《Git Pro 2》学习笔记_Chapter 10_Object Storage

用一段Ruby段码说明Git是如何存储三种类型的对象的：blob、tree、commit

$ irb
>> content = "what is up, doc?"
=> "what is up, doc?"
>>header = "blob #{content.length}\0"
=>"blob 16\u0000"
>>store = header + content
=>"blob 16\u0000what is up, doc?"
>>require 'digest/sha1'
=>true
>>sha1 = Digest::SHA1.hexdigest(store)
=>"bd9dbf5aae1a3862dd1526723246b20206e5fc37"
>>require 'zlib'
=>true
>>zlib_content = Zlib::Deflate.deflate(store)
=>"x\x9CK\xCA\xC9OR04c(\xCFH,Q\xC8,V(-\xD0QH\xC9O\xB6\a\x00_\x1C\a\x9D"
>>path = '.git/objects/' + sha1[0,2] + '/' + sha1[2,38]
=>".git/objects/bd/9dbf5aae1a3862dd1526723246b20206e5fc37"
>>require 'fileutils'
=>true
>>FileUtils.mkdir_p(File.dirname(path))
=>".git/objects/bd"
>>File.open(path, 'w') { |f| f.write zlib_content }
=>32