feat(middleware): Enable viewer context middleware by default

[gricha]

Enable the ViewerContextMiddleware by setting the viewer-context.enabled
option default to True. This causes the middleware to populate a
ViewerContext (unified caller identity) on every authenticated request.

The option uses FLAG_NOSTORE so the value is read at process startup from
deploy config (SENTRY_OPTIONS). Changing the default here means it will be
active everywhere unless explicitly overridden to False in deploy config.

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

Bugbot Autofix prepared a fix for the issue found in the latest run.

• ✅ Fixed: Default change breaks test relying on old default
  • Added @override_options decorator to explicitly set viewer-context.enabled to False in test_skipped_when_disabled, ensuring the test correctly validates disabled middleware behavior.

Or push these changes by commenting:

@cursor push 62bac19e44

Preview (62bac19e44)

diff --git a/tests/sentry/middleware/test_viewer_context.py b/tests/sentry/middleware/test_viewer_context.py
--- a/tests/sentry/middleware/test_viewer_context.py
+++ b/tests/sentry/middleware/test_viewer_context.py
@@ -103,6 +103,7 @@
         super().setUp()
         self.factory = RequestFactory()
 
+    @override_options({"viewer-context.enabled": False})
     def test_skipped_when_disabled(self):
         captured: list = []
 
@@ -110,7 +111,6 @@
             captured.append(get_viewer_context())
             return MagicMock(status_code=200)
 
-        # Default: viewer-context.enabled is False
         middleware = ViewerContextMiddleware(get_response)
 
         request = self.factory.get("/")

_{This Bugbot Autofix run was free. To enable autofix for future PRs, go to the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit fa5498b. Configure here.}

[github-actions]

Backend Test Failures

Failures on c7f2a76 in this run:

tests/sentry/web/frontend/generic/test_static_media.py::StaticMediaTest::test_no_cors — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/web/frontend/generic/test_static_media.py:96: in test_no_cors
    assert response["Vary"] == "Accept-Encoding"
E   AssertionError: assert 'Accept-Encoding, Cookie' == 'Accept-Encoding'
E     
E     - Accept-Encoding
E     + Accept-Encoding, Cookie
E     ?                ++++++++

tests/sentry/web/frontend/generic/test_static_media.py::StaticMediaTest::test_versioned — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/web/frontend/generic/test_static_media.py:30: in test_versioned
    assert response["Vary"] == "Accept-Encoding"
E   AssertionError: assert 'Accept-Encoding, Cookie' == 'Accept-Encoding'
E     
E     - Accept-Encoding
E     + Accept-Encoding, Cookie
E     ?                ++++++++

tests/sentry/web/frontend/test_organization_avatar.py::OrganizationAvatarTest::test_headers — log

[gw1] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/web/frontend/test_organization_avatar.py:22: in test_headers
    assert response.get("Vary") is None
E   assert 'Cookie' is None
E    +  where 'Cookie' = <bound method HttpResponseBase.get of <HttpResponse status_code=200, "image/png">>('Vary')
E    +    where <bound method HttpResponseBase.get of <HttpResponse status_code=200, "image/png">> = <HttpResponse status_code=200, "image/png">.get

tests/sentry/web/frontend/generic/test_static_media.py::StaticMediaTest::test_basic — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/web/frontend/generic/test_static_media.py:19: in test_basic
    assert response["Vary"] == "Accept-Encoding"
E   AssertionError: assert 'Accept-Encoding, Cookie' == 'Accept-Encoding'
E     
E     - Accept-Encoding
E     + Accept-Encoding, Cookie
E     ?                ++++++++

tests/sentry/web/frontend/generic/test_static_media.py::StaticMediaTest::test_frontend_app_assets — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/web/frontend/generic/test_static_media.py:72: in test_frontend_app_assets
    assert response["Vary"] == "Accept-Encoding"
E   AssertionError: assert 'Accept-Encoding, Cookie' == 'Accept-Encoding'
E     
E     - Accept-Encoding
E     + Accept-Encoding, Cookie
E     ?                ++++++++

tests/sentry/web/frontend/generic/test_static_media.py::StaticMediaTest::test_gzip — log

[gw1] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/web/frontend/generic/test_static_media.py:110: in test_gzip
    assert response["Vary"] == "Accept-Encoding"
E   AssertionError: assert 'Accept-Encoding, Cookie' == 'Accept-Encoding'
E     
E     - Accept-Encoding
E     + Accept-Encoding, Cookie
E     ?                ++++++++

tests/sentry/web/frontend/test_organization_avatar.py::OrganizationAvatarTest::test_origin_header — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/web/frontend/test_organization_avatar.py:35: in test_origin_header
    assert response.get("Vary") is None
E   assert 'Cookie' is None
E    +  where 'Cookie' = <bound method HttpResponseBase.get of <HttpResponse status_code=200, "image/png">>('Vary')
E    +    where <bound method HttpResponseBase.get of <HttpResponse status_code=200, "image/png">> = <HttpResponse status_code=200, "image/png">.get

tests/sentry/users/web/test_user_avatar.py::UserAvatarTest::test_headers_control_file — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/users/web/test_user_avatar.py:24: in test_headers_control_file
    assert response.get("Vary") is None
E   assert 'Cookie' is None
E    +  where 'Cookie' = <bound method HttpResponseBase.get of <HttpResponse status_code=200, "image/png">>('Vary')
E    +    where <bound method HttpResponseBase.get of <HttpResponse status_code=200, "image/png">> = <HttpResponse status_code=200, "image/png">.get

tests/sentry/web/frontend/test_js_sdk_loader.py::JavaScriptSdkLoaderTest::test_headers — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/web/frontend/test_js_sdk_loader.py:452: in test_headers
    assert "Vary" not in resp, f"Found Vary header: {resp['Vary']}"
E   AssertionError: Found Vary header: Cookie
E   assert 'Vary' not in <HttpResponse status_code=200, "text/javascript">