在s3上设置Fog存储文件的content_type(Set content_type of Fog storage files on s3)

 我正在与Fog和Amazon s3合作管理视频和图像文件。 我为我的文件设置content_type时遇到了很多麻烦。 
 
 在从控制台工作时，我能够通过并单独更新每个文件的content_type，然后运行save。 但是，当我尝试对特定目录中的所有文件运行更新时，我没有收到错误，但没有任何更新。 我运行了多种不同的方法，都具有相同的基本思想，并且都设置为打印“已保存！” 如果文件保存。 方法运行正常并打印出“已保存！”，但当我返回并检查文件时，content_type仍为零。 
 
 这是我正在做的一个例子： 
 
directory.files.each do |f|
  case f.key.split(".").last
  when "jpg"
    f.content_type = "image/jpeg"
    puts "saved!" if f.save
  when "mov"
    f.content_type = "video/quicktime"
    puts "saved!" if f.save
  end
end
 
 此外，当我通过并单独更新每个文件时，保存工作和content_type得到更新，但数据不会持久。 
 
 例如： 
 
file = directory.files.first
file.content_type = 'video/quicktime'
file.save         # returns true
file.content_type # returns 'video/quicktime'
 
 但是，当我在AWS中检查文件时，内容类型仍为零。 
 
 是否有更好的（持久的）方法来更新Fog s3文件上的content_type？ 我觉得我必须以错误的方式解决这个问题。 
 
 更新：使用文件#copy方法尝试： 
 
directory.files.each do |f|
  content_type = case f.key.split(".").last
  when "jpg"
    "image/jpeg"
  when "mov"
    "video/quicktime"
  end
  puts "copied!" if f.copy(f.directory.key, f.key, { 'Content-Type' => content_type })
end
 
 我收到一个错误： 
 
Excon::Errors::BadRequest: Expected(200) <=> Actual(400 Bad Request)

from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/excon-0.22.1/lib/excon/middlewares/expects.rb:6:in `response_call'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/excon-0.22.1/lib/excon/connection.rb:355:in `response'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/excon-0.22.1/lib/excon/connection.rb:249:in `request'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/fog-1.11.1/lib/fog/core/connection.rb:21:in `request'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/fog-1.11.1/lib/fog/aws/storage.rb:506:in `request'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/fog-1.11.1/lib/fog/aws/requests/storage/copy_object.rb:33:in `copy_object'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/fog-1.11.1/lib/fog/aws/models/storage/file.rb:93:in `copy'
from (irb):14
from /Users/marybethlee/.rvm/rubies/ruby-2.0.0-p0/bin/irb:16:in `<main>'

I'm working with Fog and Amazon s3 to manage video and image files. I've been running into a lot of trouble with setting the content_type for my files.
 
When working from the console, I am able to go through and individually update each file's content_type, and then run save. However, when I try to run an update on all of the files within a specific directory, I don't get an error, but nothing gets updated. I've run multiple different methods, all with the same basic idea, and all set to print "saved!" if the file saves. The methods run properly and print out "saved!", but when I go back and check the files, the content_type is still nil.
 
Here's an example of what I'm doing:
 
directory.files.each do |f|
  case f.key.split(".").last
  when "jpg"
    f.content_type = "image/jpeg"
    puts "saved!" if f.save
  when "mov"
    f.content_type = "video/quicktime"
    puts "saved!" if f.save
  end
end
 
Also, when I go through and individually update each file, the save works and the content_type gets updated, but the data doesn't persist.
 
For example:
 
file = directory.files.first
file.content_type = 'video/quicktime'
file.save         # returns true
file.content_type # returns 'video/quicktime'
 
However, when I go check the file in AWS, the content type is still nil. 
 
Is there a better (persistent) way of going about updating content_type on Fog s3 files? I feel like I must be going about this the wrong way.
 
Update: Tried using the file#copy method:
 
directory.files.each do |f|
  content_type = case f.key.split(".").last
  when "jpg"
    "image/jpeg"
  when "mov"
    "video/quicktime"
  end
  puts "copied!" if f.copy(f.directory.key, f.key, { 'Content-Type' => content_type })
end
 
I got an error:
 
Excon::Errors::BadRequest: Expected(200) <=> Actual(400 Bad Request)

from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/excon-0.22.1/lib/excon/middlewares/expects.rb:6:in `response_call'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/excon-0.22.1/lib/excon/connection.rb:355:in `response'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/excon-0.22.1/lib/excon/connection.rb:249:in `request'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/fog-1.11.1/lib/fog/core/connection.rb:21:in `request'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/fog-1.11.1/lib/fog/aws/storage.rb:506:in `request'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/fog-1.11.1/lib/fog/aws/requests/storage/copy_object.rb:33:in `copy_object'
from /Users/marybethlee/.rvm/gems/ruby-2.0.0-p0@mothership/gems/fog-1.11.1/lib/fog/aws/models/storage/file.rb:93:in `copy'
from (irb):14
from /Users/marybethlee/.rvm/rubies/ruby-2.0.0-p0/bin/irb:16:in `<main>'

原文：