Support for Prometheus SD

.gitignore

@@ -1,3 +1,5 @@
 tmp/
 __debug*
 main
+bin/
+nodes.json

.vscode/launch.json

@@ -29,7 +29,7 @@
             "env": {
                 "DUMP_PATH": "../tmp/nodes.json",
                 "CONFIG_PATH": "../tmp/config.json",
-                "NODE_PATH": "../tmp/node"
+                "NODE_PATH": "../tmp/node.json"
             },
             "args": [
                 "node"

Taskfile.yml

@@ -20,3 +20,8 @@ tasks:
     - go mod tidy
     - mkdir -p bin
     - env CGO_ENABLED=0 go build -o bin/lobby2-{{ .VERSION }}-linux-amd64 cli/*.go
+  deploy:
+    cmds:
+    - task: build
+    - scp bin/lobby2-{{ .VERSION }}-linux-amd64 rosti-db:/usr/local/bin/lobby2.tmp
+    - ssh rosti-db mv /usr/local/bin/lobby2.tmp /usr/local/bin/lobby2

api/main.go

@@ -3,7 +3,6 @@ package api
 import (
 	"log"
 	"net/http"
-	"strings"
 
 	_ "gitea.ceperka.net/rosti/lobby2/docs" // This line is necessary for swag to find your docs!
 	"gitea.ceperka.net/rosti/lobby2/nodes"
@@ -120,30 +119,11 @@ func (a *API) refreshHandler(c echo.Context) error {
 // @Success 200 {array} []prometheusDiscovery "Node details"
 // @Failure 401 {object} Message "Forbidden access"
 // @Security Bearer
-// @Router /nodes/{hostname} [get]
+// @Router /prometheus/{service} [get]
 func (a *API) prometheusHandler(c echo.Context) error {
-	ss := c.QueryParam("service")
+	ss := c.Param("service")
 
-	ns := a.np.List()
-
-	pds := []prometheusDiscovery{
-		{
-			Labels:  nodes.Labels{},
-			Targets: []string{},
-		},
-	}
-
-	for _, node := range ns {
-		v, ok := node.KV["prometheus_exporters"]
-		if ok {
-			services := strings.Split(v, ",")
-			for _, service := range services {
-				if ss == service {
-					pds[0].Targets = append(pds[0].Targets, node.HostName)
-				}
-			}
-		}
-	}
+	pds := nodes.GetPrometheusSD(a.np, ss)
 
 	return c.JSONPretty(http.StatusOK, pds, "  ")
 }

api/types.go

@@ -10,8 +10,3 @@ type params struct {
 	Labels nodes.Labels `json:"labels"`
 	KV     nodes.KV     `json:"kv"`
 }
-
-type prometheusDiscovery struct {
-	Labels  nodes.Labels `json:"labels"`
-	Targets []string     `json:"targets"`
-}

cli/actions.go

@@ -52,3 +52,23 @@ func printAction(c *cli.Context) error {
 
 	return nil
 }
+
+func prometheusAction(c *cli.Context) error {
+	cfg := GetConfig()
+
+	np := nodes.NewNodesProcessor(cfg.DumpPath, cfg.DropAfterSeconds)
+
+	pds := nodes.GetPrometheusSD(np, "node")
+
+	for _, pd := range pds {
+		body, err := json.MarshalIndent(pd, "", "  ")
+		if err != nil {
+			fmt.Printf("failed to marshal prometheus discovery: %v\n", err)
+			os.Exit(1)
+		}
+
+		fmt.Println(string(body))
+	}
+
+	return nil
+}

cli/main.go

@@ -27,6 +27,11 @@ func main() {
 				Usage:  "Prints all discovered nodes",
 				Action: printAction,
 			},
+			{
+				Name:   "prometheus",
+				Usage:  "Prints Prometheus Service Discovery",
+				Action: prometheusAction,
+			},
 		},
 	}
 

nodes/prometheus.go

@@ -0,0 +1,45 @@
+package nodes
+
+import (
+	"fmt"
+	"strings"
+)
+
+type prometheusDiscovery struct {
+	Labels  Labels   `json:"Labels"`
+	Targets []string `json:"Targets"`
+}
+
+func GetPrometheusSD(p *NodesProcessor, ss string) []prometheusDiscovery {
+	ns := p.List()
+
+	pds := []prometheusDiscovery{
+		{
+			Labels:  Labels{},
+			Targets: []string{},
+		},
+	}
+
+	for _, node := range ns {
+		port, ok := node.KV["prometheus_port"]
+		if !ok {
+			port = "9999"
+		}
+		host, ok := node.KV["prometheus_host"]
+		if !ok {
+			host = node.HostName
+		}
+
+		v, ok := node.KV["prometheus_exporters"]
+		if ok {
+			services := strings.Split(v, ",")
+			for _, service := range services {
+				if ss == service {
+					pds[0].Targets = append(pds[0].Targets, fmt.Sprintf("%s:%s", host, port))
+				}
+			}
+		}
+	}
+
+	return pds
+}