fix OIDC not working when ISSUE_URL points to GoDoxy itself

cmd/main.go

@@ -127,11 +127,18 @@ func main() {
 		return
 	}
 
+	cfg.Start(&config.StartServersOptions{
+		Proxy:   true,
+		Metrics: true,
+	})
 	if err := auth.Initialize(); err != nil {
 		logging.Fatal().Err(err).Msg("failed to initialize authentication")
 	}
+	// API Handler needs to start after auth is initialized.
+	cfg.StartServers(&config.StartServersOptions{
+		API: true,
+	})
 
-	cfg.Start()
 	config.WatchChanges()
 
 	sig := make(chan os.Signal, 1)

internal/config/config.go

@@ -150,10 +150,10 @@ func (cfg *Config) Context() context.Context {
 	return cfg.task.Context()
 }
 
-func (cfg *Config) Start() {
+func (cfg *Config) Start(opts ...*StartServersOptions) {
 	cfg.StartAutoCert()
 	cfg.StartProxyProviders()
-	cfg.StartServers()
+	cfg.StartServers(opts...)
 }
 
 func (cfg *Config) StartAutoCert() {
@@ -187,7 +187,7 @@ type StartServersOptions struct {
 
 func (cfg *Config) StartServers(opts ...*StartServersOptions) {
 	if len(opts) == 0 {
-		opts = append(opts, &StartServersOptions{Proxy: true, API: true, Metrics: true})
+		opts = append(opts, &StartServersOptions{})
 	}
 	opt := opts[0]
 	if opt.Proxy {

internal/net/http/middleware/oidc.go

@@ -2,6 +2,8 @@ package middleware
 
 import (
 	"net/http"
+	"sync"
+	"sync/atomic"
 
 	"github.com/yusing/go-proxy/internal/api/v1/auth"
 	E "github.com/yusing/go-proxy/internal/error"
@@ -13,6 +15,9 @@ type oidcMiddleware struct {
 
 	auth    auth.Provider
 	authMux *http.ServeMux
+
+	isInitialized int32
+	initMu        sync.Mutex
 }
 
 var OIDC = NewMiddleware[oidcMiddleware]()
@@ -21,6 +26,29 @@ func (amw *oidcMiddleware) finalize() error {
 	if !auth.IsOIDCEnabled() {
 		return E.New("OIDC not enabled but OIDC middleware is used")
 	}
+	return nil
+}
+
+func (amw *oidcMiddleware) init() error {
+	if atomic.LoadInt32(&amw.isInitialized) == 1 {
+		return nil
+	}
+
+	return amw.initSlow()
+}
+
+func (amw *oidcMiddleware) initSlow() error {
+	amw.initMu.Lock()
+	if amw.isInitialized == 1 {
+		amw.initMu.Unlock()
+		return nil
+	}
+
+	defer func() {
+		amw.isInitialized = 1
+		amw.initMu.Unlock()
+	}()
+
 	authProvider, err := auth.NewOIDCProviderFromEnv()
 	if err != nil {
 		return err
@@ -45,6 +73,12 @@ func (amw *oidcMiddleware) finalize() error {
 }
 
 func (amw *oidcMiddleware) before(w http.ResponseWriter, r *http.Request) (proceed bool) {
+	if err := amw.init(); err != nil {
+		// no need to log here, main OIDC may already failed and logged
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return false
+	}
+
 	if err := amw.auth.CheckToken(r); err != nil {
 		amw.authMux.ServeHTTP(w, r)
 		return false