CertTool

A clean, modern, fully-typed Python CLI and library for generating self-signed X.509 certificates, certificate signing requests (CSRs), and private keys.

Built for automation, reproducibility, and bulk-generation workflows used by The Lupaxa Project.

Features

• Generate self-signed certificates, private keys, and CSRs
• Generate from:
  • JSON config file
  • Directory of config files (bulk mode)
  • Pure command-line flags
• Output:
  • To stdout
  • Or into an output directory, with one folder per certificate
• Supports:
  • RSA key generation
  • SHA-256 / SHA-384 / SHA-512 digests
  • Validity period configuration
  • Optional private key encryption with passphrase
  • Subject Alternative Names (SANs) via JSON or CLI
• Includes:
  • --generate-example to produce a full example JSON config
  • --inspect-cert to analyze existing PEM certificates
  • --validate-config to validate config files before use
• Fully typed, linted, formatted, and tested
• MkDocs documentation included

Installation

From PyPI

pip install lupaxa-certtool

From Source (Development Mode)

pip install -e ".[dev]"

Usage

Basic Self-Signed Certificate from CLI

certtool \
  --countryName UK \
  --stateOrProvinceName Somerset \
  --localityName Glastonbury \
  --organizationName "Lupaxa Project" \
  --commonName "dev.internal"

Using JSON Configuration

Generate an Example Config

certtool --generate-example --example-file dev-internal-cert.json

Use a JSON Config File

certtool --config dev-internal-cert.json

Use a Directory of Configs (Bulk Mode)

certtool --config-dir configs/

Output Directory Structure

If you pass:

certtool --config-dir configs/ --output-dir output/

You get:

output/
├── dev.internal/
│   ├── cert.pem
│   ├── csr.pem
│   └── key.pem
└── api.internal/
    ├── cert.pem
    ├── csr.pem
    └── key.pem

Each certificate gets its own folder to prevent overwriting.

Private Key Encryption

JSON

{
  "passphrase": "your-secret-here"
}

CLI (Overrides JSON)

certtool --config dev-internal-cert.json --passphrase "some-secret"

Inspect a Certificate

certtool --inspect-cert output/dev.interal/cert.pem

Development

Clone the repository and install dev dependencies:

pip install -e ".[dev]"

Useful make targets:

make test        # run tests
make type        # type checking (mypy)
make check-style # lint + format + type
make check-all   # run tests, coverage, and audit

Documentation

The published guide is at https://certtool.thelupaxaproject.org/.

Site Markdown lives in mkdocs/.

python -m pip install -r requirements.txt
make mkdocs-serve