Add /api/metrics/prometheus endpoint

router/router.go

@@ -11,6 +11,7 @@ import (
 	"github.com/drone/drone/router/middleware/token"
 	"github.com/drone/drone/server"
 	"github.com/drone/drone/server/debug"
+	"github.com/drone/drone/server/metrics"
 	"github.com/drone/drone/server/template"
 
 	"github.com/drone/drone-ui/dist"
@@ -171,6 +172,14 @@ func Load(middleware ...gin.HandlerFunc) http.Handler {
 		debugger.GET("/pprof/trace", debug.TraceHandler())
 	}
 
+	monitor := e.Group("/api/metrics")
+	{
+		monitor.GET("/prometheus",
+			session.MustAdmin(),
+			metrics.PromHandler(),
+		)
+	}
+
 	return e
 }
 

server/metrics/prometheus.go

@@ -0,0 +1,14 @@
+package metrics
+
+import (
+	"github.com/gin-gonic/gin"
+
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+// PromHandler will pass the call from /api/metrics/prometheus to prometheus
+func PromHandler() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		promhttp.Handler().ServeHTTP(c.Writer, c.Request)
+	}
+}