Snowflake ID for Users

Snowflake ID is a format first developed by Twitter in 2010 and has been modified and used by other platforms. It uses Unix epoch time, and machine or shards and is applied to micro-blog posts (Tweets etc), users, media etc etc.

Using Snowflake ID's assigned to content (micro-blog posts) you can lookup content before and after.

I have used the Elixir Snowflake package and applied a simple Snowflake handler for content.

defmodule Folkbot.Accounts.User do
  use Ecto.Schema
  import Ecto.Changeset
  alias Folkbot.Snowflaker

  schema "users" do
    field :admin, :boolean, default: false
    field :banner_image, :string
    field :bio, :string
    field :editor, :boolean, default: false
    field :email, :string
    field :first_name, :string
    field :host, :boolean, default: false
    field :last_name, :string
    field :location, :string
    field :profile_image, :string
    field :seller, :boolean, default: false
    field :slug, :string
    field :snowflake, :string
    field :tagline, :string
    field :username, :string
    field :website, :string

    timestamps()
  end

  @doc false
  def changeset(user, attrs) do
    user
    |> cast(attrs, [
      :username,
      :first_name,
      :last_name,
      :slug,
      :email,
      :bio,
      :location,
      :website,
      :profile_image,
      :banner_image,
      :tagline,
      :snowflake,
      :admin,
      :editor,
      :host,
      :seller])
    |> validate_required([
      :username,
      :email,
      :website,
      :admin,
      :editor,
      :host,
      :seller])
    |> snowflake_for_new_user()
  end

  def snowflake_for_new_user(changeset) do
    Snowflaker.snowflake_for_new_content(changeset)
  end

end

The Snowflaker module

defmodule Folkbot.Snowflaker do
  import Ecto.Changeset
  @moduledoc false

  def next_snowflake() do
    {:ok, snowflake} = Snowflake.next_id()
    to_string(snowflake)
  end

  def snowflake_for_new_content(changeset) do
    snowflake = next_snowflake()
    put_change(changeset, :snowflake, snowflake)
  end

end

Now whenever a user is created, a Snowflake ID is also created.

I have created a helper script lib/folkbot_web/scripts/user.iex.exs

import Ecto.Query
import Plug.Conn
use Ecto.Schema
import Ecto.Changeset
alias Folkbot.Accounts
alias Folkbot.Accounts.User

time = DateTime.now!("Europe/Copenhagen")
random = Enum.random(0..100000)
user_params = %{
  username: "niccolox#{random}}",
  website: "devekko.com",
  email: "niccolox#{random}@devekko.com",
  admin: true,
  editor: true,
  seller: true,
  host: true
}
Accounts.create_user(user_params)

Gives us

iex(9)> random = Enum.random(0..100000)
3772
iex(10)> user_params = %{
...(10)>   username: "niccolox#{random}}",
...(10)>   website: "devekko.com",
...(10)>   email: "niccolox#{random}@devekko.com",
...(10)>   admin: true,
...(10)>   editor: true,
...(10)>   seller: true,
...(10)>   host: true
...(10)> }
%{
  admin: true,
  editor: true,
  email: "[email protected]",
  host: true,
  seller: true,
  username: "niccolox3772}",
  website: "devekko.com"
}
iex(11)> Accounts.create_user(user_params)
[debug] QUERY OK db=19.4ms decode=2.2ms queue=0.8ms idle=851.0ms
INSERT INTO "users" ("admin","editor","email","host","seller","snowflake","username","website","inserted_at","updated_at") VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10) RETURNING "id" [true, true, "[email protected]", true, true, "6831485532917207040", "niccolox3772}", "devekko.com", ~N[2021-08-31 04:16:13], ~N[2021-08-31 04:16:13]]
{:ok,
 %Folkbot.Accounts.User{
   __meta__: #Ecto.Schema.Metadata<:loaded, "users">,
   admin: true,
   banner_image: nil,
   bio: nil,
   editor: true,
   email: "[email protected]",
   first_name: nil,
   host: true,
   id: 2,
   inserted_at: ~N[2021-08-31 04:16:13],
   last_name: nil,
   location: nil,
   profile_image: nil,
   seller: true,
   slug: nil,
   snowflake: "6831485532917207040",
   tagline: nil,
   updated_at: ~N[2021-08-31 04:16:13],
   username: "niccolox3772}",
   website: "devekko.com"
 }}

Snowflake functions can work on Snowflake ID's https://hexdocs.pm/snowflake/

Snowflake.Helper.epoch()
1630299375
iex(2)> Snowflake.Helper.machine_id()
1
iex(3)> Snowflake.Util.timestamp_of_id(6831482055310708736)
1628752244785
iex(4)> Snowflake.Util.real_timestamp_of_id(6831482055310708736)
1630382544160
iex(14)> Snowflake.Util.real_timestamp_of_id(6831482055310708736) |> DateTime.from_unix!(:millisecond)
~U[2021-08-31 04:02:24.160Z]

iex(31)> alias Folkbot.Snowflaker                                      
Folkbot.Snowflaker
iex(32)> snowflakeid = Snowflaker.next_snowflake() |> String.to_integer
6831521411299807232
iex(33)> Snowflake.Util.real_timestamp_of_id(snowflakeid) |> DateTime.from_unix!(:millisecond)
~U[2021-08-31 06:38:47.359Z]

Git commit: https://github.com/FolkBot/folkbot/commit/3d5ad7bef0253f14d3a78a5eebda093f97a9ce16