simonqian · April 14, 2017 09:15 · Apr 14, 2017
diff --git a/base64_to_file.rb b/base64_to_file.rb
@@ -0,0 +1,28 @@
+module Base64ToFile
+  extend ActiveSupport::Concern
+
+  def base64_to_file(base64_data, filename=nil)
+    return base64_data unless base64_data.is_a? String
+
+    start_regex = /data:image\/[a-z]{3,4};base64,/
+    filename ||= SecureRandom.hex
+
+    regex_result = start_regex.match(base64_data)
+    if base64_data && regex_result
+      start = regex_result.to_s
+      tempfile = Tempfile.new(filename)
+      tempfile.binmode
+      tempfile.write(Base64.decode64(base64_data[start.length..-1]))
+      uploaded_file = ActionDispatch::Http::UploadedFile.new(
+        :tempfile => tempfile,
+        :filename => "#{filename}.jpg",
+        :original_filename => "#{filename}.jpg"
+      )
+
+      uploaded_file
+    else
+      nil
+    end
+  end
+
+end