Module: Grape::Validations::Types

Defined in:
lib/grape/validations/types.rb,
lib/grape/validations/types/file.rb,
lib/grape/validations/types/json.rb,
lib/grape/validations/types/set_coercer.rb,
lib/grape/validations/types/array_coercer.rb,
lib/grape/validations/types/build_coercer.rb,
lib/grape/validations/types/invalid_value.rb,
lib/grape/validations/types/dry_type_coercer.rb,
lib/grape/validations/types/primitive_coercer.rb,
lib/grape/validations/types/custom_type_coercer.rb,
lib/grape/validations/types/multiple_type_coercer.rb,
lib/grape/validations/types/variant_collection_coercer.rb,
lib/grape/validations/types/custom_type_collection_coercer.rb

Overview

Module for code related to grape’s system for coercion and type validation of incoming request parameters.

Grape uses a number of tests and assertions to work out exactly how a parameter should be handled, based on the type and coerce_with options that may be supplied to Dsl::Parameters#requires and Dsl::Parameters#optional. The main entry point for this process is Types.build_coercer.

Defined Under Namespace

Modules: BuildCoercer Classes: ArrayCoercer, CustomTypeCoercer, CustomTypeCollectionCoercer, DryTypeCoercer, File, InvalidValue, Json, JsonArray, MultipleTypeCoercer, PrimitiveCoercer, SetCoercer, VariantCollectionCoercer

Constant Summary collapse

PRIMITIVES =
[
  # Numerical
  Integer,
  Float,
  BigDecimal,
  Numeric,

  # Date/time
  Date,
  DateTime,
  Time,

  # Misc
  Grape::API::Boolean,
  String,
  Symbol,
  TrueClass,
  FalseClass
].freeze
STRUCTURES =

Types representing data structures.

[Hash, Array, Set].freeze
SPECIAL =
{
  ::JSON => Json,
  Array[JSON] => JsonArray,
  ::File => File,
  Rack::Multipart::UploadedFile => File
}.freeze
GROUPS =
[Array, Hash, JSON, Array[JSON]].freeze

Class Method Summary collapse

Class Method Details

.build_coercer(type, method: nil, strict: false) ⇒ Object

Chooses the best coercer for the given type. For example, if the type is Integer, it will return a coercer which will be able to coerce a value to the integer.

There are a few very special coercers which might be returned.

Grape::Types::MultipleTypeCoercer is a coercer which is returned when the given type implies values in an array with different types. For example, [Integer, String] allows integer and string values in an array.

Grape::Types::CustomTypeCoercer is a coercer which is returned when a method is specified by a user with coerce_with option or the user specifies a custom type which implements requirments of Grape::Types::CustomTypeCoercer.

Grape::Types::CustomTypeCollectionCoercer is a very similar to the previous one, but it expects an array or set of values having a custom type implemented by the user.

There is also a group of custom types implemented by Grape, check Grape::Validations::Types::SPECIAL to get the full list.



157
158
159
160
161
# File 'lib/grape/validations/types.rb', line 157

def build_coercer(type, method: nil, strict: false)
  cache_instance(type, method, strict) do
    create_coercer_instance(type, method, strict)
  end
end

.cache_instance(type, method, strict, &_block) ⇒ Object



187
188
189
190
191
192
193
194
195
196
197
198
199
# File 'lib/grape/validations/types.rb', line 187

def cache_instance(type, method, strict, &_block)
  key = cache_key(type, method, strict)

  return @__cache[key] if @__cache.key?(key)

  instance = yield

  @__cache_write_lock.synchronize do
    @__cache[key] = instance
  end

  instance
end

.cache_key(type, method, strict) ⇒ Object



201
202
203
204
205
206
207
# File 'lib/grape/validations/types.rb', line 201

def cache_key(type, method, strict)
  [type, method, strict].each_with_object(+'_') do |val, memo|
    next if val.nil?

    memo << '_' << val.to_s
  end
end

.collection_of_custom?(type) ⇒ Boolean

Is the declared type an Array or Set of a #custom? type?



119
120
121
122
123
# File 'lib/grape/validations/types.rb', line 119

def collection_of_custom?(type)
  (type.is_a?(Array) || type.is_a?(Set)) &&
    type.length == 1 &&
    (custom?(type.first) || special?(type.first))
end

.create_coercer_instance(type, method, strict) ⇒ Object



163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
# File 'lib/grape/validations/types.rb', line 163

def create_coercer_instance(type, method, strict)
  # Maps a custom type provided by Grape, it doesn't map types wrapped by collections!!!
  type = Types.map_special(type)

  # Use a special coercer for multiply-typed parameters.
  if Types.multiple?(type)
    MultipleTypeCoercer.new(type, method)

    # Use a special coercer for custom types and coercion methods.
  elsif method || Types.custom?(type)
    CustomTypeCoercer.new(type, method)

    # Special coercer for collections of types that implement a parse method.
    # CustomTypeCoercer (above) already handles such types when an explicit coercion
    # method is supplied.
  elsif Types.collection_of_custom?(type)
    Types::CustomTypeCollectionCoercer.new(
      Types.map_special(type.first), type.is_a?(Set)
    )
  else
    DryTypeCoercer.coercer_instance_for(type, strict)
  end
end

.custom?(type) ⇒ Boolean

A valid custom type must implement a class-level ‘parse` method, taking one String argument and returning the parsed value in its correct type.



106
107
108
109
110
111
112
# File 'lib/grape/validations/types.rb', line 106

def custom?(type)
  !primitive?(type) &&
    !structure?(type) &&
    !multiple?(type) &&
    type.respond_to?(:parse) &&
    type.method(:parse).arity == 1
end

.group?(type) ⇒ Boolean

Is the declared type a supported group type? Currently supported group types are Array, Hash, JSON, and Array



97
98
99
# File 'lib/grape/validations/types.rb', line 97

def group?(type)
  GROUPS.include? type
end

.map_special(type) ⇒ Object



125
126
127
# File 'lib/grape/validations/types.rb', line 125

def map_special(type)
  SPECIAL.fetch(type, type)
end

.multiple?(type) ⇒ Boolean

Is the declared type in fact an array of multiple allowed types? For example the declaration types: [Integer,String] will attempt first to coerce given values to integer, but will also accept any other string.



77
78
79
# File 'lib/grape/validations/types.rb', line 77

def multiple?(type)
  (type.is_a?(Array) || type.is_a?(Set)) && type.size > 1
end

.primitive?(type) ⇒ Boolean

Is the given class a primitive type as recognized by Grape?



55
56
57
# File 'lib/grape/validations/types.rb', line 55

def primitive?(type)
  PRIMITIVES.include?(type)
end

.special?(type) ⇒ Boolean

Does Grape provide special coercion and validation routines for the given class? This does not include automatic handling for primitives, structures and otherwise recognized types. See SPECIAL.



88
89
90
# File 'lib/grape/validations/types.rb', line 88

def special?(type)
  SPECIAL.key? type
end

.structure?(type) ⇒ Boolean

Is the given class a standard data structure (collection or map) as recognized by Grape?



65
66
67
# File 'lib/grape/validations/types.rb', line 65

def structure?(type)
  STRUCTURES.include?(type)
end