debx 0.2.1

Minimal Python library to programmatically construct Debian .deb packages

debx

Pronounced "deb-ex", debx is a Python library for creating, reading, and manipulating Debian package files. This pacage includes the debx command-line tool for packing and unpacking and inspecting any .deb packages.

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 and tar archives (debian-binary, control/, data/) into the specified directory.

Inspecting a Debian Package

The inspect command allows you to view the contents of a .deb package in different formats:

debx inspect package.deb  # --format=ls (default)

This will display the contents of the control file and the list of files in the data archive.

You can also specify the format to view the control file in different formats:

debx inspect --format=json package.deb 

See the --help option for more details on available formats.

License

MIT License

Contributing

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