From b1ddba9767a2987fee3dde75cb766225a9019ee7 Mon Sep 17 00:00:00 2001
From: Costa Alexoglou <konstantinos.alexoglou@grafana.com>
Date: Wed, 22 Oct 2025 22:20:41 +0200
Subject: [PATCH] docs: remove ai generated file (#112821)

---
 .../builder/CUSTOM_ROUTES_METRICS.md          | 162 ------------------
 1 file changed, 162 deletions(-)
 delete mode 100644 pkg/services/apiserver/builder/CUSTOM_ROUTES_METRICS.md

diff --git a/pkg/services/apiserver/builder/CUSTOM_ROUTES_METRICS.md b/pkg/services/apiserver/builder/CUSTOM_ROUTES_METRICS.md
deleted file mode 100644
index 00e26aea782..00000000000
--- a/pkg/services/apiserver/builder/CUSTOM_ROUTES_METRICS.md
+++ /dev/null
@@ -1,162 +0,0 @@
-## Custom Route Metrics in Grafana API Server
-
-### Problem
-
-Custom API routes registered via `APIGroupRouteProvider.GetAPIRoutes()` bypass the standard Kubernetes apiserver metrics recording middleware. Requests to these routes were not being recorded in `apiserver_request_total`.
-
-**Why this happens:**
-
-```
-HTTP Request
-    ↓
-Gorilla Mux (custom routes) 
-    ├─ [MATCHED] → Your custom handler → Response ❌ (no metrics recorded)
-    │
-    └─ [NOT MATCHED] → k8s DefaultBuildHandlerChain
-                           ├─ WithRequestMetrics (records apiserver_request_total) ✅
-                           └─ Standard REST storage handlers
-```
-
-Custom routes are served by Gorilla Mux and return immediately, never reaching the k8s metrics middleware.
-
-### Solution
-
-We've implemented **centralized automatic instrumentation** that records custom route requests in the **same `apiserver_request_total` metric** used by standard Kubernetes API calls. This means:
-
-- ✅ **Single metric** for all API requests (standard + custom routes)
-- ✅ **Consistent labels** matching Kubernetes conventions
-- ✅ **No dashboard changes** needed - existing queries work
-- ✅ **Automatic** for all API servers with zero code changes
-
-#### Key Components
-
-1. **`pkg/services/apiserver/builder/custom_route_metrics.go`**
-   - Defines `CustomRouteMetrics` 
-   - Uses the existing `apiserver_request_total` metric (via `metrics.MonitorRequest`)
-   - Provides `responseWriterWithStatus` to capture HTTP status codes
-   - Provides `InstrumentHandler()` to wrap route handlers
-
-2. **`pkg/services/apiserver/builder/request_handler.go`**
-   - Updated `GetCustomRoutesHandler()` to accept `prometheus.Registerer`
-   - Automatically instruments ALL custom routes (both root and namespace)
-   - Works transparently for all API servers
-
-3. **Updated signatures**
-   - `BuildHandlerChainFuncFromBuilders`: now accepts `prometheus.Registerer`
-   - `GetDefaultBuildHandlerChainFunc`: now accepts `prometheus.Registerer`
-   - `SetupConfig`: now accepts `prometheus.Registerer`
-   - Factory interfaces updated to pass registry through
-
-### Usage
-
-**For new API servers:** No action required! Custom routes are automatically instrumented.
-
-**For existing API servers:** No changes needed. All API servers using `APIGroupRouteProvider` automatically get metrics.
-
-### Metrics
-
-Query in Prometheus - **same metric as standard API calls**:
-
-```promql
-# Total requests by status code (includes both standard REST and custom routes)
-sum by (code)(rate(apiserver_request_total{group="provisioning.grafana.app"}[$__rate_interval]))
-
-# Requests by resource and status
-sum by (resource, code)(rate(apiserver_request_total{group="provisioning.grafana.app"}[$__rate_interval]))
-
-# Error rate (4xx + 5xx)
-sum(rate(apiserver_request_total{group="provisioning.grafana.app", code=~"[45].."}[$__rate_interval]))
-/ 
-sum(rate(apiserver_request_total{group="provisioning.grafana.app"}[$__rate_interval]))
-
-# Custom routes specifically (filter by resource name)
-sum by (resource, code)(rate(apiserver_request_total{
-  group="provisioning.grafana.app",
-  resource=~"stats|settings"  # custom route resources
-}[$__rate_interval]))
-```
-
-### Example
-
-For a custom route like `/apis/provisioning.grafana.app/v0alpha1/namespaces/default/settings`:
-
-```go
-func (b *APIBuilder) GetAPIRoutes(gv schema.GroupVersion) *builder.APIRoutes {
-    return &builder.APIRoutes{
-        Namespace: []builder.APIRouteHandler{
-            {
-                Path: "settings",
-                Handler: b.handleSettings, // Automatically instrumented!
-            },
-        },
-    }
-}
-```
-
-Metrics recorded in `apiserver_request_total`:
-```
-apiserver_request_total{
-  verb="GET",
-  dry_run="",
-  group="provisioning.grafana.app",
-  version="v0alpha1",
-  resource="settings",
-  subresource="",
-  scope="namespace",
-  component="",
-  code="200"
-} 1
-
-apiserver_request_total{
-  verb="GET",
-  dry_run="",
-  group="provisioning.grafana.app",
-  version="v0alpha1",
-  resource="settings",
-  subresource="",
-  scope="namespace",
-  component="",
-  code="401"
-} 1
-```
-
-### Implementation Details
-
-The `responseWriterWithStatus` wrapper:
-- Wraps `http.ResponseWriter` to intercept `WriteHeader()` and `Write()` calls
-- Captures the status code before the response is sent
-- Defaults to 200 if `WriteHeader()` is never called
-- Works with `errhttp.Write()`, manual `WriteHeader()`, and implicit status codes
-
-### API Servers with Custom Routes
-
-Currently instrumented (as of October 2025):
-1. `provisioning.grafana.app` - stats, settings
-2. `querylibrary.grafana.app`
-3. `queries.grafana.app`
-4. `alertenrichment.grafana.app`
-5. `scim.grafana.app`
-6. `dashboard.grafana.app`
-7. `iam.grafana.app`
-8. `ofrep.grafana.app`
-9. `dashboardsnapshot.grafana.app`
-
-All of these automatically get metrics with no code changes required.
-
-### Testing
-
-To verify metrics are working:
-
-1. Make requests to custom routes
-2. Check Prometheus:
-   ```promql
-   apiserver_custom_route_requests_total
-   ```
-3. You should see metrics with proper status codes (200, 401, 404, 500, etc.)
-
-### Future Improvements
-
-- Add request duration histogram
-- Add request size histogram
-- Add response size histogram
-- Align label names with standard Kubernetes metrics