aardbei/app/controllers/api/groups_contr...

# Provides API views to read information related to Groups.
# This controller provides two methods to authenticate and authorize a request:
#   - By the Session used to authenticate logged-in users, and
#   - By passing a custom Authorization:-header of the form 'Group :api_key'.
#
# If the API key method is used, the :id parameter is ignored, but still required in the URL.
class Api::GroupsController < ApiController
  has_no_group = [:index]

  # Session-based authentication / authorization filters
  before_action :set_group,           except: has_no_group
  before_action :require_membership!, except: has_no_group
  before_action :api_require_admin!,  only:   has_no_group
  skip_before_action :set_group, :require_membership!, :api_require_authentication!, if: 'request.authorization'

  # API key based filter (both authenticates and authorizes)
  before_action :api_auth_group_token, if: 'request.authorization'

  # GET /api/groups
  def index
    @groups = Group.all
  end

  # GET /api/groups/1
  def show; end

  # GET /api/groups/1/current_activities
  def current_activities
    reference = try_parse_datetime params[:reference]
    @activities = @group.current_activities reference

    render 'api/activities/index'
  end

  # GET /api/groups/1/upcoming_activities
  def upcoming_activities
    reference = try_parse_datetime params[:reference]
    @activities = @group.upcoming_activities reference

    render 'api/activities/index'
  end

  # GET /api/groups/1/previous_activities
  def previous_activities
    reference = try_parse_datetime params[:reference]
    @activities = @group.previous_activities reference

    render 'api/activities/index'
  end

  private

  # Set group from the :id parameter.
  def set_group
    @group = Group.find(params[:id])
  end

  # @return [DateTime] the parsed input.
  def try_parse_datetime(input = nil)
    return unless input

    begin
      DateTime.parse input
    rescue ArgumentError
      nil
    end
  end
end