near-py-tool 0.1.20

Python NEAR contract build/deploy tool

Minimal build/deploy tool for Python NEAR smart contracts

This is a work-in-progress build/deploy tool for Python NEAR smart contracts.

Python source files are compiled into the WASM binary via MicroPython and Emscripten and then deployed via near-cli-rs tool.

near-py-tool CLI is modelled after cargo-near with most of the command-line options compatible (not all are implemented yet).

Dependencies

near-py-tool expects the following dependencies installed:

• Python>=3.9
• essential build tools like make and C compiler
• Emscripten for compiling Python into WASM via MicroPython
• near-cli-rs for NEAR Protocol interactions

Platform support

Currenly Linux (including WSL) and MacOS are supported with more platforms planned for the future.

Python library support

Most of the MicroPython standard library is included and should be functional where applicable to WASM runtime environment.

External Python package are supported as long as they don't require native compiled code to work. near-py-tool will download any packages referenced via pyproject.toml and will try to compile them into the WASM binary alongside the main contract.py file.

NEAR ABI support

Currenly a minimal version of NEAR WASM ABI is implemented via near module:

• near.input(index) retrieves the specified contract input as bytes
• near.value_return(value) returns a value (str or bytes) from the contract
• near.log_utf8(message) logs a message (str)

Contract methods to be exported from the WASM binary should be decorated with @near.export.

See the near-py-tool new-generated project for more details.

Getting started

• install near-py-tool via pip install near-py-tool
• run near-py-tool new test-project to create a minimal Python smart contract project
• cd ./test-project
• run near-py-tool build to produce a standalone WASM file
• run near-py-tool create-dev-account to create a testnet account if you don't have one already
• run near-py-tool deploy to deploy the smart contract

TODO

• Proper Python exception support (currently any thrown exception will log the exception message and terminate the contract execution)
• Tests and CI
• NEAR ABI metadata generation
• More platform support & automatic dependency installation