remove gin completely, ~2MB reduction on final binary

app.go

@@ -17,17 +17,16 @@ import (
 	"time"
 
 	"github.com/coreos/go-oidc/v3/oidc"
-	"github.com/gin-gonic/gin"
 	"github.com/gorilla/mux"
 	grpc_middleware "github.com/grpc-ecosystem/go-grpc-middleware"
 	"github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
 	v1 "github.com/juanfont/headscale/gen/go/headscale/v1"
 	"github.com/patrickmn/go-cache"
 	zerolog "github.com/philip-bui/grpc-zerolog"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/puzpuzpuz/xsync"
 	zl "github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
-	ginprometheus "github.com/zsais/go-gin-prometheus"
 	"golang.org/x/crypto/acme"
 	"golang.org/x/crypto/acme/autocert"
 	"golang.org/x/oauth2"
@@ -411,15 +410,6 @@ func (h *Headscale) ensureUnixSocketIsAbsent() error {
 	return os.Remove(h.cfg.UnixSocket)
 }
 
-func (h *Headscale) createPrometheusRouter() *gin.Engine {
-	promRouter := gin.Default()
-
-	prometheus := ginprometheus.NewPrometheus("gin")
-	prometheus.Use(promRouter)
-
-	return promRouter
-}
-
 func (h *Headscale) createRouter(grpcMux *runtime.ServeMux) *mux.Router {
 	router := mux.NewRouter()
 
@@ -647,11 +637,12 @@ func (h *Headscale) Serve() error {
 	log.Info().
 		Msgf("listening and serving HTTP on: %s", h.cfg.Addr)
 
-	promRouter := h.createPrometheusRouter()
+	promMux := http.NewServeMux()
+	promMux.Handle("/metrics", promhttp.Handler())
 
 	promHTTPServer := &http.Server{
 		Addr:         h.cfg.MetricsAddr,
-		Handler:      promRouter,
+		Handler:      promMux,
 		ReadTimeout:  HTTPReadTimeout,
 		WriteTimeout: 0,
 	}

go.mod

@@ -8,7 +8,6 @@ require (
 	github.com/coreos/go-oidc/v3 v3.1.0
 	github.com/deckarep/golang-set/v2 v2.1.0
 	github.com/efekarakus/termcolor v1.0.1
-	github.com/gin-gonic/gin v1.7.7
 	github.com/glebarez/sqlite v1.4.3
 	github.com/gofrs/uuid v4.2.0+incompatible
 	github.com/gorilla/mux v1.8.0
@@ -28,7 +27,6 @@ require (
 	github.com/stretchr/testify v1.7.1
 	github.com/tailscale/hujson v0.0.0-20220506202205-92b4b88a9e17
 	github.com/tcnksm/go-latest v0.0.0-20170313132115-e3007ae9052e
-	github.com/zsais/go-gin-prometheus v0.1.0
 	golang.org/x/crypto v0.0.0-20220427172511-eb4f295cb31f
 	golang.org/x/oauth2 v0.0.0-20220411215720-9780585627b5
 	golang.org/x/sync v0.0.0-20220513210516-0976fa681c29
@@ -61,11 +59,7 @@ require (
 	github.com/docker/go-connections v0.4.0 // indirect
 	github.com/docker/go-units v0.4.0 // indirect
 	github.com/fsnotify/fsnotify v1.5.1 // indirect
-	github.com/gin-contrib/sse v0.1.0 // indirect
 	github.com/glebarez/go-sqlite v1.16.0 // indirect
-	github.com/go-playground/locales v0.13.0 // indirect
-	github.com/go-playground/universal-translator v0.17.0 // indirect
-	github.com/go-playground/validator/v10 v10.4.1 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/google/go-cmp v0.5.8 // indirect
@@ -90,11 +84,9 @@ require (
 	github.com/jinzhu/now v1.1.4 // indirect
 	github.com/josharian/native v1.0.0 // indirect
 	github.com/jsimonetti/rtnetlink v1.1.2-0.20220408201609-d380b505068b // indirect
-	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 // indirect
 	github.com/kr/pretty v0.3.0 // indirect
 	github.com/kr/text v0.2.0 // indirect
-	github.com/leodido/go-urn v1.2.0 // indirect
 	github.com/magiconair/properties v1.8.6 // indirect
 	github.com/mattn/go-colorable v0.1.12 // indirect
 	github.com/mattn/go-isatty v0.0.14 // indirect
@@ -106,8 +98,6 @@ require (
 	github.com/mitchellh/go-ps v1.0.0 // indirect
 	github.com/mitchellh/mapstructure v1.4.3 // indirect
 	github.com/moby/term v0.0.0-20201216013528-df9cb8a40635 // indirect
-	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
-	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/opencontainers/go-digest v1.0.0 // indirect
 	github.com/opencontainers/image-spec v1.0.3-0.20220114050600-8b9d41f48198 // indirect
 	github.com/opencontainers/runc v1.0.2 // indirect
@@ -126,7 +116,6 @@ require (
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/subosito/gotenv v1.2.0 // indirect
-	github.com/ugorji/go/codec v1.1.7 // indirect
 	github.com/xeipuuv/gojsonpointer v0.0.0-20180127040702-4e3ac2762d5f // indirect
 	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect
 	github.com/xeipuuv/gojsonschema v1.2.0 // indirect

