29,7 +29,8 @@ See also: :ref:`sandboxing`.
		"""

		import os
		from collections import namedtuple
		from collections import deque, namedtuple
		from contextlib import contextmanager

		from .._exceptions import ImplError, BstError
		from ..storage._filebaseddirectory import FileBasedDirectory
		@@ -73,6 +74,22 @@ class SandboxFlags():
		"""


		# _QueueEntryType()
		#
		# A type for sandbox queue entries.
		#
		class _QueueEntryType():

		# A queued command.
		COMMAND = 1

		# A queued context manager enter.
		CONTEXT_MANAGER_ENTER = 2

		# A queued context manager exit.
		CONTEXT_MANAGER_EXIT = 3


		class Sandbox():
		"""Sandbox()

		@@ -265,7 +282,8 @@ class Sandbox():

		Since: 1.4
		"""
		entry = namedtuple('QueueEntry', ['command', 'cwd', 'env', 'start_callback', 'complete_callback'])
		entry = namedtuple('QueueEntry', ['type', 'command', 'cwd', 'env', 'start_callback', 'complete_callback'])
		entry.type = _QueueEntryType.COMMAND
		entry.command = command
		entry.cwd = self._get_work_directory(cwd=cwd)
		entry.env = self._get_environment(cwd=cwd, env=env)
		@@ -273,6 +291,24 @@ class Sandbox():
		entry.complete_callback = complete_callback
		self._queue.append(entry)

		@contextmanager
		def queue_context_manager(self, cm):
		"""Queue entering and exiting a context manager

		Args:
		cm: A context manager

		Since: 1.4
		"""
		entry = namedtuple('QueueEntry', ['type', 'cm'])
		entry.type = _QueueEntryType.CONTEXT_MANAGER_ENTER
		entry.cm = cm
		self._queue.append(entry)
		yield
		entry = namedtuple('QueueEntry', ['type'])
		entry.type = _QueueEntryType.CONTEXT_MANAGER_EXIT
		self._queue.append(entry)

		def run_queue(self, flags):
		"""Run a command in the sandbox.

		@@ -289,7 +325,11 @@ class Sandbox():
		queue = self._queue
		self._queue = []

		# Stack of pending context manager exit methods
		exit_stack = deque()
		try:
		for entry in queue:
		if entry.type == _QueueEntryType.COMMAND:
		if entry.start_callback:
		entry.start_callback()
		if entry.command:
		@@ -299,6 +339,16 @@ class Sandbox():
		entry.complete_callback(exit_code)
		if exit_code != 0:
		break
		elif entry.type == _QueueEntryType.CONTEXT_MANAGER_ENTER:
		entry.cm.__enter__()
		exit_stack.append(entry.cm.__exit__)
		elif entry.type == _QueueEntryType.CONTEXT_MANAGER_EXIT:
		exit_cb = exit_stack.pop()
		exit_cb(None, None, None)
		finally:
		while exit_stack:
		exit_cb = exit_stack.pop()
		exit_cb(None, None, None)

		################################################
		# Private methods #