Validates_captcha not generating a captcha

Newbie here.

This is not a question but a report on a work-around for a problem I
detected with the gem validates_captcha.

My environment is
Windows, Vista, Rails
Rails 2.3.5
Ruby 1.8.6
gem 1.3.5
validates_captcha-0.9.6

The problem:
validates_captcha is generating a default gif with the word “captcha” in
it rather than a captcha with the value of a a random string (the
captcha) in it.

The work-around:
In module .\lib\validates_captcha\image_generator\simple.rb there is the
following module


 def generate(captcha_code)
    image_width = captcha_code.length * 20 + 10

    cmd = []
    cmd << "convert -size #{image_width}x40 xc:grey84 -background

grey84 -fill black "

    captcha_code.split(//).each_with_index do |char, i|
      cmd << " -pointsize #{rand(8) + 15} "
      cmd << " -weight #{rand(2) == 0 ? '4' : '8'}00 "
      cmd << " -draw 'text #{5 + 20 * i},#{rand(10) + 20}

“#{char}”’ "
end

    cmd << "  -rotate #{rand(2) == 0 ? '-' : ''}5 -fill grey40 "

    captcha_code.size.times do
      cmd << "  -draw 'line #{rand(image_width)},0

#{rand(image_width)},60’ "
end

    cmd << "  gif:-"

    image_magick_command = cmd.join

    `#{image_magick_command}`
 end

The problem appears to be in the line
cmd << " gif:-"

replace this with
cmd << " gif:c:\tmp\SomeTempFile.gif"

and then read (binary) c:\tmp\SomeTempFile.gif and push that string out
instead of #{image_magick_command} pumping the output to stdout.

SomeTempFile.gif should probably not be a unique name since several
users might want to generate captchas at the same time. I keyed my name
off of the captcha code but there may be a better way to do this. If
anone has a good solution to this, I’d love to hear it.

Oh, do remember to delete the uniquely named file or your tmp directory
will fill up quickly.

It works for me. Your mileage may vary.

Ralph S. wrote:

Newbie here.

This is not a question but a report on a work-around for a problem I
detected with the gem validates_captcha.

When you are writing things like this, there is no need to begin your
posts with “Newbie here.”

Actually, that’s probably true in general. If your level of
understanding is that if a newbie, it will show in what you write. If
it doesn’t show in what you write (as here), then you’re not in newbie
territory. In either case, there is no point to beginning your posts
this way. :slight_smile:

Best,
–Â
Marnen Laibow-Koser
http://www.marnen.org
[email protected]