Checking Minimagick height freezes console

问题:

I'm using Rails with MiniMagick and have this obj that I've uploaded through file_field and MiniMagick::Image.read(image.read):

=> #<MiniMagick::Image:0x007feb61ac7048
 @info=#<MiniMagick::Image::Info:0x007feb61ac6ff8 @info={}, @path="/var/folders/s5/0r70nfzn2cj74qmc90ry3kc80000gp/T/mini_magick20170608-62480-1kxoub0">,
 @path="/var/folders/s5/0r70nfzn2cj74qmc90ry3kc80000gp/T/mini_magick20170608-62480-1kxoub0",
 @tempfile=#<File:/var/folders/s5/0r70nfzn2cj74qmc90ry3kc80000gp/T/mini_magick20170608-62480-1kxoub0 (closed)>>

I want to look into the object's height with image['height'] but whenever I've done that my command line freezes or I get No live threads left. Deadlock?. If I just let the program run without the debugger I get

`identify -format %m %w %h %b /var/folders/s5/0r70nfzn2cj74qmc90ry3kc80000gp/T/mini_magick20170608-62480-v5agnm[0]` failed with error: identify: no decode delegate for this image format `' @ error/constitute.c/ReadImage/509.

I've tried adding in

MiniMagick.configure do |config|
  config.validate_on_create = false
  config.validate_on_write = false
end

But it hasn't helped.

回答1:

I think the problem is in your image path, For troubleshooting take RMagick out of the equation and just test find the file with:

myfile = "#{RAILS_ROOT}/public/images/world.jpg"
  File.open myfile, 'r' { |f| puts "Success!\n\nFile Contents:" + f.read
}

Also, try using "script/console" to play with this. The above lines can be typed in there. It will make it easier to experiment without crashing the web server.

for your reference