green.ssl don't monkey-patch at import time

eventlet#240

eventlet/green/ssl.py

@@ -22,9 +22,13 @@
     has_ciphers = False
     timeout_exc = orig_socket.timeout
 
-__patched__ = ['SSLSocket', 'wrap_socket', 'sslwrap_simple']
+__patched__ = [
+    'SSLSocket', 'wrap_socket', 'sslwrap_simple', 'create_default_context',
+    '_create_default_https_context']
 
 _original_sslsocket = __ssl.SSLSocket
+_original_sslcontext = __ssl.SSLContext
+_original_create_default_context = __ssl.create_default_context
 
 
 class GreenSSLSocket(_original_sslsocket):
@@ -357,11 +361,19 @@ def sslwrap_simple(sock, keyfile=None, certfile=None):
 
 
 if hasattr(__ssl, 'SSLContext'):
-    @functools.wraps(__ssl.SSLContext.wrap_socket)
-    def _green_sslcontext_wrap_socket(self, sock, *a, **kw):
-        return GreenSSLSocket(sock, *a, _context=self, **kw)
-
-    # FIXME:
-    # * GreenSSLContext akin to GreenSSLSocket
-    # * make ssl.create_default_context() use modified SSLContext from globals as usual
-    __ssl.SSLContext.wrap_socket = _green_sslcontext_wrap_socket
+    class GreenSSLContext(_original_sslcontext):
+        __slots__ = ()
+        def wrap_socket(self, sock, *a, **kw):
+            return GreenSSLSocket(sock, *a, _context=self, **kw)
+
+    def green_create_default_context(*a, **kw):
+        # We can't just monkey-patch on the green version of `wrap_socket` on
+        # to SSLContext instances, but SSLContext.create_default_context does a
+        # bunch of work. Rather than re-implementing it all, just switch out
+        # the __class__ to get our `wrap_socket` implementation
+        context = _original_create_default_context(*a, **kw)
+        context.__class__ = GreenSSLContext
+        return context
+
+    create_default_context = green_create_default_context
+    _create_default_https_context = green_create_default_context