refer: https://dannyda.com/2020/01/20/useful-curl-tips-download-upload-post-proxy-header-download-in-chunks-etc/#section1
使用--output就可保存图片(文件)了
curl www.bing.com --output bing.htm
使用proxy保存图到本地:
command_get_image = %Q{curl -s --socks5 #{proxy.ip}:#{proxy.port} #{image_src} --output public/blog_images/#{image_name}}