Problem with upgrading LiveView from 0.16 to 0.17/0.18

I’m running an old Phoenix LiveView app and today I wanted to upgrade from 0.16 to 0.17 (and eventually 0.18).

I have changed my mix.exs can ran mix deps.get and I can see the mix.lock being updated.

I have added import Phoenix.Component to PadelLisboaWeb.view_helpers

Changed all my .leex files to .heex and fixed all the errors/warnings when trying to build the app.

But somehow I have this strange issue that on initial loading, the page looks fine and it seems as soon as the WS connection is established, some content changes to “undefined”


I have a feeling it’s a tiny little thing that I’ve forgotten in the upgrade process. Has anyone else experienced this issue? (for the GIF I’m actively pressing CMD + R to refresh the page)

1 Like

what are you using to build js assets? If you have a node/npm setup, you will need to bust your npm deps and refetch. It looks like you are still on the old js client.


Yes, you are right… Banging my head against the wall now… Thank you very much. :pray:

For anyone else coming across the same issue, don’t forget to update your js packages in assets/package.json

-    "phoenix": "1.6.0-rc.0",
-    "phoenix_html": "2.14.3",
-    "phoenix_live_view": "0.16.3",
+    "phoenix": "1.6.15",
+    "phoenix_html": "3.2.0",
+    "phoenix_live_view": "0.18.2"