shil 2023.7.18.23.20

Shell helper utilities for python

shil
	Shell-util library for python. Includes helpers for subprocess invocation, shell-formatters / pretty-printers, and more.

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• Overview
  • Features
• Installation
• Usage
  • OOP-style Dispatch
  • Functional approach to dispatch
  • Loading data when command-output is JSON
  • Serialization with Pydantic
  • Caller determines logging
  • Rich-console Support
  • Stay DRY with Runners

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Overview

The shil library provides various shell-utilities for python.

Features

• Helpers for subprocess invocation
• Shell-formatters / pretty-printers
• A somewhat usable parser / grammer for bash
• Console support for rich & rich protocols

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Installation

See pypi for available releases.

pip install shil

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Usage

See also:

• the unit-tests for some examples of library usage
• the smoke-tests for example usage of stand-alone scripts

OOP-style Dispatch

This uses shil.Invocation and returns shil.InvocationResponse.

import shil 
req = cmd = shil.Invocation(command='ls /tmp')
resp = cmd()
print(resp.stdout)

Functional approach to dispatch

Use shil.invoke, get back shil.InvocationResponse

import shil 
resp = shil.invoke('ls /tmp')

Loading data when command-output is JSON

import shil 
req = cmd = shil.Invocation(command='echo {"foo":"bar"}')
resp = cmd()
print(resp.data)
assert type(resp.data) == type({})
assert resp.data['foo']=='bar'

Serialization with Pydantic

import shil 
import json
req = cmd = shil.Invocation(command='echo {"foo":"bar"}')
resp = cmd()
json.loads(resp.json())
json.loads(req.json())
for k,v in req.dict().items():
  assert getattr(resp,k)==v

Caller determines logging

Works like this with basic logger:

import shil 
import logging
logger = logging.getLogger()
shil.invoke('ls /tmp', command_logger=logger.critical, output_logger=logger.warning)

Supports using rich-logger too:

import shil 
from rich.console import Console 
console = Console(stderr=True)
shil.invoke('ls /tmp', command_logger=console.log)

Rich-console Support

Besides using rich-logger as above, you can use the rich-protocol more directly. Printing works the way you'd expect for Invocation and InvocationResponse.

import shil 
req = cmd = shil.Invocation(command='echo {"foo":"bar"}')
resp = cmd()
import rich
rich.print(req)
rich.print(resp)

Stay DRY with Runners

Runner's are basically just partials on shil.invoke. It's simple but this can help reduce copying around repetitive configuration.

from rich.console import Console 
console=Console(stderr=True)
runner = shil.Runner(
  output_logger=console.log,
  command_logger=console.log)
runner('ls /tmp')