Allow registering via a registry

[vhgn]

Description

Allows to use SurrealEx with a Registry without any wrapper

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[vhgn]

I was not able to run the tests locally, but it worked in a separate project

defmodule Db do
  def exec(id, statement, bindings) do
    with {:ok, [result]} <- exec_many(id, statement, bindings) do
      {:ok, result}
    end
  end

  def exec_many(id, statement, bindings) do
    with {:ok, %SurrealEx.Domain.ExecutionSuccess{result: result}} <-
           SurrealEx.query(via(id), statement, bindings) do
      {:ok, result}
    end
  end

  def start(id) do
    {namespace, database} = get_info(id)

    DynamicSupervisor.start_child(
      Db.DynamicSupervisor,
      {SurrealEx.Socket, name: via(id), database: database, namespace: namespace}
    )
  end

  def started?(id) do
    case Registry.lookup(Db.Registry, id) do
      [] -> false
      _ -> true
    end
  end

  defp via(id) do
    {:via, Registry, {Db.Registry, id}}
  end

  defp get_info({namespace, database}) do
    {"#{Mix.env()}_#{namespace}", to_string(database)}
  end

  defp get_info(namespace) do
    {"#{Mix.env()}_#{namespace}", "main"}
  end
end