Do not ask for explicit confirmation on logout

Fixes issue #8.

server/bindata.go

@@ -1247,7 +1247,6 @@ func templatesLogin_u2fHtml() (*asset, error) {
 
 var _templatesLogoutHtml = []byte(`{{template "header" .}}
 
-{{if .IsPOST}}
     <div class="form-signin">
       <h1 class="form-signin-heading>">Sign Out</h1>
 
@@ -1287,26 +1286,6 @@ var _templatesLogoutHtml = []byte(`{{template "header" .}}
       <div id="services" data-services="{{.ServicesJSON}}"></div>
 
     </div>
-{{else}}
-    <form class="form-signin" action="{{.URLPrefix}}/logout" method="post">
-      {{.CSRFField}}
-
-      <h1 class="form-signin-heading">Sign Out</h1>
-
-      <p>
-        You are about to sign out from the following services:
-      </p>
-
-      <ul>
-        {{range .Services}}
-        <li>{{.Name}}</li>
-        {{end}}
-      </ul>
-
-      <button type="submit" class="btn btn-lg btn-primary btn-block">Logout</button>
-
-    </form>
-{{end}}
 
 {{template "footer" .}}
 `)
@@ -1321,7 +1300,7 @@ func templatesLogoutHtml() (*asset, error) {
 		return nil, err
 	}
 
-	info := bindataFileInfo{name: "templates/logout.html", size: 1524, mode: os.FileMode(420), modTime: time.Unix(1541234913, 0)}
+	info := bindataFileInfo{name: "templates/logout.html", size: 1063, mode: os.FileMode(420), modTime: time.Unix(1548600535, 0)}
 	a := &asset{bytes: bytes, info: info}
 	return a, nil
 }

server/http.go

@@ -299,37 +299,34 @@ func (h *Server) handleLogout(w http.ResponseWriter, req *http.Request, session
 		})
 	}
 
+	svcJSON, _ := json.Marshal(svcs) // nolint
 	data := map[string]interface{}{
-		"CSRFField": csrf.TemplateField(req),
-		"URLPrefix": h.urlPrefix,
-		"Services":  svcs,
-		"IsPOST":    false,
+		"CSRFField":            csrf.TemplateField(req),
+		"URLPrefix":            h.urlPrefix,
+		"Services":             svcs,
+		"IncludeLogoutScripts": true,
+		"ServicesJSON":         string(svcJSON),
 	}
-	if req.Method == "POST" {
-		data["IsPOST"] = true
-		data["IncludeLogoutScripts"] = true
-		svcJSON, _ := json.Marshal(svcs) // nolint
-		data["ServicesJSON"] = string(svcJSON)
-
-		// Clear the local session. Ignore errors.
-		httpSession, _ := h.authSessionStore.Get(req, authSessionKey) // nolint
-		httpSession.Options.MaxAge = -1
-		httpSession.Save(req, w) // nolint
 
-		// Close the keystore.
-		if h.keystore != nil {
-			var shard string
-			if session.UserInfo != nil {
-				shard = session.UserInfo.Shard
-			}
-			if err := h.keystore.Close(req.Context(), shard, session.Username); err != nil {
-				log.Printf("failed to wipe keystore for user %s: %v", session.Username, err)
-			}
+	// Clear the local session. Ignore errors.
+	httpSession, _ := h.authSessionStore.Get(req, authSessionKey) // nolint
+	delete(httpSession.Values, "data")
+	httpSession.Options.MaxAge = -1
+	httpSession.Save(req, w) // nolint
+
+	// Close the keystore.
+	if h.keystore != nil {
+		var shard string
+		if session.UserInfo != nil {
+			shard = session.UserInfo.Shard
+		}
+		if err := h.keystore.Close(req.Context(), shard, session.Username); err != nil {
+			log.Printf("failed to wipe keystore for user %s: %v", session.Username, err)
 		}
-
-		w.Header().Set("Content-Security-Policy", logoutContentSecurityPolicy)
 	}
 
+	w.Header().Set("Content-Security-Policy", logoutContentSecurityPolicy)
+
 	h.tpl.ExecuteTemplate(w, "logout.html", data) // nolint
 }
 

server/templates/logout.html

 {{template "header" .}}
 
-{{if .IsPOST}}
     <div class="form-signin">
       <h1 class="form-signin-heading>">Sign Out</h1>
 
@@ -40,25 +39,5 @@
       <div id="services" data-services="{{.ServicesJSON}}"></div>
 
     </div>
-{{else}}
-    <form class="form-signin" action="{{.URLPrefix}}/logout" method="post">
-      {{.CSRFField}}
-
-      <h1 class="form-signin-heading">Sign Out</h1>
-
-      <p>
-        You are about to sign out from the following services:
-      </p>
-
-      <ul>
-        {{range .Services}}
-        <li>{{.Name}}</li>
-        {{end}}
-      </ul>
-
-      <button type="submit" class="btn btn-lg btn-primary btn-block">Logout</button>
-
-    </form>
-{{end}}
 
 {{template "footer" .}}