go.sum

@@ -236,10 +236,6 @@ github.com/fsnotify/fsnotify v1.5.1/go.mod h1:T3375wBYaZdLLcVNkcVbzGHY7f1l/uK5T5
 github.com/fullstorydev/grpcurl v1.6.0/go.mod h1:ZQ+ayqbKMJNhzLmbpCiurTVlaK2M/3nqZCxaQ2Ze/sM=
 github.com/fzipp/gocyclo v0.3.1/go.mod h1:DJHO6AUmbdqj2ET4Z9iArSuwWgYDRryYt2wASxc7x3E=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
-github.com/gin-contrib/sse v0.1.0 h1:Y/yl/+YNO8GZSjAhjMsSuLt29uWRFHdHYUb5lYOV9qE=
-github.com/gin-contrib/sse v0.1.0/go.mod h1:RHrZQHXnP2xjPF+u1gW/2HnVO7nvIa9PG3Gm+fLHvGI=
-github.com/gin-gonic/gin v1.7.7 h1:3DoBmSbJbZAWqXJC3SLjAPfutPJJRN1U5pALB7EeTTs=
-github.com/gin-gonic/gin v1.7.7/go.mod h1:axIBovoeJpVj8S3BwE0uPMTeReE4+AfFtqpqaZ1qq1U=
 github.com/glebarez/go-sqlite v1.16.0 h1:h28rHued+hGof3fNLksBcLwz/a71fiGZ/eIJHK0SsLI=
 github.com/glebarez/go-sqlite v1.16.0/go.mod h1:i8/JtqoqzBAFkrUTxbQFkQ05odCOds3j7NlDaXjqiPY=
 github.com/glebarez/sqlite v1.4.3 h1:ZABNo+2YIau8F8sZ7Qh/1h/ZnlSUMHFGD4zJKPval7A=
@@ -256,14 +252,6 @@ github.com/go-logfmt/logfmt v0.4.0/go.mod h1:3RMwSq7FuexP4Kalkev3ejPJsZTpXXBr9+V
 github.com/go-logfmt/logfmt v0.5.0/go.mod h1:wCYkCAKZfumFQihp8CzCvQ3paCTfi41vtzG1KdI/P7A=
 github.com/go-ole/go-ole v1.2.5/go.mod h1:pprOEPIfldk/42T2oK7lQ4v4JSDwmV0As9GaiUsvbm0=
 github.com/go-ole/go-ole v1.2.6/go.mod h1:pprOEPIfldk/42T2oK7lQ4v4JSDwmV0As9GaiUsvbm0=
-github.com/go-playground/assert/v2 v2.0.1 h1:MsBgLAaY856+nPRTKrp3/OZK38U/wa0CcBYNjji3q3A=
-github.com/go-playground/assert/v2 v2.0.1/go.mod h1:VDjEfimB/XKnb+ZQfWdccd7VUvScMdVu0Titje2rxJ4=
-github.com/go-playground/locales v0.13.0 h1:HyWk6mgj5qFqCT5fjGBuRArbVDfE4hi8+e8ceBS/t7Q=
-github.com/go-playground/locales v0.13.0/go.mod h1:taPMhCMXrRLJO55olJkUXHZBHCxTMfnGwq/HNwmWNS8=
-github.com/go-playground/universal-translator v0.17.0 h1:icxd5fm+REJzpZx7ZfpaD876Lmtgy7VtROAbHHXk8no=
-github.com/go-playground/universal-translator v0.17.0/go.mod h1:UkSxE5sNxxRwHyU+Scu5vgOQjsIJAF8j9muTVoKLVtA=
-github.com/go-playground/validator/v10 v10.4.1 h1:pH2c5ADXtd66mxoE0Zm9SUhxE20r7aM3F26W0hOn+GE=
-github.com/go-playground/validator/v10 v10.4.1/go.mod h1:nlOn6nFhuKACm19sB/8EGNn9GlaMV7XkbRSipzJ0Ii4=
 github.com/go-redis/redis v6.15.8+incompatible/go.mod h1:NAIEuMOZ/fxfXJIrKDQDz8wamY7mA7PouImQ2Jvg6kA=
 github.com/go-sql-driver/mysql v1.4.0/go.mod h1:zAC/RDZ24gD3HViQzih4MyKcchzm+sOG5ZlKdlhCg5w=
