Merge pull request #9 from csfreak/add_health_check

Add health check

Author: arnarg

.github/workflows/release.yml

@@ -15,7 +15,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v1
         with:
-          go-version: 1.13.x
+          go-version: 1.14.x
 
       - name: Docker login
         uses: azure/docker-login@v1

docker/Dockerfile

@@ -1,7 +1,7 @@
 FROM alpine:latest as certificates
 RUN apk update && apk add --no-cache ca-certificates && update-ca-certificates
 
-FROM golang:1.12 as builder
+FROM golang:1.14 as builder
 WORKDIR /build
 COPY . .
 RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -o /app/plex_exporter main.go

go.mod

@@ -1,8 +1,9 @@
 module github.com/arnarg/plex_exporter
 
-go 1.12
+go 1.14
 
 require (
+	github.com/alexliesenfeld/health v0.6.0
 	github.com/imdario/mergo v0.3.7
 	github.com/prometheus/client_golang v0.9.3
 	github.com/sirupsen/logrus v1.2.0

go.sum

@@ -1,12 +1,14 @@
-github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
+github.com/alexliesenfeld/health v0.6.0 h1:HRBTCgybNSe4lqGEk7nU82c3bjwh9W+3b46W6UvD4CQ=
+github.com/alexliesenfeld/health v0.6.0/go.mod h1:N4NDIeQtlWumG+6z1ne1v62eQxktz5ylEgGgH9emdMw=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/beorn7/perks v1.0.0 h1:HWo1m869IqiPhD389kmkxeTalrjNbbJTC8LXupb+sl0=
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
 github.com/cespare/xxhash v1.1.0/go.mod h1:XrSqR1VqqWfGrhpAt58auRo0WTKS1nRRg3ghfAqPWnc=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954/go.mod h1:vAd38F8PWV+bWy6jNmig1y/TA+kYO4g3RSRF0IAv0no=
@@ -47,12 +49,14 @@ github.com/prometheus/tsdb v0.7.1/go.mod h1:qhTCs0VvXwvX/y3TZrWD7rabWM+ijKTux40T
 github.com/sirupsen/logrus v1.2.0 h1:juTguoYk5qI21pwyTXY3B3Y5cOTH3ZUyZCg1v/mihuo=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
 github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.1.1 h1:2vfRuCMp5sSVIDSqO8oNnWJq7mPa6KVP3iPIwFBuy8A=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/urfave/cli v1.21.0 h1:wYSSj06510qPIzGSua9ZqsncMmWE3Zr55KBERygyrxE=
 github.com/urfave/cli v1.21.0/go.mod h1:lxDj6qX9Q6lWQxIrbrT0nwecwUtRnhVZAJjJZrVUZZQ=
-golang.org/x/crypto v0.0.0-20180904163835-0709b304e793 h1:u+LnwYTOOW7Ukr/fppxEb1Nwz0AtPflrblfvUudpo+I=
 golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2 h1:VklqNMn3ovrHsnt90PveolxSbWFaJdECFbxSq0Mqo2M=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
@@ -61,14 +65,14 @@ golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20181107165924-66b7b1311ac8/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20181116152217-5ac8a444bdc5 h1:mzjBh+S5frKOsOBobWIMAbXavqjmgO17k/2puhcFR94=
 golang.org/x/sys v0.0.0-20181116152217-5ac8a444bdc5/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a h1:1BGLXjeY4akVXGgbC9HugT3Jv3hCI0z56oJR5vAMgBU=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v2 v2.2.1 h1:mUhvW9EsL+naU5Q3cakzfE91YhliOondGd6ZrsDBHQE=
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

main.go

@@ -1,11 +1,13 @@
 package main
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 	"os"
 	"time"
 
+	"github.com/alexliesenfeld/health"
 	"github.com/arnarg/plex_exporter/collector"
 	"github.com/arnarg/plex_exporter/config"
 	"github.com/arnarg/plex_exporter/plex"
@@ -68,8 +70,36 @@ func Run(c *cli.Context) error {
 	pc := collector.NewPlexCollector(client, collectorLogger)
 	prometheus.MustRegister(pc)
 
+	//create health check
+	healhCheck := health.NewChecker(
+		health.WithCheck(health.Check{
+			Name:    "client",
+			Timeout: 2 * time.Second,
+			Check: func(ctx context.Context) error {
+				if len(client.Servers) > 0 {
+					return nil
+				}
+				return fmt.Errorf("No servers found")
+			},
+		}),
+		health.WithCheck(health.Check{
+			Name:    "servers",
+			Timeout: 2 * time.Second,
+			Check: func(ctx context.Context) error {
+				for _, server := range client.Servers {
+					_, err := server.GetServerInfo()
+					if err != nil {
+						return err
+					}
+				}
+				return nil
+			},
+		}),
+	)
+
 	// Start HTTP server
 	http.Handle("/metrics", promhttp.Handler())
+	http.Handle("/health", health.NewHandler(healhCheck))
 	log.Infof("Beginning to serve on port %s", conf.ListenAddress)
 	log.Fatal(http.ListenAndServe(conf.ListenAddress, nil))
 	return nil

plex/server.go

@@ -43,7 +43,7 @@ func NewServer(c config.PlexServerConfig) (*Server, error) {
 	}
 	server.headers["X-Plex-Token"] = c.Token
 
-	serverInfo, err := server.getServerInfo()
+	serverInfo, err := server.GetServerInfo()
 	if err != nil {
 		return nil, err
 	}
@@ -56,7 +56,7 @@ func NewServer(c config.PlexServerConfig) (*Server, error) {
 	return server, nil
 }
 
-func (s *Server) getServerInfo() (*api.ServerInfoResponse, error) {
+func (s *Server) GetServerInfo() (*api.ServerInfoResponse, error) {
 	serverInfoResponse := api.ServerInfoResponse{}
 
 	body, err := s.get(fmt.Sprintf(ServerInfoURI, s.BaseURL))