chore: short docs on middleware

handlers.go

@@ -128,6 +128,15 @@ func logoutHandler(c *gin.Context) {
 	session := sessions.Default(c)
 	session.Clear()
 	session.Save()
+	redir := ""
+	if c.Query("returnTo") != "" {
+		redir = c.Query("returnTo")
+	}
+	if redir != "" {
+		c.Redirect(307, redir)
+	} else {
+		c.Redirect(307, defaultRedirect)
+	}
 }
 
 // Ensure that a user is currently logged in.

main.go

@@ -20,18 +20,30 @@ func createRandomString(n int) (string, error) {
 	return base64.URLEncoding.EncodeToString(s), nil
 }
 
+type UserFunc func(userid string, name string, email string)
+
 var (
 	config          oauth2.Config
-	userFunc        func(userid string, name string, email string)
+	userFunc        UserFunc
 	verifier        oidc.IDTokenVerifier
 	defaultRedirect string
 )
 
-// Configure and set up the login SDK.
-func Configure(r *gin.Engine, app_url string, default_redirect string, stubs_on_unconfigured bool) {
+// Wraps the normal configure function, but also gives you access to change the User Function, which is called upon login.
+// It is used to create or update a user.
+// The check middleware may be nil, in which case a default is used. Otherwise should be a valid gin middleware, calling c.Next() if okay to proceed.
+func ConfigureFull(r *gin.Engine, app_url string, default_redirect string, user_function UserFunc, stubs_on_unconfigured bool, check_middleware *func(c *gin.Context)) {
+	userFunc = user_function
+	Configure(r, app_url, default_redirect, stubs_on_unconfigured, check_middleware)
+}
+
+// Configure and set up the login SDK
+// The check middleware may be nil, in which case a default is used. Otherwise should be a valid gin middleware, calling c.Next() if okay to proceed.
+func Configure(r *gin.Engine, app_url string, default_redirect string, stubs_on_unconfigured bool, check_middleware *func(c *gin.Context)) {
 	issuer := os.Getenv("OIDC_ISSUER")
 	clientID := os.Getenv("OIDC_CLIENT_ID")
 	clientSecret := os.Getenv("OIDC_CLIENT_SECRET")
+	defaultRedirect = default_redirect
 
 	if issuer == "" || clientID == "" || clientSecret == "" {
 		if stubs_on_unconfigured {
@@ -45,7 +57,6 @@ func Configure(r *gin.Engine, app_url string, default_redirect string, stubs_on_
 
 	provider, err := oidc.NewProvider(context.Background(), issuer)
 	verifier = *provider.Verifier(&oidc.Config{ClientID: clientID})
-	defaultRedirect = default_redirect
 
 	if err != nil {
 		log.Fatal("[JHID] Provider resolution failed with error", err)
@@ -61,7 +72,12 @@ func Configure(r *gin.Engine, app_url string, default_redirect string, stubs_on_
 
 	r.GET("/auth/v2/login", loginHandler)
 	r.GET("/auth/v2/verify", callbackHandler)
-	r.GET("/auth/v2/check", EnsureLogin(false), func(ctx *gin.Context) { ctx.JSON(200, gin.H{"success": "true"}) })
+	check_finalizer := func(ctx *gin.Context) { ctx.JSON(200, gin.H{"success": "true"}) }
+	if check_middleware == nil {
+		r.GET("/auth/v2/check", EnsureLogin(false), check_finalizer)
+	} else {
+		r.GET("/auth/v2/check", EnsureLogin(false), *check_middleware, check_finalizer)
+	}
 	r.GET("/auth/v2/logout", logoutHandler)
 
 	log.Println("[JHID] Configured successfully")