debx 0.1.4

Minimal Python library to programmatically construct Debian .deb packages

debx

A lightweight Python library for creating, reading, and manipulating Debian package (.deb) files.

Features

• Read and extract content from Debian packages
• Create custom Debian packages programmatically
• Parse and manipulate Debian control files (RFC822-style format)
• Low-level AR archive manipulation
• No external dependencies - uses only Python standard library
• Command-line interface for creating and unpacking .deb packages

Installation

pip install debx

Quick Start

Reading a Debian Package

from debx import DebReader

# Open a .deb file
with open("package.deb", "rb") as f:
    reader = DebReader(f)

    # Extract control file
    control_file = reader.control.extractfile("control")
    control_content = control_file.read().decode("utf-8")
    print(control_content)
    
    # List files in the data archive
    print(reader.data.getnames())
    
    # Extract a file from the data archive
    file_data = reader.data.extractfile("usr/bin/example").read()

Creating a Debian Package

from debx import DebBuilder, Deb822

# Initialize the builder
builder = DebBuilder()

# Create control information
control = Deb822({
    "Package": "example",
    "Version": "1.0.0",
    "Architecture": "all",
    "Maintainer": "Example Maintainer <[e-mail]>",
    "Description": "Example package\n This is an example package created with debx.",
    "Section": "utils",
    "Priority": "optional"
})

# Add control file
builder.add_control_entry("control", control.dump())

# Add files to the package
builder.add_data_entry(b"#!/bin/sh\necho 'Hello, world!'\n", "/usr/bin/example", mode=0o755)

# Add a symlink
builder.add_data_entry(b"", "/usr/bin/example-link", symlink_to="/usr/bin/example")

# Build the package
with open("example.deb", "wb") as f:
    f.write(builder.pack())

Working with Debian Control Files

from debx import Deb822

# Parse a control file
control = Deb822.parse("""
Package: example
Version: 1.0.0
Description: Example package
 This is a multi-line description
 with several paragraphs.
""")

print(control["Package"])  # "example"
print(control["Description"])  # Contains the full multi-line description

# Modify a field
control["Version"] = "1.0.1"

# Add a new field
control["Priority"] = "optional"

# Write back to string
print(control.dump())

Command-Line Interface

debx includes a command-line interface for packing and unpacking Debian packages.

Packing a Debian Package

The pack command allows you to create a .deb package from files on your system:

debx pack \
    --control control:control \
              preinst:preinst:mode=0755 \
    --data src/binary:/usr/bin/example:mode=0755 \
           src/config:/etc/example/config \
           src/directory:/opt/example \
    --output example.deb

The format for specifying files is:

source_path:destination_path[:modifiers]

Available modifiers:

• mode=0755 - Set file permissions
• uid=1000 - Set file owner ID
• gid=1000 - Set file group ID
• mtime=1234567890 - Set file modification time

When specifying a directory, all files within that directory will be included in the package while preserving the directory structure.

Unpacking a Debian Package

The unpack command extracts a .deb package into a directory:

debx unpack package.deb --directory output_dir

This will extract the internal AR archive members (debian-binary, control.tar.gz, data.tar.*) to the specified directory.

License

MIT License

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.