fix: add /health endpoint (#881)

* fix: add /health endpoint

go.mod

@@ -6,6 +6,7 @@ require (
 	entgo.io/ent v0.7.0
 	github.com/AlecAivazis/survey/v2 v2.2.7
 	github.com/Microsoft/go-winio v0.4.16 // indirect
+	github.com/alexliesenfeld/health v0.5.1
 	github.com/antonmedv/expr v1.8.9
 	github.com/appleboy/gin-jwt/v2 v2.6.4
 	github.com/aws/aws-sdk-go v1.38.34
@@ -32,7 +33,7 @@ require (
 	github.com/google/go-querystring v1.0.0
 	github.com/goombaio/namegenerator v0.0.0-20181006234301-989e774b106e
 	github.com/hashicorp/go-version v1.2.1
-	github.com/influxdata/go-syslog/v3 v3.0.0 // indirect
+	github.com/influxdata/go-syslog/v3 v3.0.0
 	github.com/leodido/go-urn v1.2.1 // indirect
 	github.com/lib/pq v1.10.0
 	github.com/logrusorgru/grokky v0.0.0-20180829062225-47edf017d42c
@@ -63,7 +64,7 @@ require (
 	golang.org/x/crypto v0.0.0-20201221181555-eec23a3978ad
 	golang.org/x/mod v0.4.1
 	golang.org/x/net v0.0.0-20201224014010-6772e930b67b // indirect
-	golang.org/x/sys v0.0.0-20210503173754-0981d6026fa6 // indirect
+	golang.org/x/sys v0.0.0-20210503173754-0981d6026fa6
 	golang.org/x/term v0.0.0-20201210144234-2321bbc49cbf // indirect
 	golang.org/x/text v0.3.5 // indirect
 	google.golang.org/genproto v0.0.0-20210114201628-6edceaf6022f // indirect

