gem¶ ↑

A fast JSON parser and Object marshaller as a Ruby gem.

Version 3.13 is out with a much faster parser (Oj::Parser) and option isolation.

Using¶ ↑

require 'oj'

h = { 'one' => 1, 'array' => [ true, false ] }
json = Oj.dump(h)

# json =
# {
#   "one":1,
#   "array":[
#     true,
#     false
#   ]
# }

h2 = Oj.load(json)
puts "Same? #{h == h2}"
# true

Installation¶ ↑

gem install oj

or in Bundler:

gem 'oj'

Rails and json quickstart¶ ↑

See the Quickstart sections of the Rails and json docs.

multi_json¶ ↑

Code which uses multi_json will automatically prefer Oj if it is installed.

Support¶ ↑

Get supported Oj with a Tidelift Subscription. Security updates are supported.

Further Reading¶ ↑

For more details on options, modes, advanced features, and more follow these links.

• {file:Options.md} for parse and dump options.

• {file:Modes.md} for details on modes for strict JSON compliance, mimicking the JSON gem, and mimicking Rails and ActiveSupport behavior.

• {file:JsonGem.md} includes more details on json gem compatibility and use.

• {file:Rails.md} includes more details on Rails and ActiveSupport compatibility and use.

• {file:Custom.md} includes more details on Custom mode.

• {file:Encoding.md} describes the :object encoding format.

• {file:Compatibility.md} lists current compatibility with Rubys and Rails.

• {file:Advanced.md} for fast parser and marshalling features.

• {file:Security.md} for security considerations.

• {file:InstallOptions.md} for install option.

Releases¶ ↑

See {file:CHANGELOG.md} and {file:RELEASE_NOTES.md}

Links¶ ↑

• Documentation: www.ohler.com/oj/doc, rubydoc.info/gems/oj

• GitHub repo: github.com/ohler55/oj

• RubyGems repo: rubygems.org/gems/oj

Follow @peterohler on Twitter for announcements and news about the Oj gem.

Performance Comparisons¶ ↑

• Oj Strict Mode Performance compares Oj strict mode parser performance to other JSON parsers.

• Oj Compat Mode Performance compares Oj compat mode parser performance to other JSON parsers.

• Oj Object Mode Performance compares Oj object mode parser performance to other marshallers.

• Oj Callback Performance compares Oj callback parser performance to other JSON parsers.

Links of Interest¶ ↑

• Fast XML parser and marshaller on RubyGems: rubygems.org/gems/ox

• Fast XML parser and marshaller on GitHub: github.com/ohler55/ox

• Need for Speed for an overview of how Oj::Doc was designed.

• OjC, a C JSON parser: www.ohler.com/ojc also at github.com/ohler55/ojc

• Agoo, a high performance Ruby web server supporting GraphQL on GitHub: github.com/ohler55/agoo

• Agoo-C, a high performance C web server supporting GraphQL on GitHub: github.com/ohler55/agoo-c

• oj-introspect, an example of creating an Oj parser extension in C: github.com/meinac/oj-introspect

Contributing¶ ↑

• Provide a Pull Request off the develop branch.

• Report a bug

• Suggest an idea

• Code is now formatted with the clang-format tool with the configuration file in the root of the repo.