Auto merge of #22596 - shanavas786:fix-certifi, r=SimonSapin

Fix certifi import error while running ./match bootstrap

Fixes #22590

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- [x] `./mach bootstrap` does not report any errors
- [x] These changes fix #22590

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2 files changed, 20 insertions, 12 deletions

diff --git a/python/servo/devenv_commands.py b/python/servo/devenv_commands.py
index 46862754bd1..b298bf48fd1 100644
--- a/python/servo/devenv_commands.py
+++ b/python/servo/devenv_commands.py
@@ -26,7 +26,7 @@ from mach.decorators import (
 
 from servo.command_base import CommandBase, cd, call, BIN_SUFFIX
 from servo.build_commands import notify_build_done
-from servo.util import STATIC_RUST_LANG_ORG_DIST, URLOPEN_KWARGS
+from servo.util import get_static_rust_lang_org_dist, get_urlopen_kwargs
 
 
 @CommandProvider
@@ -216,8 +216,8 @@ class MachCommands(CommandBase):
              description='Update the Rust version to latest Nightly',
              category='devenv')
     def rustup(self):
-        url = STATIC_RUST_LANG_ORG_DIST + "/channel-rust-nightly-date.txt"
-        nightly_date = urllib2.urlopen(url, **URLOPEN_KWARGS).read()
+        url = get_static_rust_lang_org_dist() + "/channel-rust-nightly-date.txt"
+        nightly_date = urllib2.urlopen(url, **get_urlopen_kwargs()).read()
         toolchain = "nightly-" + nightly_date
         filename = path.join(self.context.topdir, "rust-toolchain")
         with open(filename, "w") as f:
diff --git a/python/servo/util.py b/python/servo/util.py
index 8359ad90b28..818240d39e6 100644
--- a/python/servo/util.py
+++ b/python/servo/util.py
@@ -28,14 +28,22 @@ try:
 except ImportError:
     HAS_SNI = False
 
-# The cafile parameter was added in 2.7.9
-if HAS_SNI and sys.version_info >= (2, 7, 9):
-    import certifi
-    STATIC_RUST_LANG_ORG_DIST = "https://static.rust-lang.org/dist"
-    URLOPEN_KWARGS = {"cafile": certifi.where()}
-else:
-    STATIC_RUST_LANG_ORG_DIST = "https://static-rust-lang-org.s3.amazonaws.com/dist"
-    URLOPEN_KWARGS = {}
+HAS_SNI_AND_RECENT_PYTHON = HAS_SNI and sys.version_info >= (2, 7, 9)
+
+
+def get_static_rust_lang_org_dist():
+    if HAS_SNI_AND_RECENT_PYTHON:
+        return "https://static.rust-lang.org/dist"
+
+    return "https://static-rust-lang-org.s3.amazonaws.com/dist"
+
+
+def get_urlopen_kwargs():
+    # The cafile parameter was added in 2.7.9
+    if HAS_SNI_AND_RECENT_PYTHON:
+        import certifi
+        return {"cafile": certifi.where()}
+    return {}
 
 
 def remove_readonly(func, path, _):
@@ -96,7 +104,7 @@ def download(desc, src, writer, start_byte=0):
         req = urllib2.Request(src)
         if start_byte:
             req = urllib2.Request(src, headers={'Range': 'bytes={}-'.format(start_byte)})
-        resp = urllib2.urlopen(req, **URLOPEN_KWARGS)
+        resp = urllib2.urlopen(req, **get_urlopen_kwargs())
 
         fsize = None
         if resp.info().getheader('Content-Length'):