 github.com/go-sql-driver/mysql v1.5.0/go.mod h1:DCzpHaOWr8IXmIStZouvnhqoel9Qv2LBy8hT2VhHyBg=
@@ -546,10 +534,8 @@ github.com/jsimonetti/rtnetlink v1.1.2-0.20220408201609-d380b505068b h1:Yws7RV6k
 github.com/jsimonetti/rtnetlink v1.1.2-0.20220408201609-d380b505068b/go.mod h1:TzDCVOZKUa79z6iXbbXqhtAflVgUKaFkZ21M5tK5tzY=
 github.com/json-iterator/go v1.1.6/go.mod h1:+SdeFBvtyEkXs7REEP0seUULqWtbJapLOCVDaaPEHmU=
 github.com/json-iterator/go v1.1.7/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
-github.com/json-iterator/go v1.1.9/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/json-iterator/go v1.1.10/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/json-iterator/go v1.1.11/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
-github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
 github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1:6v2b51hI/fHJwM22ozAgKL4VKDeJcHhJFhtBdhmNjmU=
 github.com/jstemmer/go-junit-report v0.9.1/go.mod h1:Brl9GWCQeLvo8nXZwPNNblvFj/XSXhF0NWZEnDohbsk=
@@ -595,8 +581,6 @@ github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+
 github.com/kyoh86/exportloopref v0.1.8/go.mod h1:1tUcJeiioIs7VWe5gcOObrux3lb66+sBqGZrRkMwPgg=
 github.com/ldez/gomoddirectives v0.2.2/go.mod h1:cpgBogWITnCfRq2qGoDkKMEVSaarhdBr6g8G04uz6d0=
 github.com/ldez/tagliatelle v0.2.0/go.mod h1:8s6WJQwEYHbKZDsp/LjArytKOG8qaMrKQQ3mFukHs88=
-github.com/leodido/go-urn v1.2.0 h1:hpXL4XnriNwQ/ABnpepYM/1vCLWNDfUNts8dX3xTG6Y=
-github.com/leodido/go-urn v1.2.0/go.mod h1:+8+nEpDfqqsY+g338gtMEUOtuK+4dEMhiQEgxpxOKII=
 github.com/letsencrypt/pkcs11key/v4 v4.0.0/go.mod h1:EFUvBDay26dErnNb70Nd0/VW3tJiIbETBPTl9ATXQag=
 github.com/lib/pq v0.0.0-20180327071824-d34b9ff171c2/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
 github.com/lib/pq v1.0.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
@@ -686,11 +670,9 @@ github.com/moby/sys/mountinfo v0.4.1/go.mod h1:rEr8tzG/lsIZHBtN/JjGG+LMYx9eXgW2J
 github.com/moby/term v0.0.0-20201216013528-df9cb8a40635 h1:rzf0wL0CHVc8CEsgyygG0Mn9CNCCPZqOPaz8RiiHYQk=
 github.com/moby/term v0.0.0-20201216013528-df9cb8a40635/go.mod h1:FBS0z0QWA44HXygs7VXDUOGoN/1TV3RuWkLO04am3wc=
 github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
-github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w8PVh93nsPXa1VrQ6jlwL5oN8l14QlcNfg=
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
