pyjsonpatch

About

A Python implementation of JSON Pointer (RFC 6902) and JSON Patch (RFC 6902). Primarily, the package can do the following to Python object(s) representing JSON(s):

• apply_patch to modify an object with a JSON patch
• generate_patch to generate a JSON Patch from two objects
• get_by_ptr to retrieve a value from object using a JSON pointer

Table of Contents

• About
• Table of Contents
• Installation
• Development
  • Linting and Formatting
  • Building and Releasing
• Examples
  • get_by_ptr
  • apply_patch
  • generate_patch

Installation

Python 3.8 or higher is required. You can install the library with:

# Linux/macOS
python3 -m pip install -U pyjsonpatch

# Windows
py -3 -m pip install -U pyjsonpatch

Development

Install the dev requirements with:

# Linux/macOS
python3 -m pip install -r requirements-dev.txt

# Windows
py -3 -m pip install -r requirements-dev.txt

Linting and Formatting

Run the Ruff linter and formatter with:

# Lint
ruff check --fix

# Format
ruff format

Testing

Run tests with:

# Linux/macOS
python3 -m unittest discover tests

# Windows
py -3 -m unittest discover tests

Building and Releasing

Build with:

# Linux/macOS
python3 -m build

# Windows
py -3 -m build

Commit messages should follow Conventional Commits and version numbers follow Semantic Versioning. Releases require a version bump in pyproject.toml alongside a push to main with that version as a tag.

Examples

get_by_ptr

from pyjsonpatch import get_by_ptr


source = {"": 1, "foo": [2, 3]}

print(get_by_ptr(source, "").obj)
# {"": 1, "foo": [2, 3]}
print(get_by_ptr(source, "/").obj)
# 1
print(get_by_ptr(source, "/foo").obj)
# [2, 3]
print(get_by_ptr(source, "/foo/0").obj)
# 2

apply_patch

from pyjsonpatch import apply_patch


source = {"": 1, "foo": [2, 3]}
patch = [
  {"op": "add", "path": "/hello", "value": "world"},
  {"op": "add", "path": "/foo/1", "value": 4},
  {"op": "add", "path": "/foo/-", "value": 5},
  {"op": "remove", "path": "/"},
]
res = apply_patch(source, patch)

print(res.obj)
# {"foo": [2, 4, 3, 5], "hello": "world"}
print(res.obj is source)
# True
#  - source was mutated
print(res.removed)
# [None, None, None, 1]
#  - Only the 4th operation removes something

generate_patch

from pyjsonpatch import generate_patch


source = {"": 1, "foo": [2, 3]}
target = {"foo": [2, 4], "hello": "world"}
print(generate_patch(source, target))
# [
#   {"op": "remove": "path": "/"},
#   {"op": "replace": "path": "/foo/1", "value": 4},
#   {"op": "add": "path": "/hello", "value": "world"},
# ]