kubectl-diff-filter.rb

#!/usr/bin/env ruby

# diffをファイル単位で分割して処理
# 実質的な変更がlabels/app.kubernetes.io/instanceの削除のみの場合はスキップ
# Usage
#    kubectl diff -k . | ruby ./kubectl-diff-filter.rb
IGNORABLE = /\A[-+][ \t]*(generation:\s*|labels:\s*|app\.kubernetes\.io\/instance:.*)/
ignored_diffs = []
diffs = STDIN.read.split(/^diff /).reject(&:empty?)
diffs.each do |diff|
  diff = "diff " + diff
  changed_lines = diff.lines.select { |l| l.match?(/\A[-+]/) && !l.match?(/\A[-+]{3} /) }
  if changed_lines.all? { |l| l.match?(IGNORABLE) }
    ignored_diffs << changed_lines
    next
  end
  puts diff
end


puts "\n=== Ignored diff summary ==="
ignored_diffs.map { |lines| lines.join }.tally.each do |k, v|
  puts "== Ignored diff lines count: #{v} =="
  puts k
  puts ""
end

puts 'Filtered by https://gist.github.com/fukajun/ad0dc6e4368b4c8c37089fc81f7e8139'