Methods

Constants

DATETIME_REGEX = /\A(?:\d{4}-\d{2}-\d{2}|\d{4}-\d{1,2}-\d{1,2}[T \t]+\d{1,2}:\d{2}:\d{2}(\.[0-9]*)?(([ \t]*)Z|[-+]\d{2}?(:\d{2})?)?)\z/
DATE_REGEX = /\A\d{4}-\d{2}-\d{2}\z/
 

matches YAML-formatted dates

Attributes

[RW] escape_html_entities_in_json

If true, encode >, <, & as escaped unicode sequences (e.g. > as u003e) as a safety measure.
[RW] escape_js_separators_in_json

If true, encode LINE SEPARATOR (U+2028) and PARAGRAPH SEPARATOR (U+2029) as escaped unicode sequences (‘u2028’ and ‘u2029’). Historically these characters were not valid inside JavaScript strings but that changed in ECMAScript 2019. As such it’s no longer a concern in modern browsers: caniuse.com/mdn-javascript_builtins_json_json_superset.
[R] json_encoder

Sets the encoder used by Rails to encode Ruby objects into JSON strings in +Object#to_json+ and ActiveSupport::JSON.encode.
[RW] time_precision

Sets the precision of encoded time values. Defaults to 3 (equivalent to millisecond precision)
[RW] use_standard_json_time_format

If true, use ISO 8601 format for dates and times. Otherwise, fall back to the Active Support legacy format.

Class Public methods

decode(json, options = {})

Parses a JSON string (JavaScript Object Notation) into a Ruby object. See www.json.org for more info.

ActiveSupport::JSON.decode("{\"team\":\"rails\",\"players\":\"36\"}")
# => {"team" => "rails", "players" => "36"}
ActiveSupport::JSON.decode("2.39")
# => 2.39

Also aliased as: load.

📝 Source code 
# File activesupport/lib/active_support/json/decoding.rb, line 24
def decode(json, options = {})
  data = ::JSON.parse(json, options)

  if ActiveSupport.parse_json_times
    convert_dates_from(data)
  else
    data
  end
end
🔎 See on GitHub

dump(value, options = nil)

Alias for: encode.

encode(value, options = nil)

Dumps objects in JSON (JavaScript Object Notation). See www.json.org for more info.

ActiveSupport::JSON.encode({ team: 'rails', players: '36' })
# => "{\"team\":\"rails\",\"players\":\"36\"}"

By default, it generates JSON that is safe to include in JavaScript, as it escapes U+2028 (Line Separator) and U+2029 (Paragraph Separator):

ActiveSupport::JSON.encode({ key: "\u2028" })
# => "{\"key\":\"\\u2028\"}"

By default, it also generates JSON that is safe to include in HTML, as it escapes <, >, and &:

ActiveSupport::JSON.encode({ key: "<>&" })
# => "{\"key\":\"\\u003c\\u003e\\u0026\"}"

This behavior can be changed with the escape_html_entities option, or the global escape_html_entities_in_json configuration option.

ActiveSupport::JSON.encode({ key: "<>&" }, escape_html_entities: false)
# => "{\"key\":\"<>&\"}"

For performance reasons, you can set the escape option to false, which will skip all escaping:

ActiveSupport::JSON.encode({ key: "\u2028<>&" }, escape: false)
# => "{\"key\":\"\u2028<>&\"}"

Also aliased as: dump.

📝 Source code 
# File activesupport/lib/active_support/json/encoding.rb, line 47
def encode(value, options = nil)
  if options.nil? || options.empty?
    Encoding.encode_without_options(value)
  elsif options == { escape: false }.freeze
    Encoding.encode_without_escape(value)
  else
    Encoding.json_encoder.new(options).encode(value)
  end
end
🔎 See on GitHub

json_encoder=(encoder)

📝 Source code 
# File activesupport/lib/active_support/json/encoding.rb, line 229
def json_encoder=(encoder)
  @json_encoder = encoder
  @encoder_without_options = encoder.new
  @encoder_without_escape = encoder.new(escape: false)
end
🔎 See on GitHub

load(json, options = {})

Alias for: decode.

parse_error()

Returns the class of the error that will be raised when there is an error in decoding JSON. Using this method means you won’t directly depend on the ActiveSupport’s JSON implementation, in case it changes in the future.

begin
  obj = ActiveSupport::JSON.decode(some_string)
rescue ActiveSupport::JSON.parse_error
  Rails.logger.warn("Attempted to decode invalid JSON: #{some_string}")
end
📝 Source code 
# File activesupport/lib/active_support/json/decoding.rb, line 45
def parse_error
  ::JSON::ParserError
end
🔎 See on GitHub

Definition files