Liquid implementation in elixir


License
MIT

Documentation

Liquid Hex.pm Hex.pm Build Status

It's a templating library for Elixir. Continuation of the fluid liquid conversion.

Usage

Add the dependency to your mix file:

# mix.exs
defp deps do
  […,
   {:liquid, "~> 0.8.0"}]
end

You can either start the application directly:

Liquid.start

Or start it with your application:

# mix.exs
def application do
  [mod: {MyApp, []},
   applications: […, :liquid]]
end

Compile a template from a string:

template = Liquid.Template.parse("{% assign hello='hello' %}{{ hello }}{{world}}")

Render the template with a keyword list representing the local variables:

{ :ok, rendered, _ } = Liquid.Template.render(template, %{"world" => "world"})

For registers you might want to use in custom tags you can assign them like this:

{ :ok, rendered, _ } = Liquid.Template.render(template, %{"world" => "world"}, registers: %{test: "hallo")

The tests should give a pretty good idea of the features implemented so far.

Custom tags and filters

You can add your own filters and tags/blocks inside your project:

defmodule MyFilters do
  def meaning_of_life(_), do: 42
  def one(_), do: 1
end

defmodule ExampleTag do
  def parse(%Liquid.Tag{}=tag, %Liquid.Template{}=context) do
    {tag, context}
  end

  def render(output, tag, context) do
    number = tag.markup |> Integer.parse |> elem(0)
    {["#{number - 1}"] ++ output, context}
  end
end

defmodule ExampleBlock do
  def parse(b, p), do: { b, p }
end

and than include them in your config.exs file

# config.exs
config :liquid,
  extra_filter_modules: [MyFilters],
  extra_tags: %{minus_one: {ExampleTag, Liquid.Tag},
                my_block: {ExampleBlock, Liquid.Block}}

Another option is to set up the tag using: Liquid.Registers.register("minus_one", MinusOneTag, Tag) for tag Liquid.Registers.register("my_block", ExampleBlock, Liquid.Block) same for blocks; and for filters you should use Liquid.Filters.add_filters(MyFilters)

Global Filters

It's also possible to apply global filter to all rendered variables setting up the config:

# config.exs
config :liquid,
  global_filter: &MyFilter.counting_sheeps/1

or adding a "global_filter" value to context for Liquid.Template.render function: Liquid.Template.render(tpl, %{global_filter: &MyFilter.counting_sheeps/1}) (you need to define filter function first)

File systems

You can also set up the desired default file system for your project using the config.exs file

# config.exs
config :liquid,
  file_system: {Liquid.LocalFileSystem, "/your/path"}

Context assignment

Liquid.Matcher protocol is designed to deal with your custom data types you want to assign For example having the following struct:

defmodule User do
  defstruct name: "John", age: 27, about: []
end

You can describe how to get the data from it:

defimpl Liquid.Matcher, for: User do
  def match(current, ["info"|_]=parts) do
    "His name is: "<> current.name
  end
end

And later you can use it in your code:

iex> "{{ info }}" |> Liquid.Template.parse |> Liquid.Template.render(%User{}) |> elem(1)
"His name is: John"

Missing Features

Feel free to add a bug report or pull request if you feel that anything is missing.

todo

  • Fix empty check on arrays