phoenixframework / phoenix_template Goto Github PK

When writing a new controller and "html module" (is there an official name for the module that calls use HelloPhxWeb, :html?) it's possible either forget to define the html module completely or mistype the name, possibly because of not realizing that capitalization is important.

This is something that just happened to me as I was porting one of my simple phoenix apps to 1.7 and the new HTML structures. In my case my html module was named PrsHTML when it should have been PRsHTML.

I've also seen it happen to others such as this forum post where the user's module name was MyAppWeb.UserSettingsHtml instead of MyAppWeb.UserSettingsHTML
https://elixirforum.com/t/random-no-html-template-defined-for-myappweb-html-errors-after-upgrading-to-phoenix-1-7/54814

The current error message looks like: no "game" html template defined for HelloPhxWeb.GameHTML

I think this error handling can be improved by verifying that the module contained in the error message is a real existing module.

My proposed error message in the case that the module is not defined would look something like: Looked for a HelloPhxWeb.GameHTML HTML module, but none was defined.

Ideally we'd link to a relevant page in the docs to help user's understand what an html module is, the inflection rules, and an example. But I'm not sure if there is a page like that in the docs currently.

Also ideally we could use String.jaro_distance/2 to let the user know if they possibly made a typo when defining their module (especially if it's just a casing issue!).

Here's an example repo that showcases the error: https://github.com/axelson/phoenix_template_error_example
Start the phoenix server and navigate to http://localhost:4000/game to see the error

Use Case

When building up a tree of templates for rendering templates (like emails in the example below), it would be nice to use a :prefix option to generate function names in nested directories without having to leave component module files in said nested directories.

defmodule EmailHTML do
  use Phoenix.Component

  embed_templates "templates/email/admin/*.html", prefix: "admin_", suffix: "_html"
  embed_templates "templates/email/user/*.html", prefix: "user_", suffix: "_html"
end

Implementation

If I am understanding how things are currently implemented, I believe this would involve modifying this section of code here:

to look something like this:

  defmacro embed_templates(pattern, opts \\ []) do
    quote bind_quoted: [pattern: pattern, opts: opts] do
      Phoenix.Template.compile_all(
        &Phoenix.Template.__embed__(&1, opts[:prefix], opts[:suffix]),
        Path.expand(opts[:root] || __DIR__, __DIR__),
        pattern
      )
    end
  end

  @doc false
  def __embed__(path, prefix, suffix) do
      rootname = path
        |> Path.basename()
        |> Path.rootname()
        |> Path.rootname()
      (prefix || "")
      |> Kernel.<>(rootname)
      |> Kernel.<>(suffix || "")
  end

Acknowledgements

Admittedly, I am relatively new to Phoenix/Elixir rendered views. If I am approaching this problem incorrectly, or am unaware of some far-reaching implications this change may have, I would gladly welcome correction to my approach.