Trac #33771: SSLContext needs an argument

with python 3.10, one sees a deprecation
{{{
sage: oeis([5,21,84,330])
.../sage/local/var/lib/sage/venv-python3.10/lib/python3.10/site-
packages/sage/databases/oeis.py:203: DeprecationWarning:
ssl.SSLContext() without protocol argument is deprecated.
  f = urlopen(url, context=SSLContext())
.../sage/local/var/lib/sage/venv-python3.10/lib/python3.10/site-
packages/sage/databases/oeis.py:203: DeprecationWarning:
ssl.PROTOCOL_TLS is deprecated
  f = urlopen(url, context=SSLContext())
0: A002054: Binomial coefficient C(2n+1, n-1).
1: A289797: p-INVERT of the triangular numbers (A000217), where p(S) = 1
- S - S^2.
2: A284911: Number of partitions of n^2 that are the sum of n not
necessarily distinct partitions of n into distinct parts.
}}}

URL: https://trac.sagemath.org/33771
Reported by: chapoton
Ticket author(s): Frédéric Chapoton
Reviewer(s): Thierry Monteil

Author: Release Manager

src/sage/arith/misc.py

@@ -2033,7 +2033,7 @@ def xkcd(n=""):
     import contextlib
     import json
     from sage.misc.html import html
-    from ssl import SSLContext
+    from ssl import create_default_context as default_context
 
     from urllib.request import urlopen
     from urllib.error import HTTPError, URLError
@@ -2046,7 +2046,7 @@ def xkcd(n=""):
         url = "https://xkcd.com/{}/info.0.json".format(n)
 
     try:
-        with contextlib.closing(urlopen(url, context=SSLContext())) as f:
+        with contextlib.closing(urlopen(url, context=default_context())) as f:
             data = f.read()
     except HTTPError as error:
         if error.getcode() == 400:  # this error occurs when asking for a non valid comic number

src/sage/combinat/designs/covering_design.py

@@ -46,7 +46,7 @@
 # ****************************************************************************
 
 from urllib.request import urlopen
-from ssl import SSLContext
+from ssl import create_default_context as default_context
 
 from sage.misc.sage_eval import sage_eval
 from sage.structure.sage_object import SageObject
@@ -529,7 +529,7 @@ def best_known_covering_design_www(v, k, t, verbose=False):
     if verbose:
         print("Looking up the bounds at %s" % url)
 
-    f = urlopen(url, context=SSLContext())
+    f = urlopen(url, context=default_context())
     try:
         s = bytes_to_str(f.read())
     finally:

src/sage/databases/oeis.py

@@ -160,7 +160,7 @@
 # ****************************************************************************
 from urllib.request import urlopen
 from urllib.parse import urlencode
-from ssl import SSLContext
+from ssl import create_default_context as default_context
 
 from sage.structure.sage_object import SageObject
 from sage.structure.unique_representation import UniqueRepresentation
@@ -200,7 +200,7 @@ def _fetch(url):
     """
     try:
         verbose("Fetching URL %s ..." % url, caller_name='OEIS')
-        f = urlopen(url, context=SSLContext())
+        f = urlopen(url, context=default_context())
         result = f.read()
         f.close()
         return bytes_to_str(result)

src/sage/databases/sloane.py

@@ -202,7 +202,7 @@ def install(self, oeis_url="https://oeis.org/stripped.gz",
             raise IOError("Sloane encyclopedia is already installed")
 
         tm = verbose("Downloading stripped version of Sloane encyclopedia")
-        ssl._create_default_https_context = ssl.SSLContext
+        ssl._create_default_https_context = ssl.create_default_context
         try:
             fname, _ = urlretrieve(oeis_url)
         except IOError as msg:

src/sage/features/internet.py

@@ -40,11 +40,11 @@ def _is_present(self):
         """
         import urllib.error
         from urllib.request import Request, urlopen
-        from ssl import SSLContext
+        from ssl import create_default_context as default_context
 
         req = Request("https://www.sagemath.org", headers={"User-Agent": "sage-doctest"})
         try:
-            urlopen(req, timeout=1, context=SSLContext())
+            urlopen(req, timeout=1, context=default_context())
             return FeatureTestResult(self, True)
         except urllib.error.URLError:
             return FeatureTestResult(self, False)

src/sage/graphs/isgci.py

@@ -400,8 +400,7 @@ class is defined by the exclusion of subgraphs, one can write a generic
 import os
 import zipfile
 from urllib.request import urlopen
-from ssl import SSLContext
-
+from ssl import create_default_context as default_context
 
