Programming Phoenix LiveView B9.0: Generated code uses streams in LiveView 0.19.x so example code no longer works (p. 94)

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Since LiveView now supports Streams, the generated code seems to be pushing the user in that direction as well.

As a result, the example code starting on page 94 (in the “Mount and Render the Product Index” section) no longer matches the code created when I run the generator.

It’s not difficult to work around, but the section should definitely be updated to match the new generator code IMO.

This code from the book:

def mount(_params, _session, socket) do
  {:ok, assign(socket, :products, list_products())}
end

# ...

defp list_products do
  Catalog.list_products()
end

Looks more like this in my generated code:

@impl true
def mount(_params, _session, socket) do
  {:ok, stream(socket, :products, Catalog.list_products())}
end

# ...

defp apply_action(socket, :index, _params) do
  socket
  |> assign(:page_title, "Listing Products")
  |> assign(:product, nil)
end

This code from the book showing how to add data to the socket becomes a little confusing as a result:

def mount(_params, _session, socket) do
  {:ok,
    socket
    |> assign(:greeting, "Welcome to Pento!") # add this line
    |> assign(:products, list_products())}
  end

I ended up doing this instead:

@impl true
def mount(_params, _session, socket) do
  socket = assign(socket, :greeting, "Welcome to Pento!")
  {:ok, stream(socket, :products, Catalog.list_products())}
end

Similar outdated function references occur on page 96.

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