Lit

Lit is a rapid admin generator for Phoenix apps. It creates custom templates and relies on the Phoenix html generator under the hood.

Installation

To install Lit, perform the following steps:

1. Add lit to your list of dependencies in mix.exs. Then, run mix deps.get:

def deps do
  [
    {:lit, "~> 3.4"}
  ]
end

2. Add a Plug.Static plug to your endpoint.ex:

plug(
  Plug.Static,
  at: "/lit",
  from: {:lit, "priv/static"},
  gzip: true,
  cache_control_for_etags: "public, max-age=86400"
)

3. Configure Lit by adding the following to your config.exs.

config :lit,
  otp_app: :my_app_name,
  template_format: "eex" || "slime"

4. Run mix lit.install

NOTE: You can also choose to use slime templates, but you will need to first install Phoenix Slime and then update your configuration to specify template_format: "slime".

Now you're ready to start generating your admin! :tada:

Usage

Lit uses Phoenix generators under the hood. Lit injects it's own custom templates into your priv/static directory, then runs the mix phx.gen.html task with the options you passed in. Finally, it uninstalls the custom templates so they don't interfere with running the plain Phoenix generators.

In light of that fact, the lit.gen.html task takes all the same arguments as the phx.gen.html, but does some extra configuration on either end. Checkout mix help phx.gen.html for more details about the supported options and format.

For example, if we wanted to generate a blog with a Post model we could run the following command:

$ mix lit.gen.html Blog Post posts title:string body:text published_at:datetime published:boolean views:integer

The output would look like:

Add the resource to your browser scope in lib/my_app_web/router.ex:

    resources "/posts", PostController

Ensure the following is added to your endpoint.ex:

    plug(
      Plug.Static,
      at: "/lit",
      from: {:lit, "priv/static"},
      gzip: true,
      cache_control_for_etags: "public, max-age=86400",
      headers: [{"access-control-allow-origin", "*"}]
    )

  :fire: Lit generated html for Posts! :fire:

Lit also installed an admin layout into your my_app_web/templates/layout/lit.html.eex. You will want to update it to include your new navigation link:

<nav class="lit-nav">
  <a href="/posts">Posts</a>
</nav>

There may be times when you are adding Lit into an already existing system where your application already contains the modules and controllers and you just want to use the Lit admin interface. Since the lit.gen mix tasks are just wrappers around the existing phx.gen tasks, you can use most of the same flags. To add an admin interface for Posts in the previous example, where the model and controller modules already exist, use the following command:

$ mix lit.gen.html Blog Post posts --no-schema --no-context --web Admin title:string body:text published_at:datetime published:boolean views:integer

Association filters

Lit does not support association filters at this time. Filtrex does not yet support them.

You can checkout these two issues to see the latest updates:

https://github.com/rcdilorenzo/filtrex/issues/55

https://github.com/rcdilorenzo/filtrex/issues/38

However, that does not mean you can't roll your own.

Example

We have a Accounts.User model that has_many :credentials, Accounts.Credential and we want to support filtering users by credentials.email.

1. Update the Accounts domain.

# accounts.ex
...
defp do_paginate_users(filter, params) do
  credential_params = Map.get(params, "credentials")
  params = Map.drop(params, ["credentials"])

  User
  |> Filtrex.query(filter)
  |> credential_filters(credential_params)
  |> order_by(^sort(params))
  |> paginate(Repo, params, @pagination)
end

defp credential_filters(query, nil), do: query

defp credential_filters(query, params) do
  search_string = "%#{params["email"]}%"

  from(u in query,
    join: c in assoc(u, :credentials),
    where: like(c.email, ^search_string),
    group_by: u.id
  )
end
...

2. Update form filters.

# users/index.html.eex
<div class="field">
  <label>Credential email</label>
  <%= text_input(:credentials, :email, value: maybe(@conn.params, ["credentials", "email"])) %>
</div>

Note: You'll need to install & import Maybe into your views {:maybe, "~> 1.0.0"} for the above eex to work.

Styling

Lit generates two CSS themes you can use: base.css & theme.css. The base styles are basically bare bones, and the theme styles look like the screenshot above. Just change the stylesheet link in the lit.html.eex layout.

If you want to use the theme, but override the colors, you'll need to include your own stylesheet with the specific overrides.

Internationalization

Lit comes with .po files for en, ru, es and de locales. If you are using lit and can provide us with translation files for other languages, please submit a Pull Request with the translation file. We'd love to add as many translations as possible.

If you wish to add your own customized translations, you can configure Lit to use your own custom MessagesBackend and adding it in your Lit configuration settings in config.exs. You can find the all messages that can be customized in the default i18n/backend.ex file.

If you are customizing a backend for a "standard" spoken language, please submit back a proper .po translation file for us to include in the official Lit releases so other users can take advantage.

Example

defmodule MyApp.CustomMessagesBackend do
  def message("Contains"), do: "** CUSTOM Contains **"
  def message("Equals"), do: "** CUSTOM Equals ****"
  def message("< Prev"), do: "<--"
  def message("Next >"), do: "-->"

  # You can add a fallback so it won't break with newly added messages or
  # messages you did not customize
  def message(text), do: Lit.I18n.Backend.message(text)
end

# config.exs
config :lit,
  otp_app: :my_app_name,
  i18n_backend: MyApp.CustomMessagesBackend
  template_format: "eex" || "slime"