error_example.rb

class CustomError < StandardError
  # custom options to GraphQLError
  def options
  end
end

class MuationError < CustomError
  def initialize(key)
    @key = key
    message = I18n.t(key, scope: 'mutations.errors')
  end
end

class ModelError < CustomError
  def initialize(key, record)
    @key = key
    @record = record
    message = I18n.t(key, scope: 'models.errors')
  end
end

raise MutationError, :login_error

raise ModelError, :invalid, record

errors.zh-CN.yml

zh-CN:
  mutations:
    errors:
      login_error: 登录异常
  models:
    errors:
      product:
        invalid: xx问题

rescuable.rb

class Rescuable
  def initialize(resolve_func)
    @resolve_func = resolve_func
  end

  def call(obj, args, ctx)
    @resolve_func.call(obj, args, ctx)
  rescue CustomError => err
    GraphQL::ExecutionError.new(err.message, options: err.options)
  rescue ActiveRecord::RecordNotFound => err
    detail = err.id ? " with id #{err.id}" : ''
    GraphQL::ExecutionError.new("#{err.model} record not found#{detail}")
  rescue ActiveRecord::RecordInvalid => err
    GraphQL::ExecutionError.new(err.message)
  rescue StandardError => err
    GraphQL::ExecutionError.new("Unexpected error: #{err.message}")
  end
end