beautiful_atrocity.rb

class Endpoint
  class << self
    def authorized
      undef_method :"authorized?" if method_defined? :"authorized?"
      define_method(:"authorized?") { true }
    end

    def segments(*segs)
      undef_method :segments if method_defined? :segments
      define_method(:segments) { segs }
    end

    def params(*ps)
      undef_method :params if method_defined? :params
      ps_hash = ps.map { |p| [p, p] }.to_h
      define_method(:params) { ps_hash }
    end
  end

  def authorized?
    false
  end

  def segments
    raise "No segments defined"
  end

  def params
    {}
  end

  def path(context)
    segments.map { |seg| seg.is_a?(Symbol) ? context.fetch(seg) : seg }
  end

  def full_params(context)
    ps = params
    ps.merge!({ access_token: :token}) if authorized?
    ps.transform_values { |v| v.is_a?(Symbol) ? context.fetch(v) : v }
  end

  def request(**context)
    Request.new path: path(context), params: full_params(context)
  end

  def self.request(**context)
    self.new.request(**context)
  end
end

class GuildUpgrade < Endpoint
  segments 'guild', 'upgrades', :id
end

class GuildUpgrades < Endpoint
  segments 'guild', 'upgrades'
  params :ids
end

class GuildTreasury < Endpoint
  authorized
  segments 'guild', :id, 'treasury'
end

# Called as follows:

GuildUpgrade.request id: 
GuildUpgrades.request ids: '38,55,58'
GuildTreasury.request id: 'my-guild-id', token: 'my-api-token'