How to encode media in base64 given URL in Ruby
I'm trying to upload an image to PingFM. Their documentation says:
media – base64 encoded media data.
I can access this image via the URL. I tried (practically guessed) this:
ActiveSupport::Base64.encode64(open("http://image.com/img.jpg"))
But I get this error:
TypeError: can't convert Tempfile into String
from /usr/lib/ruby/1.8/base64.rb:97:in `pack'
from /usr/lib/rub开发者_JS百科y/1.8/base64.rb:97:in `encode64'
from (irb):19
from :0
To encode a file:
require 'base64'
Base64.encode64(File.open("file_path", "rb").read)
To produce the file from the encoded string:
require 'base64'
encoded_string = Base64.encode64(File.open("file_path", "rb").read)
File.open(file_name_to_create, "wb") do |file|
file.write(Base64.decode64(encoded_string))
end
The open
method:
open("http://image.com/img.jpg")
is returning a Tempfile object, while encode64
expects a String.
Calling read
on the tempfile should do the trick:
ActiveSupport::Base64.encode64(open("http://image.com/img.jpg") { |io| io.read })
This will work too, it's a little cleaner
require 'base64'
Base64.encode64(open("file_path").to_a.join)
"How do you decode this back into a file?" - @user94154
require 'base64'
open('output_file_name.txt', 'w') do |f|
f << Base64.decode64( encoded_content )
end
Where encoded_content
would be the previously encoded file content return value.
Encode a file to base64 encoding:
File.open("output_file","w"){|file| file.write [open("link_to_file").string].pack("m")}
Decode base64 encoded file:
File.open('original', 'wb') {|file| file << (IO.readlines('output_file').to_s.unpack('m')).first }
Here's my solution:
1: Put this custom image_tag method into ApplicationHelper, and include ActiveSupport module
module ApplicationHelper
include ActiveSupport
def image_tag_base64(file_path, mime_type = 'image/jpeg', options = {})
image_tag("data:#{mime_type};base64,#{Base64.encode64(open(file_path) { |io| io.read })}", options)
end
end
2: Then, inside the view you want to use base64 encoded image use the method like this:
<%= image_tag_base64 @model.paperclip_attribute.path(:size), @model.paperclip_attribute.content_type, {class: 'responsive-img etc etc'} %>
3: DONE
In case it's useful to others, here's how to save a screenshot as base64 using Watir
browser = Watir::Browser.new(:chrome, {:chromeOptions => {:args => ['--headless', '--window-size=1000x1000']}})
browser.goto("http://www.yourimage.com")
browser.screenshot.base64
The beauty of this is you don't need to store the image itself
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