Checking authentication on the backend

cmd/api/handlers-api.go

@@ -297,3 +297,7 @@ func (app *application) CreateAuthToken(w http.ResponseWriter, r *http.Request)
 
 	_ = app.writeJSON(w, http.StatusOK, payload)
 }
+
+func (app *application) CheckAuthentication(w http.ResponseWriter, r *http.Request) {
+	app.invalidCredentials(w)
+}

cmd/api/routes-api.go

@@ -23,6 +23,7 @@ func (app *application) routes() http.Handler {
 	mux.Post("/api/create-customer-and-subscribe-to-plan", app.CreateCustomerAndSubscribeToPlan)
 
 	mux.Post("/api/authenticate", app.CreateAuthToken)
+	mux.Post("/api/is-authenticated", app.CheckAuthentication)
 
 	return mux
 }

cmd/web/templates/terminal.page.gohtml

@@ -76,8 +76,10 @@ Virtual Terminal
 {{ define "js" }}
 <script src="https://js.stripe.com/v3/"></script>
 <script type="module">
-    import {stripeInit} from "/static/js/common.js";
+    import {stripeInit, checkAuth} from "/static/js/common.js";
     import {val} from "/static/js/stripe.js"
+
+    checkAuth({{.API}});
     stripeInit('{{.StripePubKey}}');
     document.getElementById("charge_amount").addEventListener("change", (evt) => {
         if (evt.target.value !== "") {