Use attributes instead of custom_sampling_context in WSGI

Author: sentrivana

MIGRATION_GUIDE.md

@@ -20,6 +20,7 @@ Looking to upgrade from Sentry SDK 2.x to 3.x? Here's a comprehensive list of wh
 - clickhouse-driver integration: The query is now available under the `db.query.text` span attribute (only if `send_default_pii` is `True`).
 - `sentry_sdk.init` now returns `None` instead of a context manager.
 - The `sampling_context` argument of `traces_sampler` now additionally contains all span attributes known at span start.
+- The `sampling_context` argument of `traces_sampler` doesn't contain the `wsgi_environ` object anymore. Instead, the individual properties are accessible as `wsgi_environ.PATH_INFO`... If you need more data accessible in the `traces_sampler`, provide additional `attributes` to your `start_span`. # TODO
 
 ### Removed
 

sentry_sdk/integrations/wsgi.py

@@ -120,7 +120,7 @@ def __call__(self, environ, start_response):
                                 name=DEFAULT_TRANSACTION_NAME,
                                 source=TRANSACTION_SOURCE_ROUTE,
                                 origin=self.span_origin,
-                                custom_sampling_context={"wsgi_environ": environ},
+                                attributes=_prepopulate_attributes(environ),
                             )
                             if should_trace
                             else nullcontext()
@@ -309,3 +309,28 @@ def event_processor(event, hint):
         return event
 
     return event_processor
+
+
+def _prepopulate_attributes(wsgi_environ):
+    attributes = {}
+
+    for attr in (
+        "CONTENT_LENGTH",
+        "CONTENT_TYPE",
+        "PATH_INFO",
+        "QUERY_STRING",
+        "REQUEST_METHOD",
+        "SCRIPT_NAME",
+        "SERVER_NAME",
+        "SERVER_PORT",
+        "SERVER_PROTOCOL",
+        "multithread",
+        "multiprocess",
+        "run_once",
+        "url_scheme",
+        "version",
+    ):
+        if wsgi_environ.get(attr):
+            attributes[f"wsgi_environ.{attr}"] = wsgi_environ[attr]
+
+    return attributes