fix(metrics): restore Prometheus scraping broken by FallbackPolicy#23
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…8e5ca2) 28e5ca2 ("security fixes") introduced `FallbackPolicy = RequireAuthenticatedUser`, which requires every endpoint to have an authenticated principal. Since `MapPrometheusScrapingEndpoint()` has no `[AllowAnonymous]` and `MetricsAuthenticationMiddleware` was registered after `UseAuthorization`, the authorization middleware rejected all unauthenticated scrape requests with 401 before the metrics middleware ever ran — making both `RequireAuthForMetrics=false` (public metrics) and `=true` (API key) non-functional. Three changes to fix this: 1. Program.cs: Move `MetricsAuthenticationMiddleware` to before `UseAuthorization` so it can set context.User before the FallbackPolicy is evaluated. 2. MetricsAuthenticationMiddleware.cs: Set `context.User` to a synthetic "prometheus-scraper" principal in both the public path (RequireAuthForMetrics=false) and the authenticated path (valid API key), satisfying RequireAuthenticatedUser without a session cookie. 3. AuthenticationHelper.cs: Accept `Authorization: Bearer <key>` as an alternative to the `X-Api-Key` header, matching the standard Prometheus `authorization:` scrape_config block documented in the README.
The env var is a default fallback only — once the toggle is saved via the UI, the persisted state.json value takes priority and the env var has no effect. Document this in the Security config table and add a troubleshooting entry with two fix paths (UI toggle and direct state.json edit).
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28e5ca2 ("security fixes") introduced
FallbackPolicy = RequireAuthenticatedUser, which requires every endpoint to have an authenticated principal.Since
MapPrometheusScrapingEndpoint()has no[AllowAnonymous]andMetricsAuthenticationMiddlewarewas registered afterUseAuthorization, the authorization middleware rejected all unauthenticated scrape requests with 401 before the metrics middleware ever ran — making bothRequireAuthForMetrics=false(public metrics) and=true(API key) non-functional.Three changes to fix this:
MetricsAuthenticationMiddlewareto beforeUseAuthorizationso it can set context.User before the FallbackPolicy is evaluated.context.Userto a synthetic "prometheus-scraper" principal in both the public path (RequireAuthForMetrics=false) and the authenticated path (valid API key), satisfying RequireAuthenticatedUser without a session cookie.Authorization: Bearer <key>as an alternativeto theX-Api-Keyheader, matching the standard Prometheusauthorization:scrape_config block documented in the README.