Ruby DigestIO.wrap用法及代码示例

包装 io 并更新 digests Hash 中每个摘要算法的摘要。返回摘要哈希。例子：

io = StringIO.new
digests = {
  'SHA1'   => OpenSSL::Digest.new('SHA1'),
  'SHA512' => OpenSSL::Digest.new('SHA512'),
}

Gem::Package::DigestIO.wrap io, digests do |digest_io|
  digest_io.write "hello"
end

digests['SHA1'].hexdigest   #=> "aaf4c61d[...]"
digests['SHA512'].hexdigest #=> "9b71d224[...]"