Log SystemExit (with non-zero exit code) and KeyboardInterrupt in WSG…

…I middleware

Neither SystemExit nor KeyboardInterrupt subclass Exception, so we must
explicitly handle these two exception classes in addition to Exception in the
WSGI middleware.

This is notably a direct port from raven-python:
 - https://github.com/getsentry/raven-python/blob/master/raven/middleware.py
 - https://github.com/getsentry/raven-python/blob/master/tests/middleware/tests.py

Fixes: getsentryGH-379

sentry_sdk/integrations/wsgi.py

@@ -89,6 +89,10 @@ def __call__(self, environ, start_response):
                 rv = self.app(environ, start_response)
             except Exception:
                 reraise(*_capture_exception(hub))
+            except KeyboardInterrupt:
+                reraise(*_capture_exception(self._hub))
+            except SystemExit as e:
+                reraise(*_capture_exception(self._hub, skip_capture=e.code == 0))
 
         return _ScopedResponse(hub, rv)
 
@@ -149,7 +153,7 @@ def get_client_ip(environ):
     return environ.get("REMOTE_ADDR")
 
 
-def _capture_exception(hub):
+def _capture_exception(hub, skip_capture=False):
     # type: (Hub) -> ExcInfo
     # Check client here as it might have been unset while streaming response
     if hub.client is not None:
@@ -159,7 +163,8 @@ def _capture_exception(hub):
             client_options=hub.client.options,
             mechanism={"type": "wsgi", "handled": False},
         )
-        hub.capture_event(event, hint=hint)
+        if not skip_capture:
+            hub.capture_event(event, hint=hint)
     return exc_info
 
 
@@ -183,6 +188,10 @@ def __iter__(self):
                     break
                 except Exception:
                     reraise(*_capture_exception(self._hub))
+                except KeyboardInterrupt:
+                    reraise(*_capture_exception(self._hub))
+                except SystemExit as e:
+                    reraise(*_capture_exception(self._hub, skip_capture=e.code == 0))
 
             yield chunk
 
@@ -194,6 +203,10 @@ def close(self):
                 pass
             except Exception:
                 reraise(*_capture_exception(self._hub))
+            except KeyboardInterrupt:
+                reraise(*_capture_exception(self._hub))
+            except SystemExit as e:
+                reraise(*_capture_exception(self._hub, skip_capture=e.code == 0))
 
 
 def _make_wsgi_event_processor(environ):

tests/integrations/wsgi/test_wsgi.py

@@ -1,3 +1,5 @@
+import logging
+
 from werkzeug.test import Client
 import pytest
 
@@ -12,6 +14,28 @@ def app(environ, start_response):
     return app
 
 
+class IterableApp(object):
+    def __init__(self, iterable):
+        self.iterable = iterable
+
+    def __call__(self, environ, start_response):
+        return self.iterable
+
+
+class ExitingIterable(object):
+    def __init__(self, exc_func):
+        self._exc_func = exc_func
+
+    def __iter__(self):
+        return self
+
+    def __next__(self):
+        raise self._exc_func()
+
+    def next(self):
+        return type(self).__next__(self)
+
+
 def test_basic(sentry_init, crashing_app, capture_events):
     sentry_init(send_default_pii=True)
     app = SentryWsgiMiddleware(crashing_app)
@@ -30,3 +54,54 @@ def test_basic(sentry_init, crashing_app, capture_events):
         "query_string": "",
         "url": "http://localhost/",
     }
+
+
+def test_systemexit_0_is_ignored(sentry_init, capture_events):
+    sentry_init(send_default_pii=True)
+    iterable = ExitingIterable(lambda: SystemExit(0))
+    app = SentryWsgiMiddleware(IterableApp(iterable))
+    client = Client(app)
+    events = capture_events()
+
+    with pytest.raises(SystemExit):
+        client.get("/")
+
+    assert len(events) == 0
+
+
+def test_systemexit_1_is_captured(sentry_init, capture_events):
+    sentry_init(send_default_pii=True)
+    iterable = ExitingIterable(lambda: SystemExit(1))
+    app = SentryWsgiMiddleware(IterableApp(iterable))
+    client = Client(app)
+    events = capture_events()
+
+    with pytest.raises(SystemExit):
+        client.get("/")
+
+    event, = events
+
+    assert "exception" in event
+    exc = event["exception"]["values"][-1]
+    assert exc["type"] == "SystemExit"
+    assert exc["value"] == "1"
+    assert event["level"] == "error"
+
+
+def test_keyboard_interrupt_is_captured(sentry_init, capture_events):
+    sentry_init(send_default_pii=True)
+    iterable = ExitingIterable(lambda: KeyboardInterrupt())
+    app = SentryWsgiMiddleware(IterableApp(iterable))
+    client = Client(app)
+    events = capture_events()
+
+    with pytest.raises(KeyboardInterrupt):
+        client.get("/")
+
+    event, = events
+
+    assert "exception" in event
+    exc = event["exception"]["values"][-1]
+    assert exc["type"] == "KeyboardInterrupt"
+    assert exc["value"] == ""
+    assert event["level"] == "error"