Smile Data Format

"Smile" is a binary data format that defines a binary equivalent of standard JSON data format.

Format was specified in 2010 by Jackson JSON processor development team. First compliant implementation was included as a Jackson backend for Jackson version 1.6, released in September 2010.

Specification

Design documentation includes:

Smile Format Specification describes format itself; how it works and what a compliant parser/generator implementations needs to do.
Smile Format Design Goals explains rationale for design decisions concerning specification.

Community

Smile format Google group

Documentation

SmileFAQ
Smile Wikipedia entry
User documentation:
- Understanding Smile data format

Implementations

Smile Codecs

Clojure
- Cheshire library offers support via Jackson jackson-dataformat-smile
C
- libsmile is a small C-library for reading and writing Smile data.
Go
- go-smile Smile decoder written in Golang.
Java
- Jackson provides Smile support through jackson-dataformat-smile modules) format codec
  - Full support: including streaming access, data binding and tree model (100% parity with textual JSON)
  - Jackson 2.9 added "non-blocking" ((aka "asynchronous") decoding for JSON and Smile format backends
- Protostuff project supports Smile both as a low-level data format, and as format used for its RPC implementation
Javascript
- smile-js Smile decoder written in Javascript (only decodes (reads), does not encode (write))
Kotlin Multiplatform
- kotlinx-serialization-smile pure Kotlin Multiplatform implementation for kotlinx-serialization, supports JVM, Native, JS, etc
Python
- NewSmile Another Smile Format Decoder/Encoder for Python 3
- PySmile Python codec
Rust
- serde-smile Serde serializer and deserializer written in Rust.

Frameworks, Systems that use Smile codec (encoder and decoder)

Elastic Search uses Smile as transport format supports access using Smile encoding.
Apache Solr can use Smile as the response format with the wt=smile parameter.

Related Publications

Here are some external articles, blog posts, research papers that may be of interest: