feedleware/TwitchRSS/vendor.py

72 lines
2.7 KiB
Python

#
# Copyright 2014 Jon Wayne Parrott, [proppy], Michael R. Bernstein
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# Notes:
# - Imported from https://github.com/jonparrott/Darth-Vendor/.
# - Added license header.
# - Renamed `darth.vendor` to `vendor.add` to match upcoming SDK interface.
# - Renamed `position` param to `index` to match upcoming SDK interface.
# - Removed funny arworks docstring.
import site
import os.path
import sys
def add(folder, index=1):
"""
Adds the given folder to the python path. Supports namespaced packages.
By default, packages in the given folder take precedence over site-packages
and any previous path manipulations.
Args:
folder: Path to the folder containing packages, relative to ``os.getcwd()``
position: Where in ``sys.path`` to insert the vendor packages. By default
this is set to 1. It is inadvisable to set it to 0 as it will override
any modules in the current working directory.
"""
# Check if the path contains a virtualenv.
site_dir = os.path.join(folder, 'lib', 'python' + sys.version[:3], 'site-packages')
if os.path.exists(site_dir):
folder = site_dir
# Otherwise it's just a normal path, make it absolute.
else:
folder = os.path.join(os.path.dirname(__file__), folder)
# Use site.addsitedir() because it appropriately reads .pth
# files for namespaced packages. Unfortunately, there's not an
# option to choose where addsitedir() puts its paths in sys.path
# so we have to do a little bit of magic to make it play along.
# We're going to grab the current sys.path and split it up into
# the first entry and then the rest. Essentially turning
# ['.', '/site-packages/x', 'site-packages/y']
# into
# ['.'] and ['/site-packages/x', 'site-packages/y']
# The reason for this is we want '.' to remain at the top of the
# list but we want our vendor files to override everything else.
sys.path, remainder = sys.path[:1], sys.path[1:]
# Now we call addsitedir which will append our vendor directories
# to sys.path (which was truncated by the last step.)
site.addsitedir(folder)
# Finally, we'll add the paths we removed back.
# The final product is something like this:
# ['.', '/vendor-folder', /site-packages/x', 'site-packages/y']
sys.path.extend(remainder)