mirror of
https://github.com/theupdateframework/python-tuf
synced 2026-05-24 10:08:28 +00:00
122 lines
4.1 KiB
Python
Executable file
122 lines
4.1 KiB
Python
Executable file
#!/usr/bin/env python
|
|
|
|
# Copyright 2012 - 2017, New York University and the TUF contributors
|
|
# SPDX-License-Identifier: MIT OR Apache-2.0
|
|
|
|
"""
|
|
<Program Name>
|
|
mirrors.py
|
|
|
|
<Author>
|
|
Konstantin Andrianov.
|
|
Derived from original mirrors.py written by Geremy Condra.
|
|
|
|
<Started>
|
|
March 12, 2012.
|
|
|
|
<Copyright>
|
|
See LICENSE-MIT OR LICENSE for licensing information.
|
|
|
|
<Purpose>
|
|
Extract a list of mirror urls corresponding to the file type and the location
|
|
of the file with respect to the base url.
|
|
"""
|
|
|
|
import os
|
|
from urllib import parse
|
|
|
|
import securesystemslib # pylint: disable=unused-import
|
|
from securesystemslib import exceptions as sslib_exceptions
|
|
from securesystemslib import formats as sslib_formats
|
|
from securesystemslib.util import file_in_confined_directories
|
|
|
|
from tuf import formats
|
|
|
|
|
|
# The type of file to be downloaded from a repository. The
|
|
# 'get_list_of_mirrors' function supports these file types.
|
|
_SUPPORTED_FILE_TYPES = ['meta', 'target']
|
|
|
|
|
|
def get_list_of_mirrors(file_type, file_path, mirrors_dict):
|
|
"""
|
|
<Purpose>
|
|
Get a list of mirror urls from a mirrors dictionary, provided the type
|
|
and the path of the file with respect to the base url.
|
|
|
|
<Arguments>
|
|
file_type:
|
|
Type of data needed for download, must correspond to one of the strings
|
|
in the list ['meta', 'target']. 'meta' for metadata file type or
|
|
'target' for target file type. It should correspond to
|
|
NAME_SCHEMA format.
|
|
|
|
file_path:
|
|
A relative path to the file that corresponds to RELPATH_SCHEMA format.
|
|
Ex: 'http://url_prefix/targets_path/file_path'
|
|
|
|
mirrors_dict:
|
|
A mirrors_dict object that corresponds to MIRRORDICT_SCHEMA, where
|
|
keys are strings and values are MIRROR_SCHEMA. An example format
|
|
of MIRROR_SCHEMA:
|
|
|
|
{'url_prefix': 'http://localhost:8001',
|
|
'metadata_path': 'metadata/',
|
|
'targets_path': 'targets/',
|
|
'confined_target_dirs': ['targets/snapshot1/', ...],
|
|
'custom': {...}}
|
|
|
|
The 'custom' field is optional.
|
|
|
|
<Exceptions>
|
|
securesystemslib.exceptions.Error, on unsupported 'file_type'.
|
|
|
|
securesystemslib.exceptions.FormatError, on bad argument.
|
|
|
|
<Return>
|
|
List of mirror urls corresponding to the file_type and file_path. If no
|
|
match is found, empty list is returned.
|
|
"""
|
|
|
|
# Checking if all the arguments have appropriate format.
|
|
formats.RELPATH_SCHEMA.check_match(file_path)
|
|
formats.MIRRORDICT_SCHEMA.check_match(mirrors_dict)
|
|
sslib_formats.NAME_SCHEMA.check_match(file_type)
|
|
|
|
# Verify 'file_type' is supported.
|
|
if file_type not in _SUPPORTED_FILE_TYPES:
|
|
raise sslib_exceptions.Error('Invalid file_type argument.'
|
|
' Supported file types: ' + repr(_SUPPORTED_FILE_TYPES))
|
|
path_key = 'metadata_path' if file_type == 'meta' else 'targets_path'
|
|
|
|
list_of_mirrors = []
|
|
for junk, mirror_info in mirrors_dict.items():
|
|
# Does mirror serve this file type at all?
|
|
path = mirror_info.get(path_key)
|
|
if path is None:
|
|
continue
|
|
|
|
# for targets, ensure directory confinement
|
|
if path_key == 'targets_path':
|
|
full_filepath = os.path.join(path, file_path)
|
|
confined_target_dirs = mirror_info.get('confined_target_dirs')
|
|
# confined_target_dirs is optional and can used to confine the client to
|
|
# certain paths on a repository mirror when fetching target files.
|
|
if confined_target_dirs and not file_in_confined_directories(full_filepath,
|
|
confined_target_dirs):
|
|
continue
|
|
|
|
# parse.quote(string) replaces special characters in string using the %xx
|
|
# escape. This is done to avoid parsing issues of the URL on the server
|
|
# side. Do *NOT* pass URLs with Unicode characters without first encoding
|
|
# the URL as UTF-8. We need a long-term solution with #61.
|
|
# http://bugs.python.org/issue1712522
|
|
file_path = parse.quote(file_path)
|
|
url = os.path.join(mirror_info['url_prefix'], path, file_path)
|
|
|
|
# The above os.path.join() result as well as input file_path may be
|
|
# invalid on windows (might contain both separator types), see #1077.
|
|
# Make sure the URL doesn't contain backward slashes on Windows.
|
|
list_of_mirrors.append(url.replace('\\', '/'))
|
|
|
|
return list_of_mirrors
|