unneeded_dependencies.rb

#! /usr/bin/env ruby

require "json"
require "set"
require "yaml"

USAGE = <<-EOS

USAGE: From within an application folder that includes Packwerk packages, run this
script. The script will loop through each package.yml and check each of the declared
dependencies to find any that are no longer needed.

This takes a bit ⏳

EOS

options = ARGV.shift
if options == "-h" || options == "--help"
  puts USAGE
  exit
end

file_pattern = "**/package.yml"
services = Dir.glob("./**/package.yml").filter do |f|
   f =~ /\.\/services/
end

def check(output)
  system('bundle exec packwerk check', out: output)
end

def clean_name(name)
  name.sub("./", "").sub("/package.yml", "")
end

if !check(File::NULL)
  puts "💥 Packweck check fails on this branch"
  exit
end

data = Set.new

start = Time.now
services.sort.each do |file|
  name = clean_name(file)

  contents = {}
  begin
    contents = YAML.load_file(file)
  rescue
    next
  end

  next unless contents['enforce_dependencies'] && contents['dependencies']

  contents['dependencies'].each do |dependency|
    data.add([name, dependency].join("|"))
  end

  # clear deps
  contents['dependencies'] = []
  File.open(file, 'w') do |f|
    f.write contents.to_yaml
  end
end

violation_file = "/tmp/violations"
File.open(violation_file, "w") do |f|
  check(f)
end

violations = File.readlines(violation_file).select { |line| line =~ /\ADependency violation/ }

violations.each do |violation|
  pieces = /but '(.+?)' does not specify a dependency on '(.+?)'/.match(violation)
  data.delete([pieces[1], pieces[2]].join("|"))
end

system("git checkout .", out: File::NULL)
puts

puts
puts "Done in #{Time.now - start}s"
puts

puts "Summary: "
if data.count == 0
  puts "No unnecessary dependencies"
else
  data.to_a.each do |violation|
    pieces = violation.split('|')
    puts pieces.join(" →\t")
  end
end