feat(django): Add SpotlightMiddleware when Spotlight is enabled (#3600)

BYK · web-flow · commit 00f8140d55dc · 2024-10-04T15:20:34.000+02:00
This patch replaces Django's debug error page with Spotlight when
it is enabled and is running. It bails when DEBUG is False,
when it cannot connect to the Spotlight web server, or when
explicitly turned off with SENTRY_SPOTLIGHT_ON_ERROR=0.
diff --git a/sentry_sdk/client.py b/sentry_sdk/client.py
@@ -61,6 +61,7 @@
     from sentry_sdk.metrics import MetricsAggregator
     from sentry_sdk.scope import Scope
     from sentry_sdk.session import Session
+    from sentry_sdk.spotlight import SpotlightClient
     from sentry_sdk.transport import Transport
 
     I = TypeVar("I", bound=Integration)  # noqa: E741
@@ -153,6 +154,8 @@ class BaseClient:
     The basic definition of a client that is used for sending data to Sentry.
     """
 
+    spotlight = None  # type: Optional[SpotlightClient]
+
     def __init__(self, options=None):
         # type: (Optional[Dict[str, Any]]) -> None
         self.options = (
@@ -385,7 +388,6 @@ def _capture_envelope(envelope):
                 disabled_integrations=self.options["disabled_integrations"],
             )
 
-            self.spotlight = None
             spotlight_config = self.options.get("spotlight")
             if spotlight_config is None and "SENTRY_SPOTLIGHT" in os.environ:
                 spotlight_env_value = os.environ["SENTRY_SPOTLIGHT"]
diff --git a/sentry_sdk/spotlight.py b/sentry_sdk/spotlight.py
@@ -1,14 +1,19 @@
 import io
+import os
+import urllib.parse
+import urllib.request
+import urllib.error
 import urllib3
 
 from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
     from typing import Any
+    from typing import Callable
     from typing import Dict
     from typing import Optional
 
-from sentry_sdk.utils import logger
+from sentry_sdk.utils import logger, env_to_bool
 from sentry_sdk.envelope import Envelope
 
 
@@ -46,6 +51,47 @@ def capture_envelope(self, envelope):
             logger.warning(str(e))
 
 
+try:
+    from django.http import HttpResponseServerError
+    from django.conf import settings
+
+    class SpotlightMiddleware:
+        def __init__(self, get_response):
+            # type: (Any, Callable[..., Any]) -> None
+            self.get_response = get_response
+
+        def __call__(self, request):
+            # type: (Any, Any) -> Any
+            return self.get_response(request)
+
+        def process_exception(self, _request, exception):
+            # type: (Any, Any, Exception) -> Optional[HttpResponseServerError]
+            if not settings.DEBUG:
+                return None
+
+            import sentry_sdk.api
+
+            spotlight_client = sentry_sdk.api.get_client().spotlight
+            if spotlight_client is None:
+                return None
+
+            # Spotlight URL has a trailing `/stream` part at the end so split it off
+            spotlight_url = spotlight_client.url.rsplit("/", 1)[0]
+
+            try:
+                spotlight = (
+                    urllib.request.urlopen(spotlight_url).read().decode("utf-8")
+                ).replace("<html>", f'<html><base href="{spotlight_url}">')
+            except urllib.error.URLError:
+                return None
+            else:
+                sentry_sdk.api.capture_exception(exception)
+                return HttpResponseServerError(spotlight)
+
+except ImportError:
+    settings = None
+
+
 def setup_spotlight(options):
     # type: (Dict[str, Any]) -> Optional[SpotlightClient]
 
@@ -58,4 +104,9 @@ def setup_spotlight(options):
     else:
         return None
 
+    if settings is not None and env_to_bool(
+        os.environ.get("SENTRY_SPOTLIGHT_ON_ERROR", "1")
+    ):
+        settings.MIDDLEWARE.append("sentry_sdk.spotlight.SpotlightMiddleware")
+
     return SpotlightClient(url)
diff --git a/tests/integrations/django/test_basic.py b/tests/integrations/django/test_basic.py
@@ -1240,3 +1240,54 @@ def test_transaction_http_method_custom(sentry_init, client, capture_events):
     (event1, event2) = events
     assert event1["request"]["method"] == "OPTIONS"
     assert event2["request"]["method"] == "HEAD"
+
+
+def test_ensures_spotlight_middleware_when_spotlight_is_enabled(sentry_init, settings):
+    """
+    Test that ensures if Spotlight is enabled, relevant SpotlightMiddleware
+    is added to middleware list in settings.
+    """
+    original_middleware = frozenset(settings.MIDDLEWARE)
+
+    sentry_init(integrations=[DjangoIntegration()], spotlight=True)
+
+    added = frozenset(settings.MIDDLEWARE) ^ original_middleware
+
+    assert "sentry_sdk.spotlight.SpotlightMiddleware" in added
+
+
+def test_ensures_no_spotlight_middleware_when_env_killswitch_is_false(
+    monkeypatch, sentry_init, settings
+):
+    """
+    Test that ensures if Spotlight is enabled, but is set to a falsy value
+    the relevant SpotlightMiddleware is NOT added to middleware list in settings.
+    """
+    monkeypatch.setenv("SENTRY_SPOTLIGHT_ON_ERROR", "no")
+
+    original_middleware = frozenset(settings.MIDDLEWARE)
+
+    sentry_init(integrations=[DjangoIntegration()], spotlight=True)
+
+    added = frozenset(settings.MIDDLEWARE) ^ original_middleware
+
+    assert "sentry_sdk.spotlight.SpotlightMiddleware" not in added
+
+
+def test_ensures_no_spotlight_middleware_when_no_spotlight(
+    monkeypatch, sentry_init, settings
+):
+    """
+    Test that ensures if Spotlight is not enabled
+    the relevant SpotlightMiddleware is NOT added to middleware list in settings.
+    """
+    # We should NOT have the middleware even if the env var is truthy if Spotlight is off
+    monkeypatch.setenv("SENTRY_SPOTLIGHT_ON_ERROR", "1")
+
+    original_middleware = frozenset(settings.MIDDLEWARE)
+
+    sentry_init(integrations=[DjangoIntegration()], spotlight=False)
+
+    added = frozenset(settings.MIDDLEWARE) ^ original_middleware
+
+    assert "sentry_sdk.spotlight.SpotlightMiddleware" not in added
