ruby - 从线程循环中脱离出来

Question

我正在从(降序)按时间排序的画廊下载图像。我想停下来，当我们看到已经放下的照片时。

require 'thread/pool'

def getimg(uri)
#...
  if File.exist? filename
    raise "Already done."  # something like this
  end
#...
end

pool = Thread.pool(4)

thumbs.each do |a|
  pool.process {
    getimg(URI(a.attr('href')))
  }
end

Answer 1

如何传递一个池对象并使用 pool.shutdown？

require 'thread/pool'

def getimg(uri, pool) # <----
#...
  if File.exist? filename
    pool.shutdown  # <--------
    return         # <------
  end
#...
end

pool = Thread.pool(4)

thumbs.each do |a|
  pool.process {
    getimg(URI(a.attr('href')), pool) # <----
  }
end

根据 the Thread::Pool#process code comment :

Shut down the pool, it will block until all tasks have finished running.

更新

使用 shutdown! 而不是 shutdown。

shutown! Shut down the pool instantly without finishing to execute tasks.