 github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
-github.com/modern-go/reflect2 v1.0.2 h1:xBagoLtFs94CBntxluKeaWgTMpvLxC4ur3nMaC9Gz0M=
 github.com/modern-go/reflect2 v1.0.2/go.mod h1:yWuevngMOJpCy52FWWMvUC8ws7m/LJsjYzDa0/r8luk=
 github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826/go.mod h1:TaXosZuwdSHYgviHp1DAtfrULt5eUgsSMsZf+YrPgl8=
 github.com/moricho/tparallel v0.2.1/go.mod h1:fXEIZxG2vdfl0ZF8b42f5a78EhjjD5mX8qUplsoSU4k=
@@ -925,10 +907,7 @@ github.com/tmc/grpc-websocket-proxy v0.0.0-20200427203606-3cfed13b9966/go.mod h1
 github.com/tomarrell/wrapcheck/v2 v2.4.0/go.mod h1:68bQ/eJg55BROaRTbMjC7vuhL2OgfoG8bLp9ZyoBfyY=
 github.com/tomasen/realip v0.0.0-20180522021738-f0c99a92ddce/go.mod h1:o8v6yHRoik09Xen7gje4m9ERNah1d1PPsVq1VEx9vE4=
 github.com/tommy-muehle/go-mnd/v2 v2.4.0/go.mod h1:WsUAkMJMYww6l/ufffCD3m+P7LEvr8TnZn9lwVDlgzw=
-github.com/ugorji/go v1.1.7/go.mod h1:kZn38zHttfInRq0xu/PH0az30d+z6vm202qpg1oXVMw=
 github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8/go.mod h1:VFNgLljTbGfSG7qAOspJ7OScBnGdDN/yBr0sguwnwf0=
-github.com/ugorji/go/codec v1.1.7 h1:2SvQaVZ1ouYrrKKwoSk2pzd4A9evlKJb9oTL+OaLUSs=
-github.com/ugorji/go/codec v1.1.7/go.mod h1:Ax+UKWsSmolVDwsd+7N3ZtXu+yMGCf907BLYF3GoBXY=
 github.com/ultraware/funlen v0.0.3/go.mod h1:Dp4UiAus7Wdb9KUZsYWZEWiRzGuM2kXM1lPbfaF6xhA=
 github.com/ultraware/whitespace v0.0.4/go.mod h1:aVMh/gQve5Maj9hQ/hg+F75lr/X5A89uZnzAmWSineA=
 github.com/urfave/cli v1.20.0/go.mod h1:70zkFmudgCuE/ngEzBv17Jvp/497gISqfk5gWijbERA=
@@ -962,8 +941,6 @@ github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9dec
 github.com/yuin/goldmark v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 github.com/yuin/goldmark v1.4.0/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 github.com/zenazn/goji v0.9.0/go.mod h1:7S9M489iMyHBNxwZnk9/EHS098H4/F6TATF2mIxtB1Q=
-github.com/zsais/go-gin-prometheus v0.1.0 h1:bkLv1XCdzqVgQ36ScgRi09MA2UC1t3tAB6nsfErsGO4=
-github.com/zsais/go-gin-prometheus v0.1.0/go.mod h1:Slirjzuz8uM8Cw0jmPNqbneoqcUtY2GGjn2bEd4NRLY=
 go.etcd.io/bbolt v1.3.3/go.mod h1:IbVyRI1SCnLcuJnV2u8VeU0CEYM7e686BmAb1XKL+uU=
 go.etcd.io/bbolt v1.3.4/go.mod h1:G5EMThwa9y8QZGBClrRx5EY+Yw9kAhnjy3bSjsnlVTQ=
 go.etcd.io/etcd v0.0.0-20200513171258-e048e166ab9c/go.mod h1:xCI7ZzBfRuGgBXyXO6yfWfDmlWd35khcWpUa4L0xI/k=