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# Hack to load json gem first so we can overwrite its to_json.
require 'json'
require 'bigdecimal'
require 'active_support/core_ext/big_decimal/conversions' # for #to_s
require 'active_support/core_ext/hash/except'
require 'active_support/core_ext/hash/slice'
require 'active_support/core_ext/object/instance_variables'
require 'time'
require 'active_support/core_ext/time/conversions'
require 'active_support/core_ext/date_time/conversions'
require 'active_support/core_ext/date/conversions'
require 'active_support/core_ext/module/aliasing'
# The JSON gem adds a few modules to Ruby core classes containing :to_json definition, overwriting
# their default behavior. That said, we need to define the basic to_json method in all of them,
# otherwise they will always use to_json gem implementation, which is backwards incompatible in
# several cases (for instance, the JSON implementation for Hash does not work) with inheritance
# and consequently classes as ActiveSupport::OrderedHash cannot be serialized to json.
#
# On the other hand, we should avoid conflict with ::JSON.{generate,dump}(obj). Unfortunately, the
# JSON gem's encoder relies on its own to_json implementation to encode objects. Since it always
# passes a ::JSON::State object as the only argument to to_json, we can detect that and forward the
# calls to the original to_json method.
#
# It should be noted that when using ::JSON.{generate,dump} directly, ActiveSupport's encoder is
# bypassed completely. This means that as_json won't be invoked and the JSON gem will simply
# ignore any options it does not natively understand. This also means that ::JSON.{generate,dump}
# should give exactly the same results with or without active support.
[Object, Array, FalseClass, Float, Hash, Integer, NilClass, String, TrueClass, Enumerable].each do |klass|
klass.class_eval do
def to_json_with_active_support_encoder(options = nil)
if options.is_a?(::JSON::State)
# Called from JSON.{generate,dump}, forward it to JSON gem's to_json
self.to_json_without_active_support_encoder(options)
else
# to_json is being invoked directly, use ActiveSupport's encoder
ActiveSupport::JSON.encode(self, options)
end
end
alias_method_chain :to_json, :active_support_encoder
end
end
class Object
def as_json(options = nil) #:nodoc:
if respond_to?(:to_hash)
to_hash.as_json(options)
else
instance_values.as_json(options)
end
end
end
class Struct #:nodoc:
def as_json(options = nil)
Hash[members.zip(values)].as_json(options)
end
end
class TrueClass
def as_json(options = nil) #:nodoc:
self
end
end
class FalseClass
def as_json(options = nil) #:nodoc:
self
end
end
class NilClass
def as_json(options = nil) #:nodoc:
self
end
end
class String
def as_json(options = nil) #:nodoc:
self
end
end
class Symbol
def as_json(options = nil) #:nodoc:
to_s
end
end
class Numeric
def as_json(options = nil) #:nodoc:
self
end
end
class Float
# Encoding Infinity or NaN to JSON should return "null". The default returns
# "Infinity" or "NaN" which are not valid JSON.
def as_json(options = nil) #:nodoc:
finite? ? self : nil
end
end
class BigDecimal
# A BigDecimal would be naturally represented as a JSON number. Most libraries,
# however, parse non-integer JSON numbers directly as floats. Clients using
# those libraries would get in general a wrong number and no way to recover
# other than manually inspecting the string with the JSON code itself.
#
# That's why a JSON string is returned. The JSON literal is not numeric, but
# if the other end knows by contract that the data is supposed to be a
# BigDecimal, it still has the chance to post-process the string and get the
# real value.
def as_json(options = nil) #:nodoc:
finite? ? to_s : nil
end
end
class Regexp
def as_json(options = nil) #:nodoc:
to_s
end
end
module Enumerable
def as_json(options = nil) #:nodoc:
to_a.as_json(options)
end
end
class Range
def as_json(options = nil) #:nodoc:
to_s
end
end
class Array
def as_json(options = nil) #:nodoc:
map { |v| options ? v.as_json(options.dup) : v.as_json }
end
end
class Hash
def as_json(options = nil) #:nodoc:
# create a subset of the hash by applying :only or :except
subset = if options
if attrs = options[:only]
slice(*Array(attrs))
elsif attrs = options[:except]
except(*Array(attrs))
else
self
end
else
self
end
Hash[subset.map { |k, v| [k.to_s, options ? v.as_json(options.dup) : v.as_json] }]
end
end
class Time
def as_json(options = nil) #:nodoc:
if ActiveSupport.use_standard_json_time_format
xmlschema(ActiveSupport::JSON::Encoding.time_precision)
else
%(#{strftime("%Y/%m/%d %H:%M:%S")} #{formatted_offset(false)})
end
end
end
class Date
def as_json(options = nil) #:nodoc:
if ActiveSupport.use_standard_json_time_format
strftime("%Y-%m-%d")
else
strftime("%Y/%m/%d")
end
end
end
class DateTime
def as_json(options = nil) #:nodoc:
if ActiveSupport.use_standard_json_time_format
xmlschema(ActiveSupport::JSON::Encoding.time_precision)
else
strftime('%Y/%m/%d %H:%M:%S %z')
end
end
end
class Process::Status #:nodoc:
def as_json(options = nil)
{ :exitstatus => exitstatus, :pid => pid }
end
end
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