Fix APP-46E: accept invitation 2nd click (#3120)

* Fix APP-46E: accept invitation 2nd click

* :LspStop

* Update lib/plausible_web/controllers/invitation_controller.ex

Co-authored-by: Vini Brasil <vini@hey.com>

---------

Co-authored-by: Vini Brasil <vini@hey.com>

lib/plausible_web/controllers/invitation_controller.ex

@@ -14,9 +14,10 @@ defmodule PlausibleWeb.InvitationController do
 
   def accept_invitation(conn, %{"invitation_id" => invitation_id}) do
     invitation =
-      Repo.get_by!(Invitation, invitation_id: invitation_id)
+      Repo.get_by(Invitation, invitation_id: invitation_id)
       |> Repo.preload([:site, :inviter])
 
+    if invitation do
       user = conn.assigns[:current_user]
       existing_membership = Repo.get_by(Membership, user_id: user.id, site_id: invitation.site.id)
 
@@ -49,11 +50,16 @@ defmodule PlausibleWeb.InvitationController do
           |> put_flash(:success, "You now have access to #{invitation.site.domain}")
           |> redirect(to: "/#{URI.encode_www_form(invitation.site.domain)}")
 
-      {:error, _, _} ->
+        {:error, _operation, _value, _changes} ->
           conn
           |> put_flash(:error, "Something went wrong, please try again")
           |> redirect(to: "/sites")
       end
+    else
+      conn
+      |> put_flash(:error, "Invitation missing or already accepted")
+      |> redirect(to: "/sites")
+    end
   end
 
   defp downgrade_previous_owner(multi, site) do

test/plausible_web/controllers/invitation_controller_test.exs

@@ -17,7 +17,12 @@ defmodule PlausibleWeb.Site.InvitationControllerTest do
           role: :admin
         )
 
-      post(conn, "/sites/invitations/#{invitation.invitation_id}/accept")
+      conn = post(conn, "/sites/invitations/#{invitation.invitation_id}/accept")
+
+      assert Phoenix.Flash.get(conn.assigns.flash, :success) ==
+               "You now have access to #{site.domain}"
+
+      assert redirected_to(conn) == "/#{site.domain}"
 
       refute Repo.exists?(from(i in Plausible.Auth.Invitation, where: i.email == ^user.email))
 
@@ -25,6 +30,30 @@ defmodule PlausibleWeb.Site.InvitationControllerTest do
       assert membership.role == :admin
     end
 
+    test "does not crash if clicked for the 2nd time in another tab", %{conn: conn, user: user} do
+      site = insert(:site)
+
+      invitation =
+        insert(:invitation,
+          site_id: site.id,
+          inviter: build(:user),
+          email: user.email,
+          role: :admin
+        )
+
+      c1 = post(conn, "/sites/invitations/#{invitation.invitation_id}/accept")
+      assert redirected_to(c1) == "/#{site.domain}"
+
+      assert Phoenix.Flash.get(c1.assigns.flash, :success) ==
+               "You now have access to #{site.domain}"
+
+      c2 = post(conn, "/sites/invitations/#{invitation.invitation_id}/accept")
+      assert redirected_to(c2) == "/sites"
+
+      assert Phoenix.Flash.get(c2.assigns.flash, :error) ==
+               "Invitation missing or already accepted"
+    end
+
     test "notifies the original inviter", %{conn: conn, user: user} do
       inviter = insert(:user)
       site = insert(:site)