oidc: Add /api/v1/config route for determining whether to display a login button on the UI

controller/handler/config.go

@@ -0,0 +1,26 @@
+package handler
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/TwiN/gatus/v3/security"
+)
+
+// ConfigHandler is a handler that returns information for the front end of the application.
+type ConfigHandler struct {
+	securityConfig *security.Config
+}
+
+func (handler ConfigHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	hasOIDC := false
+	isAuthenticated := false // Default to true if no security config is set
+	if handler.securityConfig != nil {
+		hasOIDC = handler.securityConfig.OIDC != nil
+		isAuthenticated = handler.securityConfig.IsAuthenticated(r)
+	}
+	// Return the config
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	_, _ = w.Write([]byte(fmt.Sprintf(`{"oidc":%v,"authenticated":%v}`, hasOIDC, isAuthenticated)))
+}

controller/handler/config_test.go

@@ -0,0 +1,34 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/TwiN/gatus/v3/security"
+	"github.com/gorilla/mux"
+)
+
+func TestConfigHandler_ServeHTTP(t *testing.T) {
+	securityConfig := &security.Config{
+		OIDC: &security.OIDCConfig{
+			IssuerURL:       "https://sso.gatus.io/",
+			RedirectURL:     "http://localhost:80/authorization-code/callback",
+			Scopes:          []string{"openid"},
+			AllowedSubjects: []string{"user1@example.com"},
+		},
+	}
+	handler := ConfigHandler{securityConfig: securityConfig}
+	// Create a fake router. We're doing this because I need the gate to be initialized.
+	securityConfig.ApplySecurityMiddleware(mux.NewRouter())
+	// Test the config handler
+	request, _ := http.NewRequest("GET", "/api/v1/config", http.NoBody)
+	responseRecorder := httptest.NewRecorder()
+	handler.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusOK {
+		t.Error("expected code to be 200, but was", responseRecorder.Code)
+	}
+	if responseRecorder.Body.String() != `{"oidc":true,"authenticated":false}` {
+		t.Error("expected body to be `{\"oidc\":true,\"authenticated\":false}`, but was", responseRecorder.Body.String())
+	}
+}

controller/handler/cors.go

@@ -4,7 +4,11 @@ import "net/http"
 
 func DevelopmentCORS(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Access-Control-Allow-Credentials", "true")
 		w.Header().Set("Access-Control-Allow-Origin", "http://localhost:8081")
+		if r.Method == "OPTIONS" {
+			return
+		}
 		next.ServeHTTP(w, r)
 	})
 }

controller/handler/handler.go

@@ -25,6 +25,7 @@ func CreateRouter(staticFolder string, securityConfig *security.Config, uiConfig
 		securityConfig.ApplySecurityMiddleware(protected)
 	}
 	// Endpoints
+	unprotected.Handle("/v1/config", ConfigHandler{securityConfig: securityConfig}).Methods("GET")
 	protected.HandleFunc("/v1/endpoints/statuses", EndpointStatuses).Methods("GET") // No GzipHandler for this one, because we cache the content as Gzipped already
 	protected.HandleFunc("/v1/endpoints/{key}/statuses", GzipHandlerFunc(EndpointStatus)).Methods("GET")
 	unprotected.HandleFunc("/v1/endpoints/{key}/uptimes/{duration}/badge.svg", UptimeBadge).Methods("GET")

go.mod

@@ -3,7 +3,7 @@ module github.com/TwiN/gatus/v3
 go 1.17
 
 require (
-	github.com/TwiN/g8 v1.2.0
+	github.com/TwiN/g8 v1.3.0
 	github.com/TwiN/gocache v1.2.4
 	github.com/TwiN/gocache/v2 v2.0.0
 	github.com/TwiN/health v1.3.0

go.sum

@@ -33,8 +33,8 @@ cloud.google.com/go/storage v1.10.0/go.mod h1:FLPqc6j+Ki4BU591ie1oL6qBQGu2Bl/tZ9
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
-github.com/TwiN/g8 v1.2.0 h1:pNCSaNuFe0B8cAm9Ir2aCsnAeO2j4Y1FsHeYop+mOXQ=
+github.com/TwiN/g8 v1.3.0 h1:mNv3R35GhDn1gEV0BKMl1oupZ1tDtOWPTHUKu+W/k3U=
-github.com/TwiN/g8 v1.2.0/go.mod h1:SiIdItS0agSUloFqdQQt/RObB2jGSq+nnE9WfFv3RIo=
+github.com/TwiN/g8 v1.3.0/go.mod h1:SiIdItS0agSUloFqdQQt/RObB2jGSq+nnE9WfFv3RIo=
 github.com/TwiN/gocache v1.2.4 h1:AfJ1YRcxtQ/zZEN61URDwk/dwFG7LSRenU5qIm9dQzo=
 github.com/TwiN/gocache v1.2.4/go.mod h1:BjabsQQy6z5uHDorHa4LJVPEzFeitLIDbCtdv3gc1gA=
 github.com/TwiN/gocache/v2 v2.0.0 h1:CPbDNKdSJpmBkh7aWcO7D3KK1yWaMlwX+3dsBPE8/so=

security/config.go

@@ -18,6 +18,8 @@ const (
 type Config struct {
 	Basic *BasicConfig `yaml:"basic,omitempty"`
 	OIDC  *OIDCConfig  `yaml:"oidc,omitempty"`
+
+	gate *g8.Gate
 }
 
