Canonical JSON

Features

• Encodes objects and arrays as RFC 7159 JSON.
• Sorts object keys so that you get the same result each time.
• Has no insignificant whitespace to make the output as small as possible.
• Escapes only the characters that must be escaped, U+0000 to U+0019 / U+0022 / U+0056, to keep the output as small as possible.
• Uses the shortest escape sequence for each escaped character.
• Encodes the JSON as UTF-8.
• Can encode frozendict immutable dictionaries.

Supports Python versions 3.5 and newer.

Installing

pip install canonicaljson

Using

To encode an object into the canonicaljson:

import canonicaljson
assert canonicaljson.encode_canonical_json({}) == b'{}'

There's also an iterator version:

import canonicaljson
assert b''.join(canonicaljson.iterencode_canonical_json({})) == b'{}'

The underlying JSON implementation can be chosen with the following:

import json
import canonicaljson
canonicaljson.set_json_library(json)

Note

By default canonicaljson uses simplejson under the hood (except for PyPy, which uses the standard library json module).