Replace logrus with slog (#3)

cmd/gangway/handlers.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	htmltemplate "html/template"
 	"io"
+	"log/slog"
 	"net/http"
 	"net/url"
 	"os"
@@ -31,7 +32,6 @@ import (
 	"github.com/golang-jwt/jwt/v5"
 	"github.com/heptiolabs/gangway/internal/oidc"
 	"github.com/heptiolabs/gangway/templates"
-	log "github.com/sirupsen/logrus"
 	"golang.org/x/oauth2"
 	clientcmdapi "k8s.io/client-go/tools/clientcmd/api/v1"
 )
@@ -69,14 +69,14 @@ func serveTemplate(tmplFile string, data interface{}, w http.ResponseWriter) {
 		templatePath := filepath.Join(cfg.CustomHTMLTemplatesDir, tmplFile)
 		templateData, err := os.ReadFile(templatePath)
 		if err != nil {
-			log.Errorf("Failed to find template asset: %s at path: %s", tmplFile, templatePath)
+			slog.Error("Failed to find template asset", "asset", tmplFile, "path", templatePath)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
 
 		tmpl, err = tmpl.Parse(string(templateData))
 		if err != nil {
-			log.Errorf("Failed to parse template: %v", err)
+			slog.Error("Failed to parse template", "error", err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
@@ -85,7 +85,7 @@ func serveTemplate(tmplFile string, data interface{}, w http.ResponseWriter) {
 
 		tmpl, err = tmpl.ParseFS(templates.FS, tmplFile)
 		if err != nil {
-			log.Errorf("Failed to parse template: %v", err)
+			slog.Error("Failed to parse template", "error", err)
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 		}
 	}
@@ -171,7 +171,7 @@ func loginHandler(w http.ResponseWriter, r *http.Request) {
 
 	session, err := gangwayUserSession.Session.Get(r, "gangway")
 	if err != nil {
-		log.Errorf("Got an error in login: %s", err)
+		slog.Error("Got an error in login", "error", err)
 		http.Error(w, err.Error(), http.StatusInternalServerError)
 		return
 	}
@@ -278,7 +278,7 @@ func kubeConfigHandler(w http.ResponseWriter, r *http.Request) {
 
 	d, err := yaml.Marshal(generateKubeConfig(info))
 	if err != nil {
-		log.Errorf("Error creating kubeconfig - %s", err.Error())
+		slog.Error("Error creating kubeconfig", "error", err.Error())
 		http.Error(w, "Error creating kubeconfig", http.StatusInternalServerError)
 		return
 	}
@@ -294,12 +294,12 @@ func generateInfo(w http.ResponseWriter, r *http.Request) *userInfo {
 	if err != nil {
 		// let us know that we couldn't open the file. This only cause missing output
 		// does not impact actual function of program
-		log.Errorf("Failed to open CA file. %s", err)
+		slog.Error("Failed to open CA file", "error", err)
 	}
 	defer file.Close()
 	caBytes, err := io.ReadAll(file)
 	if err != nil {
-		log.Warningf("Could not read CA file: %s", err)
+		slog.Warn("Could not read CA file", "error", err)
 	}
 
 	// load the session cookies
@@ -350,7 +350,7 @@ func generateInfo(w http.ResponseWriter, r *http.Request) *userInfo {
 	kubeCfgUser := strings.Join([]string{username, cfg.ClusterName}, "@")
 
 	if cfg.EmailClaim != "" {
-		log.Warn("using the Email Claim config setting is deprecated. Gangway uses `UsernameClaim@ClusterName`. This field will be removed in a future version.")
+		slog.Warn("Using the Email Claim config setting is deprecated. Gangway uses `UsernameClaim@ClusterName`. This field will be removed in a future version.")
 	}
 
 	issuerURL, ok := claims["iss"].(string)
@@ -360,7 +360,7 @@ func generateInfo(w http.ResponseWriter, r *http.Request) *userInfo {
 	}
 
 	if cfg.ClientSecret == "" {
-		log.Warn("Setting an empty Client Secret should only be done if you have no other option and is an inherent security risk.")
+		slog.Warn("Setting an empty Client Secret should only be done if you have no other option and is an inherent security risk.")
 	}
 
 	info := &userInfo{

cmd/gangway/main.go

@@ -19,6 +19,7 @@ import (
 	"crypto/tls"
 	"flag"
 	"fmt"
+	"log/slog"
 	"net/http"
 	"os"
 	"os/signal"
@@ -29,7 +30,6 @@ import (
 	"github.com/heptiolabs/gangway/internal/oidc"
 	"github.com/heptiolabs/gangway/internal/session"
 	"github.com/justinas/alice"
-	log "github.com/sirupsen/logrus"
 	"golang.org/x/oauth2"
 )
 
