operations.format.fetch_base: support proxy configuration

Add support for proxy configuration to the fetch_base operation, through
the environment variables ``http_proxy`` and ``https_proxy``. I see no
security concern from passing those variables to the fetcher, as they
are run with the same permissions as the rest of pkgcore, under user
level.

https://github.com/pkgcore/pkgdev/issues/103
Signed-off-by: Arthur Zamarin <arthurzam@gentoo.org>

2 files changed, 10 insertions, 11 deletions

diff --git a/src/pkgcore/fetch/custom.py b/src/pkgcore/fetch/custom.py
index fce7d7c2..d7da08f4 100644
--- a/src/pkgcore/fetch/custom.py
+++ b/src/pkgcore/fetch/custom.py
@@ -37,20 +37,18 @@ class fetcher(base.fetcher):
 
     def __init__(
         self,
-        distdir,
-        command,
+        distdir: str,
+        command: str,
         resume_command=None,
         required_chksums=None,
-        userpriv=True,
-        attempts=10,
-        readonly=False,
-        **extra_env,
+        userpriv: bool = True,
+        attempts: int = 10,
+        readonly: bool = False,
+        **extra_env: str,
     ):
         """
         :param distdir: directory to download files to
-        :type distdir: string
         :param command: shell command to execute to fetch a file
-        :type command: string
         :param resume_command: if not None, command to use for resuming-
             if None, command is reused
         :param required_chksums: if None, all chksums must be verified,
@@ -71,7 +69,7 @@ class fetcher(base.fetcher):
         else:
             self.required_chksums = required_chksums
 
-        def rewrite_command(string):
+        def rewrite_command(string: str):
             new_command = string.replace("\\$", "$")
             new_command = new_command.replace("${DISTDIR}", self.distdir)
             new_command = new_command.replace("$DISTDIR", self.distdir)
@@ -98,10 +96,9 @@ class fetcher(base.fetcher):
         self.readonly = readonly
         self.extra_env = extra_env
 
-    def fetch(self, target):
+    def fetch(self, target: fetchable):
         """Fetch a file.
 
-        :type target: :obj:`pkgcore.fetch.fetchable` instance
         :return: None if fetching failed,
             else on disk location of the copied file
         """
diff --git a/src/pkgcore/operations/format.py b/src/pkgcore/operations/format.py
index 00746c4a..95775f7b 100644
--- a/src/pkgcore/operations/format.py
+++ b/src/pkgcore/operations/format.py
@@ -45,6 +45,8 @@ class fetch_base:
             resumecmd,
             attempts=attempts,
             PATH=os.environ["PATH"],
+            http_proxy=os.environ["http_proxy"],
+            https_proxy=os.environ["https_proxy"],
         )
 
     def fetch_all(self, observer):