generating email address images or something which can't be easily scraped
I'm looking for a better Text-to-image solution for my Rails project to replace my current method which is generating a png using ImageMagick every time a new record is created or updated.
I want to prevent a mass scraping of data and abuse of email addresses provided. I'm wondering if there is an API to generate the text or use of javascript, or SVG, etc. Anything short of Flash.
I'm looking for a better solution than my current method:
def create_new_email_image
if email_changed?
path_to_images = '/images/emails'
puts "Connecting to AWS..."
config = YAML.load(File.open("#{RAILS_ROOT}/config/s3_credentials.yml"))[RAILS_ENV]
AWS::S3::Base.establish_connection!(
:access_key_id => config['access_key_id'],
:secret_access_key => config['secret_access_key']
)
puts "Finding S3 bucket..."
begin
bucket = AWS::S3::Bucket.find config['bucket_name']
rescue AWS::S3::NoSuchBucket
AWS::S3::Bucket.create config['bucket_name']
bucket = AWS::S3::Bucket.find config['bucket_name']
end
images_path = "#{RAILS_ROOT}/tmp/"
file_name = "#{id}.png"
#file_name = "5056.png"
file_path = images_path + "/"+ file_name
File.delete file_path if File.exists?开发者_StackOverflow社区 file_path
img = Magick::Image.new(400, 22) { self.background_color = 'transparent' }
img.format = 'PNG'
text = Magick::Draw.new
text.annotate(img, 0, 0, 1, 0, "#{email}") {
self.gravity = Magick::WestGravity
self.pointsize = 18
self.fill = '#000000'
self.kerning = -1
self.font_weight = Magick::BoldWeight
}
img.write file_path
if AWS::S3::S3Object.exists? file_name, bucket.name + path_to_images
puts "file exists (deleting)"
AWS::S3::S3Object.delete file_name, bucket.name + path_to_images, :force => true
end
AWS::S3::S3Object.store file_name,
File.open(file_path),
bucket.name + path_to_images,
:content_type => 'image/png',
:access => :public_read,
:reload => true
`rm #{file_path}`
end
end
Rails provides a mail_to helper.
mail_to "me@domain.com"
# => <a href="mailto:me@domain.com">me@domain.com</a>
mail_to "me@domain.com", "My email", :encode => "javascript"
# => <script type="text/javascript">eval(decodeURIComponent('%64%6f%63...%27%29%3b'))</script>
mail_to "me@domain.com", "My email", :encode => "hex"
# => <a href="mailto:%6d%65@%64%6f%6d%61%69%6e.%63%6f%6d">My email</a>
mail_to "me@domain.com", nil, :replace_at => "_at_", :replace_dot => "_dot_", :class => "email"
# => <a href="mailto:me@domain.com" class="email">me_at_domain_dot_com</a>
mail_to "me@domain.com", "My email", :cc => "ccaddress@domain.com",
:subject => "This is an example email"
# => <a href="mailto:me@domain.com?cc=ccaddress@domain.com&subject=This%20is%20an%20example%20email">My email</a>
The :encode => "hex"
or :encode => "javascript"
options are what you are looking for.
I've had the same problem. Here is my solution:
def text_to_image(text,options={})
return if text.blank?
filename=get_text_file_path(text)
unless File.exists?(filename)
gc = Magick::Draw.new
gc.fill = options[:color] unless options[:color].blank?
gc.pointsize options[:size] unless options[:size].blank?
gc.font=options[:font] unless options[:font].blank?
gc.gravity = Magick::CenterGravity
gc.text(0,0, text)
metrics=gc.get_type_metrics(text)
image = Magick::Image.new(metrics.width, metrics.height){
self.background_color = 'transparent'
}
gc.draw(image)
image.write(filename)
end
end
I use after_save
callback to update graphic cache of email attribute.
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