escaping double quotes doesn't seem to work (invalid json response?)

[sanderhahn]

From the json spec:

char
any-Unicode-character-
except-"-or--or-
control-character
"

/
\b
\f
\n
\r
\t
\u four-hex-digits

[pkoch]

Can't really tell what's the problem. How can one reproduce this issue?

[sanderhahn]

# views/home/test.json.json_builder
valid_escapes "\"\\\/\b\f\n\r\t"

-- result in:

JSON::ParserError in Home#test
Showing /work/json_builder_error/JsonBuilderError/app/views/home/test.json.json_builder where line #2 raised:
756: unexpected token at '{"valid_escapes": ""/�\f\n\r\t"}'

vendor/bundle/gems/json-1.6.6/lib/json/common.rb:148:in parse' vendor/bundle/gems/json-1.6.6/lib/json/common.rb:148:inparse'
vendor/bundle/gems/json-1.6.6/lib/json/common.rb:13:in []' vendor/bundle/gems/json_builder-3.1.2/lib/json_builder/compiler.rb:147:inpretty_print'
vendor/bundle/gems/json_builder-3.1.2/lib/json_builder/compiler.rb:137:in include_callback' vendor/bundle/gems/json_builder-3.1.2/lib/json_builder/compiler.rb:117:infinalize'
vendor/bundle/gems/json_builder-3.1.2/lib/json_builder/compiler.rb:17:in generate' vendor/bundle/gems/actionpack-3.2.3/lib/action_view/template.rb:143:inblock in render'
vendor/bundle/gems/activesupport-3.2.3/lib/active_support/notifications.rb:125:in instrument' vendor/bundle/gems/actionpack-3.2.3/lib/action_view/template.rb:141:inrender'

[rickygu]

I got the same error. does json builder sanitize the output by escaping all json escape characters?

[sanderhahn]

The error occurs because the invalid json is parsed for pretty printing on development. Think that the json_escape method is incomplete. Was in a hurry for a deadline and switched to the jbuilder library instead.

# extensions.rb

  def json_escape
    self.gsub(/\n/, '\\n').
         gsub(/\r/, '\\r').
         gsub(/\t/, '\\t').
         gsub(/\f/, '\\f')
  end

Another design would be to make the DSL build into associative arrays and use existing libraries to encode to json (with or without pretty printing).

[jkloian]

Adding:

gsub(/"/, '"')

to the gsubs happening in extensions solves the problem. We put the following monkey patch in production until this is fixed:

require 'json_builder'

class String

private

json_escape = instance_method(:json_escape)

define_method :json_escape do
json_escape.bind(self).call.gsub(/"/, '"')
end

end

[dewski]

This has since been fixed and updated with how Rails handles encoding in JSON.

@sanderhahn The gem is responsible for handling encoding internally to optimize for speed, other external libraries tend to be bloated and do more than is needed for this case.