AshSqids

Sqids type for Ash framework.

For what are Sqids and why would you want to use them I recommend looking at the linked website. But basically it is a pretty presentation for integer type. You might prefer having url like /rooms/DcHPs over /rooms/151 or /rooms/48922bf6-c418-4023-a478-0cca4dd04e68.

The library consists of a single module AshSqids.Type that provides Ash.Type implementation.

Installation

Add to the deps, get deps (mix deps.get), compile them (mix deps.compile).

def deps do
  [
    {:ash_sqids, "~> 0.0.1"},
  ]
end

Usage

Define a module that will represent a Sqid type and use AshSqids.Type in it. Provide configuration for it in config :ash_sqids, :opts. And then use it as type in attributes and arguments.

# lib/example/posts/resources/comment.ex
defmodule Example.Posts.Comment do
  use Ash.Resource, data_layer: AshPostgres.DataLayer

  # 1) define a type module
  defmodule Id, do: use(AshSqids.Type)

  attributes do
    # 2) use it as an attribute type
    integer_primary_key :id, type: Id

    # ...
  end

  relationships do
    # 3) use as `attribute_type` in `belongs_to` like this
    belongs_to :post, Example.Posts.Post, attribute_type: Example.Posts.Post.Id
  end
end

Primary key

As shown if you want to use it as a primary key (main use case) then add integer_primary_key with type option.

And don't forget attribute_type in belongs_to for references to a resource with sqids.

Config

Here is how mentioned config is supposed to look:

# config/config.exs
import Config

config :ash_sqids, :opts, [
  {Example.Posts.Comment.Id, []}, # use default options
  {Example.Posts.Post.Id, min_length: 7} # some custom values
]

Options are passed into Sqids.new! and at the time of writing there are three options there - alphabet, min_length and blocklist.

It is better to provide alphabet. It can be a default one - abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 - but just shuffled.

use AshSqids.Type accepts optional config option that allows you to reuse configurations. So if in the example we wanted for comments ids and posts ids to be in the same style then we could do it like this:

# `config` is an atom (defaulting to a module name) that will be used as a key
# to look up Sqids options from `config :ash_sqids, :opts`
defmodule Id, do: use(AshSqids.Type, config: Example.Posts.Post.Id)

Protocols

AshSqids.Type provides implementation for following protocols:

• String.Chars - so "#{id}" results in a sqid string.
• Jason.Encoder - same, returns a sqid string.
• Inspect - with the format of #Example.Posts.Comment.Id<1, "Uk">.

References

Sqids - website, github, elixir library.

Ash - website, github, Ash.Type docs.