Get Debian-styled "depends" string for a self-compiled binary. A helper tool for `.deb` package builders.

get-depends-string.py

#!/usr/bin/env python3
#
# Get Debian-styled "depends" string for a self-compiled binary.
# A helper tool for `.deb` package builders.
#
# REQUIRES:
# - `apt-file` Debian package with recent database
#
# (c) 2023 Ratan M. Kyeno
# This code is licensed under MIT license, see https://opensource.org/license/mit/
import sys
import subprocess

# Get arguments slice past 1
args = sys.argv[1:]
if not args:
  print('Usage: ' + sys.argv[0] + ' /path/to/binary')
  sys.exit(1)

# Safe execution wrapper
def exec_or_die(cmd):
  result = subprocess.run([cmd], shell=True, capture_output=True, text=True)
  if result.returncode > 0 or not result.stdout or result.stdout == 'dynamic\n':
    print(f'Error executing: {cmd}')
    sys.exit(1)
  return result.stdout.strip()

# Iterate over raw dependencies and list packages
libs = exec_or_die("ldd " + ' '.join(args) + "$1|awk '{print $3}'|sed '/^[[:space:]]*$/d'|uniq -u|sort").split('\n')
packages = []
for lib in libs:
  print(lib, '... ', end='')

  # Support self-compiled libraries
  # ** L8R: DRY it up with exec_or_die() one day ;)
  cmd = f'apt-file search {lib}|head -1|cut -d " " -f 1|sed s/":"//g'
  result = subprocess.run([cmd], shell=True, capture_output=True, text=True)
  if result.returncode > 0:
    print(f'Error executing: {cmd}')
    sys.exit(1)
  elif not result.stdout:
    print('SELF COMPILED!')
  else:
    package = result.stdout.strip()
    print(package)
    packages.append(package)

# Uniquify packages
packages = list(dict.fromkeys(packages))
if not packages:
  print('There are no known dependencies to: ' + ''.join(args))
  sys.exit(0)

# Get package versions
depstring = ''
for index, package in enumerate(packages):

  # Test for currently installed version
  version = exec_or_die("dpkg-query -f '${Version}' -W '" + package + "'|cut -d '-' -f 1")

  # Append to dependency string
  depstring += package + ' (>=' + version + ')'
  if(index < len(packages) - 1):
    depstring += ', '

# Spit it out
print(f'Depends: {depstring}')