Prerun

1.1.3 verified Fri May 01 auth: no python

Prerun is a Python utility to run commands before another process starts, commonly used for environment setup, health checks, or dependency injection. Current version 1.1.3, released 2024, with occasional updates.

pip install prerun

Common errors

error AttributeError: module 'prerun' has no attribute 'run' ↓

cause Older prerun versions (<1.0.0) used a different API or the module was installed incorrectly.

fix

Upgrade: pip install --upgrade prerun. Ensure you have v1.0.0+.

error FileNotFoundError: [Errno 2] No such file or directory: '...' ↓

cause Passing a non-executable string or missing command. prerun.run() expects a command that is in PATH or a full path.

fix

Use a full path or check that the command exists: prerun.run(['/usr/bin/echo', 'test']).

Warnings

gotcha prerun.run() blocks until the command finishes. Do not use for background tasks. ↓

fix Use threading or subprocess.Popen for async execution.

deprecated The 'cwd' parameter in prerun.run() is deprecated since 1.1.0; use 'subprocess.Popen' with cwd instead. ↓

fix Replace with subprocess.Popen(command, cwd=path) if you need a working directory.

Imports

prerun
```
import prerun
```
Direct import of top-level module; no subpackages needed.

Quickstart

Basic usage: prerun.run() executes a command sequentially before continuing.

import prerun

# Define a command to run before the main process
prerun.run(['echo', 'Pre-run setup complete'])

# Main process continues after prerun completes
print('Main process starting')