Class: GraphQL::Schema::Validator::LengthValidator

Inherits:
Validator
  • Object
show all
Defined in:
lib/graphql/schema/validator/length_validator.rb

Overview

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

Examples:

Allow no more than 10 IDs


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

Require three selections


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

Instance Method Summary collapse

Constructor Details

#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) ⇒ LengthValidator

Returns a new instance of LengthValidator.

Parameters:

  • maximum (Integer) (defaults to: nil)
  • too_long (String) (defaults to: "%{validated} is too long (maximum is %{count})") —

    Used when maximum is exceeded or value is greater than within

  • minimum (Integer) (defaults to: nil)
  • too_short (String) (defaults to: "%{validated} is too short (minimum is %{count})") —

    Used with value is less than minimum or less than within

  • is (Integer) (defaults to: nil) —

    Exact length requirement

  • wrong_length (String) (defaults to: "%{validated} is the wrong length (should be %{count})") —

    Used when value doesn't match is

  • within (Range) (defaults to: nil) —

    An allowed range (becomes minimum: and maximum: under the hood)

  • message (String) (defaults to: nil) 


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# File 'lib/graphql/schema/validator/length_validator.rb', line 25

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

Instance Method Details

#validate(_object, _context, value) ⇒ Object 



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# File 'lib/graphql/schema/validator/length_validator.rb', line 45

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