fix(integrations): Fix http putrequest when url is None (#1693)

Modifies behavior of putrequest to check for None on real_url prior to using it.

Fixes GH-1678

Co-authored-by: Matthew Flower <matt.flower@january.com>

sentry_sdk/integrations/stdlib.py

@@ -71,7 +71,7 @@ def putrequest(self, method, url, *args, **kwargs):
         default_port = self.default_port
 
         real_url = url
-        if not real_url.startswith(("http://", "https://")):
+        if real_url is None or not real_url.startswith(("http://", "https://")):
             real_url = "%s://%s%s%s" % (
                 default_port == 443 and "https" or "http",
                 host,

tests/integrations/stdlib/test_httplib.py

@@ -12,10 +12,10 @@
 
 try:
     # py2
-    from httplib import HTTPSConnection
+    from httplib import HTTPConnection, HTTPSConnection
 except ImportError:
     # py3
-    from http.client import HTTPSConnection
+    from http.client import HTTPConnection, HTTPSConnection
 
 try:
     from unittest import mock  # python 3.3 and above
@@ -77,6 +77,16 @@ def before_breadcrumb(crumb, hint):
         assert sys.getrefcount(response) == 2
 
 
+def test_empty_realurl(sentry_init, capture_events):
+    """
+    Ensure that after using sentry_sdk.init you can putrequest a
+    None url.
+    """
+
+    sentry_init(dsn="")
+    HTTPConnection("httpbin.org", port=443).putrequest("POST", None)
+
+
 def test_httplib_misuse(sentry_init, capture_events, request):
     """HTTPConnection.getresponse must be called after every call to
     HTTPConnection.request. However, if somebody does not abide by