From 38ce40ae7df5148f3e56a461c1235e4a8371023c Mon Sep 17 00:00:00 2001
From: Christoph Kluge <christoph.kluge@fau.de>
Date: Tue, 26 Nov 2024 16:21:16 +0100
Subject: [PATCH] feat: redirect to requested page after login, solves #281

---
 cmd/cc-backend/server.go                      | 19 ++++++++-----------
 internal/auth/auth.go                         |  8 ++++++--
 .../taskManager/updateFootprintService.go     |  4 ++--
 web/templates/login.tmpl                      |  1 +
 web/web.go                                    |  1 +
 5 files changed, 18 insertions(+), 15 deletions(-)

diff --git a/cmd/cc-backend/server.go b/cmd/cc-backend/server.go
index fc620c8..083b9e5 100644
--- a/cmd/cc-backend/server.go
+++ b/cmd/cc-backend/server.go
@@ -110,9 +110,7 @@ func serverInit() {
 
 	if !config.Keys.DisableAuthentication {
 		router.Handle("/login", authHandle.Login(
-			// On success:
-			http.RedirectHandler("/", http.StatusTemporaryRedirect),
-
+			// On success: Handled within Login()
 			// On failure:
 			func(rw http.ResponseWriter, r *http.Request, err error) {
 				rw.Header().Add("Content-Type", "text/html; charset=utf-8")
@@ -127,9 +125,7 @@ func serverInit() {
 			})).Methods(http.MethodPost)
 
 		router.Handle("/jwt-login", authHandle.Login(
-			// On success:
-			http.RedirectHandler("/", http.StatusTemporaryRedirect),
-
+			// On success: Handled within Login()
 			// On failure:
 			func(rw http.ResponseWriter, r *http.Request, err error) {
 				rw.Header().Add("Content-Type", "text/html; charset=utf-8")
@@ -165,11 +161,12 @@ func serverInit() {
 				func(rw http.ResponseWriter, r *http.Request, err error) {
 					rw.WriteHeader(http.StatusUnauthorized)
 					web.RenderTemplate(rw, "login.tmpl", &web.Page{
-						Title:   "Authentication failed - ClusterCockpit",
-						MsgType: "alert-danger",
-						Message: err.Error(),
-						Build:   buildInfo,
-						Infos:   info,
+						Title:    "Authentication failed - ClusterCockpit",
+						MsgType:  "alert-danger",
+						Message:  err.Error(),
+						Build:    buildInfo,
+						Infos:    info,
+						Redirect: r.RequestURI,
 					})
 				})
 		})
diff --git a/internal/auth/auth.go b/internal/auth/auth.go
index 270989f..a186cf6 100644
--- a/internal/auth/auth.go
+++ b/internal/auth/auth.go
@@ -201,7 +201,6 @@ func (auth *Authentication) SaveSession(rw http.ResponseWriter, r *http.Request,
 }
 
 func (auth *Authentication) Login(
-	onsuccess http.Handler,
 	onfailure func(rw http.ResponseWriter, r *http.Request, loginErr error),
 ) http.Handler {
 	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
@@ -238,7 +237,12 @@ func (auth *Authentication) Login(
 
 			log.Infof("login successfull: user: %#v (roles: %v, projects: %v)", user.Username, user.Roles, user.Projects)
 			ctx := context.WithValue(r.Context(), repository.ContextUserKey, user)
-			onsuccess.ServeHTTP(rw, r.WithContext(ctx))
+
+			if r.FormValue("redirect") != "" {
+				http.RedirectHandler(r.FormValue("redirect"), http.StatusFound).ServeHTTP(rw, r.WithContext(ctx))
+			} else {
+				http.RedirectHandler(r.FormValue("/"), http.StatusFound).ServeHTTP(rw, r.WithContext(ctx))
+			}
 			return
 		}
 
diff --git a/internal/taskManager/updateFootprintService.go b/internal/taskManager/updateFootprintService.go
index e9525d2..d30d766 100644
--- a/internal/taskManager/updateFootprintService.go
+++ b/internal/taskManager/updateFootprintService.go
@@ -43,9 +43,9 @@ func RegisterFootprintWorker() {
 					if err != nil {
 						continue
 					}
-					// NOTE: Additional Subcluster Loop Could Allow For Limited List Of (Energy)Footprint-Metrics Only.
+					// NOTE: Additional Subcluster Loop Could Allow For Limited List Of Footprint-Metrics Only.
 					//       - Chunk-Size Would Then Be 'SubCluster' (Running Jobs, Transactions) as Lists Can Change Within SCs
-					//       - Would Require Review of 'updateFootprint' And 'updateEnergy' Usage
+					//       - Would Require Review of 'updateFootprint' Usage (Logic Could Possibly Be Included Here Completely)
 					allMetrics := make([]string, 0)
 					metricConfigs := archive.GetCluster(cluster.Name).MetricConfig
 					for _, mc := range metricConfigs {
diff --git a/web/templates/login.tmpl b/web/templates/login.tmpl
index f10e064..cd13926 100644
--- a/web/templates/login.tmpl
+++ b/web/templates/login.tmpl
@@ -41,6 +41,7 @@
                                 {{- if .Infos.hasOpenIDConnect}}
                                 <a class="btn btn-primary" href="/oidc-login">OpenID Connect Login</a>
                                 {{end}}
+                                <input type="hidden" id="redirect" name="redirect" value="{{ .Redirect }}" />
                             </form>
                         </div>
                     </div>
diff --git a/web/web.go b/web/web.go
index 45ca9e3..1cfa176 100644
--- a/web/web.go
+++ b/web/web.go
@@ -99,6 +99,7 @@ type Page struct {
 	Infos         map[string]interface{} // For generic use (e.g. username for /monitoring/user/<id>, job id for /monitoring/job/<id>)
 	Config        map[string]interface{} // UI settings for the currently logged in user (e.g. line width, ...)
 	Resampling    *schema.ResampleConfig // If not nil, defines resampling trigger and resolutions
+	Redirect      string                 // The originally requested URL, for intermediate login handling
 }
 
 func RenderTemplate(rw http.ResponseWriter, file string, page *Page) {