如何获得wget在ruby中的输出？

Question

I need to run the following code from ruby:

system "wget http://example.org/some/large/archive.zip"

When I run this command I see

Redirecting output to 'wget-log'.

I need to do tail -f wget-log to see the progress

How can I see wget output in terminal where I run the ruby process?

I've tried

system "wget -O - http://example.org/some/large/archive.zip > dev/null"

but it didn't help

Maybe there are other options to download large archives with ruby and see the progress?

Answer 1

You could use the Open3 module, which is in the Ruby's standard library.

This grants you access to stdout, stderr, exit codes and a thread to wait for the child process when running another program .

So, having a pwd command you can do something like:

require 'open3'
stdout, stderr, status = Open3.capture3('pwd')
puts stdout # ~/ current directory
puts stderr #    no error
puts status # pid 25522 exit 0

Answer 2

The ruby provide a good built-in libs to make any kind of http things, for example to download file you can use net/http :

require 'net/http'
require 'uri'

uri = URI(URI.encode("http://example.org/some/large/archive.zip"))
Net::HTTP.start(uri.host,uri.port) do |http|
  request = Net::HTTP::Get.new uri.path

  http.request request do |response|
    open "/tmp/my_large_file.zip", 'w' do |io|
       response.read_body do |chunk|
         puts "Writing  #{chunk.length} bits ..." # see progress
         io.write chunk
       end
     end
  end  
end

With wget you unable to catch any kind of http errors in your ruby code.*

With wget you unable to make auth, basic for example in your ruby code.*

Use Ruby built-in libs, it is very powerfull.

_{You able but with some buggy code}