class ParamsDeserializer

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice,

this list of conditions and the following disclaimer.

Redistributions in binary form must reproduce the above copyright notice,

this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

Neither the name of the copyright holder nor the names of its contributors

may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS” AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice,

this list of conditions and the following disclaimer.

Redistributions in binary form must reproduce the above copyright notice,

this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

Neither the name of the copyright holder nor the names of its contributors

may be used to endorse or promote products derived from this software without specific prior written permission.

Attributes

format_keys[RW]

key_format[RW]

root_key[R]

strict[RW]

strict_mode[RW]

params[R]

Public Class Methods

new(params) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 37
def initialize(params)
  @params = params
  verify_root_key_exists
  verify_valid_keys
end

Private Class Methods

attribute(attr, options = {}) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 121
def attribute(attr, options = {})
  define_getter_method(attr, options) do
    params_root[attr]
  end
end

attributes(*args) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 133
def attributes(*args)
  args.each do |attr|
    attribute(attr)
  end
end

attrs() click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 117
def attrs
  @attrs ||= AttributeCollection.new
end

define_getter_method(attr, options = {}, &block) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 160
def define_getter_method(attr, options = {}, &block)
  options[:rename_to] ||= attr
  attrs << Attribute.new(attr, options)
  define_method(options[:rename_to], &block) unless method_defined?(options[:rename_to])
end

deserialize(params) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 113
def deserialize(params)
  new(params).deserialize
end

has_many(attr, options = {}) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 139
def has_many(attr, options = {})
  define_getter_method(attr, options) do
    return params_root[attr] unless options[:deserializer]

    params_root[attr].map do |relation|
      options[:deserializer].new(relation).deserialize
    end if params_root[attr].is_a?(Array)
  end
end

ignore(*param_names) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 127
def ignore(*param_names)
  param_names.each do |param_name|
    attrs << Attribute.new(param_name, ignored: true)
  end
end

include_root_key?() click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 154
def include_root_key?
  @root_key && !@discard_root_key
end

inherited(subclass) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 105
def inherited(subclass)
  subclass.instance_variable_set(:@attrs, @attrs)
  subclass.instance_variable_set(:@discard_root_key, @discard_root_key)
  subclass.instance_variable_set(:@key_format, @key_format)
  subclass.instance_variable_set(:@root_key, @root_key)
  subclass.instance_variable_set(:@strict_mode, @strict_mode)
end

root(key, options = {}) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 149
def root(key, options = {})
  @root_key = key
  @discard_root_key = options[:discard]
end

Public Instance Methods

deserialize() click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 43
def deserialize
  deserialized_params = {}
  self.class.attrs.unignored.each do |attr|
    next unless instance_exec(&attr.present_if)
    deserialized_params[attr.name] = self.send(attr.name)
  end
  format_keys(deserialized_params).with_indifferent_access
end

Private Instance Methods

format_key(key) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 56
def format_key(key)
  case self.class.key_format
  when :snake_case then key.to_s.underscore.to_sym
  when :camel_case then key.to_s.camelize.to_sym
  when :lower_camel then key.to_s.camelize(:lower).to_sym
  else key
  end
end

format_keys(hash) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 65
def format_keys(hash)
  hash = Hash[hash.map { |k, v| [format_key(k), v] }] if self.class.key_format
  optionally_include_root_key(hash)
end

optionally_include_root_key(hash) click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 70
def optionally_include_root_key(hash)
  return hash unless self.class.include_root_key?
  { format_key(self.class.root_key) => hash }
end

params_root() click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 75
def params_root
  return @params_root if @params_root

  if self.class.root_key
    @params_root = params[self.class.root_key]
  else
    @params_root = params
  end
end

verify_root_key_exists() click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 85
def verify_root_key_exists
  if self.class.root_key && !params.has_key?(self.class.root_key)
    raise MissingRootKeyError, "Root key #{self.class.root_key} is missing from params."
  end
end

verify_valid_keys() click to toggle source

# File lib/params_deserializers/params_deserializer.rb, line 91
def verify_valid_keys
  invalid_params = params_root.symbolize_keys.keys - self.class.attrs.map(&:original_name)
  if self.class.strict_mode && !invalid_params.empty?
    raise InvalidKeyError, "Invalid keys in params: #{invalid_params.map(&:inspect).join(",")}."
  end
end