class GraphQL::Schema::Validator::LengthValidator

Use this to enforce a .length restriction on incoming values. It works for both Strings and Lists.

Examples

Example: Allow no more than 10 IDs

argument :ids, [ID], required: true, validates: { length: { maximum: 10 } }

Example: Require three selections

argument :ice_cream_preferences, [ICE_CREAM_FLAVOR], required: true, validates: { length: { is: 3 } }

Public Class Methods

initialize(Integer maximum:, String too_long:)

Source

# File lib/graphql/schema/validator/length_validator.rb, line 36
def initialize(
  maximum: nil, too_long: "%{validated} is too long (maximum is %{count})",
  minimum: nil, too_short: "%{validated} is too short (minimum is %{count})",
  is: nil, within: nil, wrong_length: "%{validated} is the wrong length (should be %{count})",
  message: nil,
  **default_options
)
  if within && (minimum || maximum)
    raise ArgumentError, "`length: { ... }` may include `within:` _or_ `minimum:`/`maximum:`, but not both"
  end
  # Under the hood, `within` is decomposed into `minimum` and `maximum`
  @maximum = maximum || (within && within.max)
  @too_long = message || too_long
  @minimum = minimum || (within && within.min)
  @too_short = message || too_short
  @is = is
  @wrong_length = message || wrong_length
  super(**default_options)
end

Parameters

maximum (Integer)
too_long (String) — Used when maximum is exceeded or value is greater than within
minimum (Integer)
too_short (String) — Used with value is less than minimum or less than within
is (Integer) — Exact length requirement
wrong_length (String) — Used when value doesn’t match is
within (Range) — An allowed range (becomes minimum: and maximum: under the hood)
message (String)

Calls superclass method GraphQL::Schema::Validator::new

Public Instance Methods

validate (_object, _context, value)

Source

# File lib/graphql/schema/validator/length_validator.rb, line 56
def validate(_object, _context, value)
  return if permitted_empty_value?(value) # pass in this case
  length = value.nil? ? 0 : value.length
  if (current_max = validation_parameter(@maximum)) && length > current_max
    partial_format(validation_parameter(@too_long), { count: current_max })
  elsif (current_min = validation_parameter(@minimum)) && length < current_min
    partial_format(validation_parameter(@too_short), { count: current_min })
  elsif (current_is = validation_parameter(@is)) && length != current_is
    partial_format(validation_parameter(@wrong_length), { count: current_is })
  end
end