@@ -42,19 +42,30 @@ var transportConfig *config.TransportConfig
 // wrapper function for http logging
 func httpLogger(fn http.HandlerFunc) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
-		defer log.Printf("%s %s %s", r.Method, r.URL, r.RemoteAddr)
+		defer slog.Debug("HTTP log", "method", r.Method, "url", r.URL, "remote-addr", r.RemoteAddr)
 		fn(w, r)
 	}
 }
 
 func main() {
 	cfgFile := flag.String("config", "", "The config file to use.")
+	logLevel := flag.String("log-level", "info", "The log level to use. (debug, info, warn, error)")
 	flag.Parse()
 
+	var logLevelVar = new(slog.LevelVar)
+
+	h := slog.NewTextHandler(os.Stderr, &slog.HandlerOptions{Level: logLevelVar})
+	slog.SetDefault(slog.New(h))
+
+	if err := logLevelVar.UnmarshalText([]byte(*logLevel)); err != nil {
+		slog.Error("Could not parse log level", "error", err)
+		os.Exit(1)
+	}
+
 	var err error
 	cfg, err = config.NewConfig(*cfgFile)
 	if err != nil {
-		log.Errorf("Could not parse config file: %s", err)
+		slog.Error("Could not parse config file", "error", err)
 		os.Exit(1)
 	}
 
@@ -115,14 +126,20 @@ func main() {
 
 	// start up the http server
 	go func() {
-		log.Infof("Gangway started! Listening on: %s", bindAddr)
+		slog.Info("Gangway started", "address", bindAddr)
 
 		// exit with FATAL logging why we could not start
 		// example: FATA[0000] listen tcp 0.0.0.0:8080: bind: address already in use
 		if cfg.ServeTLS {
-			log.Fatal(httpServer.ListenAndServeTLS(cfg.CertFile, cfg.KeyFile))
+			if err := httpServer.ListenAndServeTLS(cfg.CertFile, cfg.KeyFile); err != nil {
+				slog.Error("Could not start HTTPS server", "error", err)
+				os.Exit(1)
+			}
 		} else {
-			log.Fatal(httpServer.ListenAndServe())
+			if err := httpServer.ListenAndServe(); err != nil {
+				slog.Error("Could not start HTTP server", "error", err)
+				os.Exit(1)
+			}
 		}
 	}()
 
@@ -131,7 +148,7 @@ func main() {
 	signal.Notify(signalChan, syscall.SIGINT, syscall.SIGTERM)
 	<-signalChan
 
-	log.Println("Shutdown signal received, exiting.")
+	slog.Info("Shutdown signal received, exiting")
 	// close the HTTP server
 	httpServer.Shutdown(context.Background())
 }

go.mod

@@ -9,7 +9,6 @@ require (
 	github.com/gorilla/sessions v1.2.2
 	github.com/justinas/alice v1.2.0
 	github.com/kelseyhightower/envconfig v1.4.0
-	github.com/sirupsen/logrus v1.9.3
 	golang.org/x/crypto v0.20.0
 	golang.org/x/oauth2 v0.17.0
 	gopkg.in/yaml.v2 v2.4.0
@@ -24,7 +23,6 @@ require (
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	golang.org/x/net v0.21.0 // indirect
-	golang.org/x/sys v0.17.0 // indirect
 	google.golang.org/appengine v1.6.7 // indirect
 	google.golang.org/protobuf v1.31.0 // indirect
 	k8s.io/apimachinery v0.29.2 // indirect

go.sum

@@ -57,11 +57,8 @@ github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/sirupsen/logrus v1.9.3 h1:dueUQJ1C2q9oE3F7wvmSGAaVtTmUizReu6fjN8uqzbQ=
-github.com/sirupsen/logrus v1.9.3/go.mod h1:naHLuLoDiP4jHNo9R0sCBMtWGeIprob74mVsIT4qYEQ=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
-github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
@@ -88,9 +85,6 @@ golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.17.0 h1:25cE3gD+tdBA7lp7QfhuV+rJiE9YXTcS3VG1SqssI/Y=
-golang.org/x/sys v0.17.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
@@ -117,7 +111,6 @@ gopkg.in/inf.v0 v0.9.1/go.mod h1:cWUDdTG/fYaXco+Dcufb5Vnc6Gp2YChqWtbxRZE0mXw=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 k8s.io/apimachinery v0.29.2 h1:EWGpfJ856oj11C52NRCHuU7rFDwxev48z+6DSlGNsV8=

internal/config/transport.go

@@ -16,7 +16,7 @@ package config
 import (
 	"crypto/tls"
 	"crypto/x509"
-	"log"
+	"log/slog"
 	"net"
 	"net/http"
 	"os"
@@ -39,12 +39,13 @@ func NewTransportConfig(trustedCAPath string) *TransportConfig {
 		// Read in the cert file
 		certs, err := os.ReadFile(trustedCAPath)
 		if err != nil {
-			log.Fatalf("Failed to append %q to RootCAs: %v", trustedCAPath, err)
+			slog.Error("Failed to append CA to RootCAs", "ca", trustedCAPath, "error", err)
+			os.Exit(1)
 		}
 
