jmespath-extensions

JMESPath with 400+ extension functions for strings, arrays, dates, hashing, encoding, and more.

This package provides Python bindings for jmespath-extensions, a Rust library that extends JMESPath with hundreds of additional functions.

Installation

pip install jmespath-extensions

Quick Start

import jmespath_extensions as jpx

# String functions
jpx.search("upper(name)", {"name": "alice"})
# 'ALICE'

# Math functions
jpx.search("sum(values)", {"values": [1, 2, 3, 4, 5]})
# 15

jpx.search("median(scores)", {"scores": [10, 20, 30, 40, 50]})
# 30

# Date/time functions
jpx.search("format_date(now(), '%Y-%m-%d')", {})
# '2024-01-15'

# Array functions
jpx.search("unique(items)", {"items": [1, 2, 2, 3, 3, 3]})
# [1, 2, 3]

jpx.search("chunk(items, `2`)", {"items": [1, 2, 3, 4, 5, 6]})
# [[1, 2], [3, 4], [5, 6]]

# Object functions
jpx.search("pick(user, ['name', 'email'])", {"user": {"name": "alice", "email": "a@b.com", "age": 30}})
# {'name': 'alice', 'email': 'a@b.com'}

# Hash functions
jpx.search("md5(password)", {"password": "secret"})
# '5ebe2294ecd0e0f08eab7690d2a6ee69'

# Fuzzy matching
jpx.search("levenshtein(a, b)", {"a": "kitten", "b": "sitting"})
# 3

Compiled Expressions

For repeated searches, compile the expression once:

import jmespath_extensions as jpx

# Compile once
expr = jpx.compile("users[?age > `18`].name | sort(@)")

# Use many times
expr.search({"users": [{"name": "alice", "age": 30}, {"name": "bob", "age": 16}]})
# ['alice']

expr.search({"users": [{"name": "charlie", "age": 25}, {"name": "dave", "age": 19}]})
# ['charlie', 'dave']

Function Discovery

import jmespath_extensions as jpx

# List all categories
jpx.list_categories()
# ['standard', 'string', 'array', 'object', 'math', 'type', 'utility', ...]

# List functions in a category
jpx.list_functions("string")
# ['upper', 'lower', 'trim', 'split', 'replace', 'camel_case', ...]

# Get function details
jpx.describe("upper")
# {
#     'name': 'upper',
#     'category': 'string',
#     'description': 'Convert string to uppercase',
#     'signature': 'string -> string',
#     'example': "upper('hello') -> \"HELLO\"",
#     'is_standard': False
# }

Function Categories

See the full documentation for all 400+ functions.

Compatibility with jmespath-py

This package is designed to be a drop-in enhancement for jmespath. All standard JMESPath functions work exactly as expected:

import jmespath_extensions as jpx

# Standard JMESPath still works
jpx.search("length(items)", {"items": [1, 2, 3]})
# 3

jpx.search("sort(items)", {"items": [3, 1, 2]})
# [1, 2, 3]

jpx.search("[?age > `18`]", [{"age": 20}, {"age": 15}])
# [{'age': 20}]

Performance

This package uses Rust under the hood via PyO3, providing near-native performance for JSON processing.

License

MIT OR Apache-2.0