This module provides a pool manager that uses Google App Engine's
`URLFetch Service <https://cloud.google.com/appengine/docs/python/urlfetch>`_.
Example usage::
from urllib3 import PoolManager
from urllib3.contrib.appengine import AppEngineManager, is_appengine_sandbox
if is_appengine_sandbox():
# AppEngineManager uses AppEngine's URLFetch API behind the scenes
http = AppEngineManager()
else:
# PoolManager uses a socket-level API behind the scenes
http = PoolManager()
r = http.request('GET', 'https://google.com/')
There are `limitations <https://cloud.google.com/appengine/docs/python/\
urlfetch/#Python_Quotas_and_limits>`_ to the URLFetch service and it may not be
the best choice for your application. There are three options for using
urllib3 on Google App Engine:
1. You can use :class:`AppEngineManager` with URLFetch. URLFetch is
cost-effective in many circumstances as long as your usage is within the
limitations.
2. You can use a normal :class:`~urllib3.PoolManager` by enabling sockets.
Sockets also have `limitations and restrictions
<https://cloud.google.com/appengine/docs/python/sockets/\
#limitations-and-restrictions>`_ and have a lower free quota than URLFetch.
To use sockets, be sure to specify the following in your ``app.yaml``::
env_variables:
GAE_USE_SOCKETS_HTTPLIB : 'true'
3. If you are using `App Engine Flexible
<https://cloud.google.com/appengine/docs/flexible/>`_, you can use the standard
:class:`PoolManager` without any configuration or special environment variables.