 #*****************************************************************************
 #      Copyright (C) 2011 Nathann Cohen <[email protected]>
@@ -828,7 +827,8 @@ def _download_db(self):
             sage: graph_classes._download_db() # Not tested -- requires internet
         """
         from sage.misc.misc import SAGE_TMP
-        u = urlopen('https://www.graphclasses.org/data.zip', context=SSLContext())
+        u = urlopen('https://www.graphclasses.org/data.zip',
+                    context=default_context())
         localFile = open(os.path.join(SAGE_TMP, 'isgci.zip'), 'w')
         localFile.write(u.read())
         localFile.close()

src/sage/interfaces/mathematica.py

@@ -1140,11 +1140,12 @@ def request_wolfram_alpha(input, verbose=False):
     from urllib.request import Request, build_opener, HTTPCookieProcessor, HTTPSHandler
     import json
     from http.cookiejar import CookieJar
-    from ssl import SSLContext
+    from ssl import create_default_context as default_context
 
     # we need cookies for this...
     cj = CookieJar()
-    opener = build_opener(HTTPCookieProcessor(cj), HTTPSHandler(context=SSLContext()))
+    opener = build_opener(HTTPCookieProcessor(cj),
+                          HTTPSHandler(context=default_context()))
     # build initial query for code
     req = Request("https://www.wolframalpha.com/input/api/v1/code")
     resp = opener.open(req)

src/sage/misc/messaging.py

@@ -14,7 +14,7 @@
 
 import http.client as httplib
 from urllib.parse import urlencode
-from ssl import SSLContext
+from ssl import create_default_context as default_context
 
 pushover_defaults = {"token": "Eql67F14ohOZJ0AtEBJJU7FiLAk8wK"}
 
@@ -77,7 +77,8 @@ def pushover(message, **kwds):
     request.update(pushover_defaults)
     request.update(kwds)
 
-    conn = httplib.HTTPSConnection("api.pushover.net:443", context=SSLContext())
+    conn = httplib.HTTPSConnection("api.pushover.net:443",
+                                   context=default_context())
     conn.request("POST", "/1/messages.json",
                  urlencode(request),
                  {"Content-type": "application/x-www-form-urlencoded"})

src/sage/misc/package.py

@@ -51,7 +51,7 @@
 from pathlib import Path
 from urllib.request import urlopen
 from urllib.error import URLError
-from ssl import SSLContext
+from ssl import create_default_context as default_context
 
 DEFAULT_PYPI = 'https://pypi.org/pypi'
 
@@ -110,7 +110,7 @@ def pip_remote_version(pkg, pypi_url=DEFAULT_PYPI, ignore_URLError=False):
     url = '{pypi_url}/{pkg}/json'.format(pypi_url=pypi_url, pkg=pkg)
 
     try:
-        f = urlopen(url, context=SSLContext())
+        f = urlopen(url, context=default_context())
         text = f.read()
         f.close()
     except URLError:

src/sage/misc/remote_file.py

@@ -3,7 +3,7 @@
 
 import os
 from urllib.request import Request, urlopen
-from ssl import SSLContext
+from ssl import create_default_context as default_context
 
 
 def get_remote_file(filename, verbose=True):
@@ -43,7 +43,7 @@ def get_remote_file(filename, verbose=True):
     if verbose:
         print("Loading started")
 
-    content = urlopen(req, timeout=1, context=SSLContext())
+    content = urlopen(req, timeout=1, context=default_context())
     with open(temp_name, 'wb') as f:
         f.write(content.read())