api: use alerting headers (#95118)

* api: use alerting headers

* improve code, add integration test

* better comment

* fixed test

* merged tests

pkg/services/pluginsintegration/clientmiddleware/usealertingheaders_middleware_test.go

@@ -0,0 +1,70 @@
+package clientmiddleware
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+	"github.com/grafana/grafana-plugin-sdk-go/backend/handlertest"
+	"github.com/grafana/grafana/pkg/services/user"
+	"github.com/stretchr/testify/require"
+)
+
+func TestUserAlertingHeadersMiddleware(t *testing.T) {
+	testQueryDataReq := func(t *testing.T, req *http.Request) *backend.QueryDataRequest {
+		cdt := handlertest.NewHandlerMiddlewareTest(t,
+			WithReqContext(req, &user.SignedInUser{}),
+			handlertest.WithMiddlewares(NewUseAlertHeadersMiddleware()),
+		)
+
+		pluginCtx := backend.PluginContext{
+			DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{},
+		}
+
+		_, err := cdt.MiddlewareHandler.QueryData(req.Context(), &backend.QueryDataRequest{
+			PluginContext: pluginCtx,
+			Headers:       map[string]string{},
+		})
+		require.NoError(t, err)
+		return cdt.QueryDataReq
+	}
+
+	t.Run("Handle non-alerting case without problems", func(t *testing.T) {
+		req, err := http.NewRequest(http.MethodGet, "/some/thing", nil)
+		require.NoError(t, err)
+		outReq := testQueryDataReq(t, req)
+
+		// special marker
+		require.Equal(t, "", outReq.Headers["FromAlert"])
+
+		// the normal http headers
+		require.Equal(t, "", outReq.GetHTTPHeader("X-Rule-Name"))
+		require.Equal(t, "", outReq.GetHTTPHeader("X-Rule-Folder"))
+		require.Equal(t, "", outReq.GetHTTPHeader("X-Rule-Source"))
+		require.Equal(t, "", outReq.GetHTTPHeader("X-Rule-Type"))
+		require.Equal(t, "", outReq.GetHTTPHeader("X-Rule-Version"))
+	})
+
+	t.Run("Use Alerting headers when they exist", func(t *testing.T) {
+		req, err := http.NewRequest(http.MethodGet, "/some/thing", nil)
+		require.NoError(t, err)
+		req.Header.Set("Fromalert", "true")
+		req.Header.Set("X-Rule-Name", "n1")
+		req.Header.Set("X-Rule-Folder", "f1")
+		req.Header.Set("X-Rule-Source", "s1")
+		req.Header.Set("X-Rule-Type", "t1")
+		req.Header.Set("X-Rule-Version", "v1")
+
+		outReq := testQueryDataReq(t, req)
+
+		// special marker
+		require.Equal(t, "true", outReq.Headers["FromAlert"])
+
+		// normal http headers
+		require.Equal(t, "n1", outReq.GetHTTPHeader("X-Rule-Name"))
+		require.Equal(t, "f1", outReq.GetHTTPHeader("X-Rule-Folder"))
+		require.Equal(t, "s1", outReq.GetHTTPHeader("X-Rule-Source"))
+		require.Equal(t, "t1", outReq.GetHTTPHeader("X-Rule-Type"))
+		require.Equal(t, "v1", outReq.GetHTTPHeader("X-Rule-Version"))
+	})
+}