Added prometheus metrics tracking

cmd/query-service/main.go

 package main
 
 import (
+	"log"
+	"net/http"
 	"query-service/internal/drivers/rpcdriver"
 	"query-service/internal/usecases/consume"
 	"query-service/internal/usecases/databaseinfo"
@@ -11,6 +13,7 @@ import (
 	"git.science.uu.nl/datastrophe/keyvaluestore"
 	"git.science.uu.nl/datastrophe/query-conversion/aql"
 	"git.science.uu.nl/datastrophe/query-execution/arangodb"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/thijsheijden/alice"
 )
 
@@ -45,5 +48,10 @@ func main() {
 
 	go consumeService.Start()
 
+	// Expose /metrics endpoint for prometheus
+	logger.Log("Starting metrics server")
+	http.Handle("/metrics", promhttp.Handler())
+	log.Fatal(http.ListenAndServe(":8080", nil))
+
 	select {}
 }

deployments/deployment.yml

 apiVersion: apps/v1
 kind: Deployment
 metadata:
-  name: query-handler
+  name: query-service
   labels:
     app: query-service
+    monitor: go-service
 spec:
   replicas: 1 
   selector:
     matchLabels:
       app: query-service
+      monitor: go-service
   template:
     metadata:
       labels:
-        app: query-service 
+        app: query-service
+        monitor: go-service
     spec:
       containers:
       - name: query-service
         image: datastropheregistry.azurecr.io/query-service:latest
         ports:
-        - containerPort: 3000 
+        - containerPort: 8080
         env:
         - name: RABBIT_HOST
           value: rabbitmq

deployments/svc.yml

@@ -7,5 +7,6 @@ spec:
   selector:
     app: query-service
   ports:
-    - port: 3000
-      targetPort: 3000
\ No newline at end of file
+    - name: monitoring
+      port: 8080
+      targetPort: 8080
\ No newline at end of file

go.mod

@@ -7,14 +7,11 @@ require (
 	git.science.uu.nl/datastrophe/keyvaluestore v0.0.0-20210517170603-34902cd5c90d
 	git.science.uu.nl/datastrophe/query-conversion v0.0.0-20210518093948-06ff65cdf577
 	git.science.uu.nl/datastrophe/query-execution v0.0.0-20210518112715-043c7046dc7b
-	github.com/arangodb/go-driver v0.0.0-20210518064911-4985e8be3d90
-	github.com/boumenot/gocover-cobertura v1.1.0 // indirect
+	github.com/prometheus/client_golang v1.10.0
 	github.com/stretchr/testify v1.7.0
 	github.com/thijsheijden/alice v0.1.18
-	golang.org/x/lint v0.0.0-20210508222113-6edffad5e616 // indirect
 	golang.org/x/net v0.0.0-20210510120150-4163338589ed // indirect
 	golang.org/x/sys v0.0.0-20210514084401-e8d321eab015 // indirect
-	golang.org/x/tools v0.1.1 // indirect
 	google.golang.org/grpc v1.37.1
 	google.golang.org/protobuf v1.26.0
 )