Trying to replace entire collection with stream_insert not working

Phoenix Forum Questions / Help
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1

Hello! I’m having an issue getting stream_insert to replace the entire collection. Inside a handle_event/3 function, I’m doing:
{:noreply, stream_insert(socket, :projects, projects, reset: true)}

However, I’m getting an error:

** (ArgumentError) expected stream :projects to be a struct or map with :id key, got: [...]
If you would like to generate custom DOM id's based on other keys, use stream_configure/3 with the :dom_id option beforehand.

I’m using the exact same function to set the initial stream that I’m attempting to use for the replacement, which is: projects = Projects.list_projects()
The handle_event/3 shuffles the order of the projects, so I don’t want to manually delete and insert each project that gets shuffled.

Here’s the mount code:

  def mount(_params, _session, socket) do
    form = Projects.change_order() |> to_form()
    projects = Projects.list_projects()

    socket =
      socket
      |> assign(form: form, project_list: projects)

    {:ok, stream(socket, :projects, projects)}
  end

and handle_event:

  def handle_event(
        "re-order",
        %{"project" => %{"id" => id, "order" => order, "original_order" => orig}},
        socket
      ) do
    id_int = if id != "", do: String.to_integer(id), else: nil
    order_int = if order != "", do: String.to_integer(order), else: nil
    orig_int = if orig != "", do: String.to_integer(orig), else: nil

    if order_int == orig_int || (is_nil(id_int) && is_nil(orig_int)) do
      {:noreply, socket}
    else
      if is_nil(orig_int) do
        Projects.update_order(id_int, order_int)
      else
        Projects.shuffle(orig_int, order_int)
      end

      form = Projects.change_order() |> to_form()
      projects = Projects.list_projects()

      socket =
        socket
        |> assign(form: form, project_list: projects)

      {:noreply, stream_insert(socket, :projects, projects, reset: true)}
    end
  end

Am I missing something obvious?

2

To update multiple items you use stream/4, not stream_insert/4 :wink:

The error is telling you that it expects a single struct/map and got a list.

3

Ah yes, minor details :sweat_smile: idk how I completely misread that. Thanks!