go.sum

@@ -44,6 +44,8 @@ github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751/go.mod h1:LOuy
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
 github.com/alecthomas/units v0.0.0-20190717042225-c3de453c63f4/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
 github.com/alecthomas/units v0.0.0-20190924025748-f65c72e2690d/go.mod h1:rBZYJk541a8SKzHPHnH3zbiI+7dagKZ0cgpgrD7Fyho=
+github.com/alexliesenfeld/health v0.5.1 h1:cohQdtQbJdA6bj0aMD4gdXA9xQyvh9NxWO9XLGYTYcY=
+github.com/alexliesenfeld/health v0.5.1/go.mod h1:N4NDIeQtlWumG+6z1ne1v62eQxktz5ylEgGgH9emdMw=
 github.com/andreyvit/diff v0.0.0-20170406064948-c7f18ee00883/go.mod h1:rCTlJbsFo29Kk6CurOXKm700vrz8f0KW0JNfpkRJY/8=
 github.com/antonmedv/expr v1.8.9 h1:O9stiHmHHww9b4ozhPx7T6BK7fXfOCHJ8ybxf0833zw=
 github.com/antonmedv/expr v1.8.9/go.mod h1:5qsM3oLGDND7sDmQGDXHkYfkjYMUX14qsgqmHhwGEk8=
@@ -65,7 +67,6 @@ github.com/asaskevich/govalidator v0.0.0-20200907205600-7a23bdc65eef h1:46PFijGL
 github.com/asaskevich/govalidator v0.0.0-20200907205600-7a23bdc65eef/go.mod h1:WaHUgvxTVq04UNunO+XhnAqY/wQc+bxr74GqbsZ/Jqw=
 github.com/aws/aws-lambda-go v1.13.3/go.mod h1:4UKl9IzQMoD+QF79YdCuzCwp8VbmG4VAQwij/eHl5CU=
 github.com/aws/aws-sdk-go v1.27.0/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN924inxo=
-github.com/aws/aws-sdk-go v1.34.28 h1:sscPpn/Ns3i0F4HPEWAVcwdIRaZZCuL7llJ2/60yPIk=
 github.com/aws/aws-sdk-go v1.34.28/go.mod h1:H7NKnBqNVzoTJpGfLrQkkD+ytBA93eiDYi/+8rV9s48=
 github.com/aws/aws-sdk-go v1.38.34 h1:JSAyS6hSDLbRmCAz9VAkwDf5oh/olt9mBTrVBWGJcU8=
 github.com/aws/aws-sdk-go v1.38.34/go.mod h1:hcU610XS61/+aQV88ixoOzUoG7v3b31pl2zKMmprdro=
@@ -395,6 +396,7 @@ github.com/jessevdk/go-flags v1.4.0/go.mod h1:4FA24M0QyGHXBuZZK/XkWh8h0e1EYbRYJS
 github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=
 github.com/jmespath/go-jmespath v0.4.0 h1:BEgLn5cpjn8UN1mAw4NjwDrS35OdebyEtFe+9YPoQUg=
 github.com/jmespath/go-jmespath v0.4.0/go.mod h1:T8mJZnbsbmF+m6zOOFylbeCJqk5+pHWvzYPziyZiYoo=
+github.com/jmespath/go-jmespath/internal/testify v1.5.1 h1:shLQSRRSCCPj3f2gpwzGwWFoC7ycTf1rcQZHOlsJ6N8=
 github.com/jmespath/go-jmespath/internal/testify v1.5.1/go.mod h1:L3OGu8Wl2/fWfCI6z80xFu9LTZmf1ZRjMHUOPmWr69U=
 github.com/joho/godotenv v1.3.0/go.mod h1:7hK45KPybAkOC6peb+G5yklZfMxEjkZhHbwpqxOKXbg=
 github.com/jonboulle/clockwork v0.1.0/go.mod h1:Ii8DK3G1RaLaWxj9trq07+26W01tbo22gdxWY5EU2bo=
@@ -643,6 +645,7 @@ github.com/streadway/amqp v0.0.0-20190827072141-edfb9018d271/go.mod h1:AZpEONHx3
 github.com/streadway/handy v0.0.0-20190108123426-d5acb3125c2a/go.mod h1:qNTQ5P5JnDBl6z3cMAg/SywNDC5ABu5ApDIw6lUbRmI=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.2.0 h1:Hbg2NidpLE8veEBkEZTL3CvlkUIVzuU9jDplZO54c48=
 github.com/stretchr/objx v0.2.0/go.mod h1:qt09Ya8vawLte6SNmTgCsAVtYtaKzEcn8ATUoHMkEqE=
 github.com/stretchr/testify v0.0.0-20161117074351-18a02ba4a312/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.2.1/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
@@ -825,7 +828,6 @@ golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210309074719-68d13333faf2 h1:46ULzRKLh1CwgRq2dC5SlBzEqqNCi8rreOZnNrbqcIY=
 golang.org/x/sys v0.0.0-20210309074719-68d13333faf2/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210503173754-0981d6026fa6 h1:cdsMqa2nXzqlgs183pHxtvoVwU7CyzaCTAUOg94af4c=
 golang.org/x/sys v0.0.0-20210503173754-0981d6026fa6/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=

pkg/apiserver/controllers/controller.go

@@ -2,14 +2,14 @@ package controllers
 
 import (
 	"context"
-	"net/http"
-
+	"github.com/alexliesenfeld/health"
 	v1 "github.com/crowdsecurity/crowdsec/pkg/apiserver/controllers/v1"
 	"github.com/crowdsecurity/crowdsec/pkg/csconfig"
 	"github.com/crowdsecurity/crowdsec/pkg/database"
 	"github.com/crowdsecurity/crowdsec/pkg/models"
 	"github.com/gin-gonic/gin"
 	log "github.com/sirupsen/logrus"
+	"net/http"
 )
 
 type Controller struct {
@@ -37,12 +37,24 @@ func (c *Controller) Init() error {
 	return nil
 }
 
+// endpoint for health checking
+func serveHealth() http.HandlerFunc {
+	checker := health.NewChecker(
+		// just simple up/down status is enough
+		health.WithDisabledDetails(),
+		// no caching required
+		health.WithDisabledCache(),
+	)
+	return health.NewHandler(checker)
+}
+
 func (c *Controller) NewV1() error {
 	handlerV1, err := v1.New(c.DBClient, c.Ectx, c.Profiles, c.CAPIChan)
 	if err != nil {
 		return err
 	}
 
+	c.Router.GET("/health", gin.WrapF(serveHealth()))
 	c.Router.Use(v1.PrometheusMiddleware())
 	c.Router.HandleMethodNotAllowed = true
 	c.Router.NoRoute(func(ctx *gin.Context) {