 // IsValid returns whether the security configuration is valid or not
@@ -37,6 +39,8 @@ func (c *Config) RegisterHandlers(router *mux.Router) error {
 	return nil
 }
 
+// ApplySecurityMiddleware applies an authentication middleware to the router passed.
+// The router passed should be a subrouter in charge of handlers that require authentication.
 func (c *Config) ApplySecurityMiddleware(api *mux.Router) {
 	if c.OIDC != nil {
 		// We're going to use g8 for session handling
@@ -55,8 +59,8 @@ func (c *Config) ApplySecurityMiddleware(api *mux.Router) {
 		}
 		// TODO: g8: Add a way to update cookie after? would need the writer
 		authorizationService := g8.NewAuthorizationService().WithClientProvider(clientProvider)
-		gate := g8.New().WithAuthorizationService(authorizationService).WithCustomTokenExtractor(customTokenExtractorFunc)
+		c.gate = g8.New().WithAuthorizationService(authorizationService).WithCustomTokenExtractor(customTokenExtractorFunc)
-		api.Use(gate.Protect)
+		api.Use(c.gate.Protect)
 	} else if c.Basic != nil {
 		api.Use(func(handler http.Handler) http.Handler {
 			return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
@@ -72,3 +76,14 @@ func (c *Config) ApplySecurityMiddleware(api *mux.Router) {
 		})
 	}
 }
+
+// IsAuthenticated checks whether the user is authenticated
+// If the Config does not warrant authentication, it will always return true.
+func (c *Config) IsAuthenticated(r *http.Request) bool {
+	if c.gate != nil {
+		token := c.gate.ExtractTokenFromRequest(r)
+		_, hasSession := sessions.Get(token)
+		return hasSession
+	}
+	return false
+}

security/config_test.go

@@ -33,14 +33,14 @@ func TestConfig_ApplySecurityMiddleware(t *testing.T) {
 	})
 	c.ApplySecurityMiddleware(api)
 	// Try to access the route without basic auth
-	request, _ := http.NewRequest("GET", "/test", nil)
+	request, _ := http.NewRequest("GET", "/test", http.NoBody)
 	responseRecorder := httptest.NewRecorder()
 	api.ServeHTTP(responseRecorder, request)
 	if responseRecorder.Code != http.StatusUnauthorized {
 		t.Error("expected code to be 401, but was", responseRecorder.Code)
 	}
 	// Try again, but with basic auth
-	request, _ = http.NewRequest("GET", "/test", nil)
+	request, _ = http.NewRequest("GET", "/test", http.NoBody)
 	responseRecorder = httptest.NewRecorder()
 	request.SetBasicAuth("john.doe", "hunter2")
 	api.ServeHTTP(responseRecorder, request)
@@ -65,14 +65,14 @@ func TestConfig_ApplySecurityMiddleware(t *testing.T) {
 	c.Basic = nil
 	c.ApplySecurityMiddleware(api)
 	// Try without any session cookie
-	request, _ = http.NewRequest("GET", "/test", nil)
+	request, _ = http.NewRequest("GET", "/test", http.NoBody)
 	responseRecorder = httptest.NewRecorder()
 	api.ServeHTTP(responseRecorder, request)
 	if responseRecorder.Code != http.StatusUnauthorized {
 		t.Error("expected code to be 401, but was", responseRecorder.Code)
 	}
 	// Try with a session cookie
-	request, _ = http.NewRequest("GET", "/test", nil)
+	request, _ = http.NewRequest("GET", "/test", http.NoBody)
 	request.AddCookie(&http.Cookie{Name: "session", Value: "123"})
 	responseRecorder = httptest.NewRecorder()
 	api.ServeHTTP(responseRecorder, request)
@@ -86,7 +86,7 @@ func TestConfig_RegisterHandlers(t *testing.T) {
 	router := mux.NewRouter()
 	c.RegisterHandlers(router)
 	// Try to access the OIDC handler. This should fail, because the security config doesn't have OIDC
-	request, _ := http.NewRequest("GET", "/oidc/login", nil)
+	request, _ := http.NewRequest("GET", "/oidc/login", http.NoBody)
 	responseRecorder := httptest.NewRecorder()
 	router.ServeHTTP(responseRecorder, request)
 	if responseRecorder.Code != http.StatusNotFound {
@@ -107,7 +107,7 @@ func TestConfig_RegisterHandlers(t *testing.T) {
 	if err := c.RegisterHandlers(router); err != nil {
 		t.Fatal("expected no error, but got", err)
 	}
-	request, _ = http.NewRequest("GET", "/oidc/login", nil)
+	request, _ = http.NewRequest("GET", "/oidc/login", http.NoBody)
 	responseRecorder = httptest.NewRecorder()
 	router.ServeHTTP(responseRecorder, request)
 	if responseRecorder.Code != http.StatusFound {