 		// Append our cert to the system pool
 		if ok := rootCAs.AppendCertsFromPEM(certs); !ok {
-			log.Println("No certs appended, using system certs only")
+			slog.Info("No certs appended, using system certs only")
 		}
 	}
 

internal/oidc/token_test.go

@@ -16,7 +16,6 @@ package oidc
 import (
 	"bytes"
 	"encoding/base64"
-	"log"
 	"testing"
 
 	"github.com/golang-jwt/jwt/v5"
@@ -26,7 +25,7 @@ func TestParseToken(t *testing.T) {
 	base64Decode := func(src string) []byte {
 		data, err := base64.RawURLEncoding.DecodeString(src)
 		if err != nil {
-			log.Fatal("error:", err)
+			t.Fatalf("Error decoding base64 string: %v", err)
 		}
 
 		return data

internal/session/session_test.go

@@ -20,7 +20,6 @@ import (
 	"testing"
 
 	"github.com/gorilla/sessions"
-	log "github.com/sirupsen/logrus"
 )
 
 func TestGenerateSessionKeys(t *testing.T) {
@@ -53,7 +52,7 @@ func TestCleanupSession(t *testing.T) {
 	defer ts.Close()
 	_, err := http.Get(ts.URL)
 	if err != nil {
-		log.Fatal(err)
+		t.Fatalf("Error getting from test server: %v", err)
 	}
 	if session.Options.MaxAge != -1 {
 		t.Errorf("Session was not reset. Have max age of %d. Should have -1", session.Options.MaxAge)

internal/session/store_test.go

@@ -15,21 +15,21 @@ package session
 
 import (
 	"fmt"
-	"github.com/gorilla/sessions"
-	log "github.com/sirupsen/logrus"
 	"math"
 	"math/rand"
 	"net/http"
 	"net/http/httptest"
 	"strings"
 	"testing"
+
+	"github.com/gorilla/sessions"
 )
 
 func TestJoinSectionCookies(t *testing.T) {
 	var originalValue string
 	var value string
 	cookies := buildRandomCookies(2, 3800, "test_%d")
-	buildRequestWithCookies(cookies, func(cookies []*http.Cookie, r *http.Request) {
+	buildRequestWithCookies(t, cookies, func(cookies []*http.Cookie, r *http.Request) {
 		for _, c := range cookies {
 			originalValue += c.Value
 		}
@@ -44,7 +44,7 @@ func TestJoinSectionCookiesSingle(t *testing.T) {
 	var originalValue string
 	var value string
 	cookies := buildRandomCookies(1, 2000, "test_%d")
-	buildRequestWithCookies(cookies, func(cookies []*http.Cookie, r *http.Request) {
+	buildRequestWithCookies(t, cookies, func(cookies []*http.Cookie, r *http.Request) {
 		for _, c := range cookies {
 			originalValue += c.Value
 		}
@@ -96,7 +96,7 @@ func TestSplitAndJoin(t *testing.T) {
 	sectionCookies := splitCookie(originalValue)
 	cookies := buildCookiesFromValues(sectionCookies, "test_%d")
 	var value string
-	buildRequestWithCookies(cookies, func(cookies []*http.Cookie, r *http.Request) {
+	buildRequestWithCookies(t, cookies, func(cookies []*http.Cookie, r *http.Request) {
 		value = joinSectionCookies(r, "test")
 	})
 	if value != originalValue {
@@ -108,7 +108,7 @@ func TestSplitAndJoin(t *testing.T) {
 
 type handleReq func([]*http.Cookie, *http.Request)
 
-func buildRequestWithCookies(cookies []*http.Cookie, fn handleReq) {
+func buildRequestWithCookies(t *testing.T, cookies []*http.Cookie, fn handleReq) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		for _, cookie := range cookies {
 			r.AddCookie(cookie)
@@ -118,7 +118,7 @@ func buildRequestWithCookies(cookies []*http.Cookie, fn handleReq) {
 	defer ts.Close()
 	_, err := http.Get(ts.URL)
 	if err != nil {
-		log.Fatal(err)
+		t.Fatalf("Error getting from test server: %v", err)
 	}
 }