vendor/github.com/TwiN/g8/gate.go

@@ -181,12 +181,7 @@ func (gate *Gate) ProtectFuncWithPermissions(handlerFunc http.HandlerFunc, permi
 			}
 		}
 		if gate.authorizationService != nil {
-			var token string
+			token := gate.ExtractTokenFromRequest(request)
-			if gate.customTokenExtractorFunc != nil {
-				token = gate.customTokenExtractorFunc(request)
-			} else {
-				token = extractTokenFromRequest(request)
-			}
 			if !gate.authorizationService.IsAuthorized(token, permissions) {
 				writer.WriteHeader(http.StatusUnauthorized)
 				_, _ = writer.Write(gate.unauthorizedResponseBody)
@@ -206,7 +201,17 @@ func (gate *Gate) ProtectFuncWithPermission(handlerFunc http.HandlerFunc, permis
 	return gate.ProtectFuncWithPermissions(handlerFunc, []string{permission})
 }
 
-// extractTokenFromRequest extracts the bearer token from the AuthorizationHeader
+// ExtractTokenFromRequest extracts a token from a request.
-func extractTokenFromRequest(request *http.Request) string {
+//
+// By default, it extracts the bearer token from the AuthorizationHeader, but if a customTokenExtractorFunc is defined,
+// it will use that instead.
+//
+// Note that this method is internally used by Protect, ProtectWithPermission, ProtectFunc and
+// ProtectFuncWithPermissions, but it is exposed in case you need to use it directly.
+func (gate *Gate) ExtractTokenFromRequest(request *http.Request) string {
+	if gate.customTokenExtractorFunc != nil {
+		// A custom token extractor function is defined, so we'll use it instead of the default token extraction logic
+		return gate.customTokenExtractorFunc(request)
+	}
 	return strings.TrimPrefix(request.Header.Get(AuthorizationHeader), "Bearer ")
 }

vendor/modules.txt

@@ -1,4 +1,4 @@
-# github.com/TwiN/g8 v1.2.0
+# github.com/TwiN/g8 v1.3.0
 ## explicit; go 1.17
 github.com/TwiN/g8
 # github.com/TwiN/gocache v1.2.4

web/app/src/App.vue

@@ -1,5 +1,5 @@
 <template>
-  <div class="container container-xs relative mx-auto xl:rounded xl:border xl:shadow-xl xl:my-5 p-5 pb-12 xl:pb-5 text-left dark:bg-gray-800 dark:text-gray-200 dark:border-gray-500" id="global">
+  <div v-if="retrievedConfig" class="container container-xs relative mx-auto xl:rounded xl:border xl:shadow-xl xl:my-5 p-5 pb-12 xl:pb-5 text-left dark:bg-gray-800 dark:text-gray-200 dark:border-gray-500" id="global">
     <div class="mb-2">
       <div class="flex flex-wrap">
         <div class="w-3/4 text-left my-auto">
@@ -11,6 +11,11 @@
         </div>
       </div>
     </div>
+    <div v-if="config && config.oidc && !config.authenticated">
+      <a :href="`${SERVER_URL}/oidc/login`" class="max-w-lg mx-auto w-full flex justify-center py-3 px-4 border border-transparent rounded-md shadow-lg text-white bg-green-700 hover:bg-green-800">
+        Login with OIDC
+      </a>
+    </div>
     <router-view @showTooltip="showTooltip"/>
   </div>
   <Tooltip :result="tooltip.result" :event="tooltip.event"/>
@@ -21,6 +26,7 @@
 <script>
 import Social from './components/Social.vue'
 import Tooltip from './components/Tooltip.vue';
+import {SERVER_URL} from "@/main";
 
 export default {
   name: 'App',
@@ -29,6 +35,17 @@ export default {
     Tooltip
   },
   methods: {
+    fetchConfig() {
+      fetch(`${SERVER_URL}/api/v1/config`, {credentials: 'include'})
+      .then(response => {
+        this.retrievedConfig = true;
+        if (response.status === 200) {
+          response.json().then(data => {
+            this.config = data;
+          })
+        }
+      });
+    },
     showTooltip(result, event) {
       this.tooltip = {result: result, event: event};
     }
@@ -40,8 +57,14 @@ export default {
   },
   data() {
     return {
-      tooltip: {}
+      retrievedConfig: false,
+      config: { oidc: false, authenticated: true },
+      tooltip: {},
+      SERVER_URL
     }
   },
+  created() {
+    this.fetchConfig();
+  }
 }
-</script>
+</script>

web/app/src/main.js

@@ -3,6 +3,6 @@ import App from './App.vue'
 import './index.css'
 import router from './router'
 
-export const SERVER_URL = process.env.NODE_ENV === 'production' ? '.' : 'http://localhost:8080'
+export const SERVER_URL = process.env.NODE_ENV === 'production' ? '' : 'http://localhost:8080'
 
 createApp(App).use(router).mount('#app')