discourse/lib/file_helper.rb

50 lines
1.3 KiB
Ruby

require "open-uri"
class FileHelper
def self.is_image?(filename)
filename =~ images_regexp
end
def self.download(url, max_file_size, tmp_file_name, follow_redirect=false)
raise Discourse::InvalidParameters.new(:url) unless url =~ /^https?:\/\//
uri = parse_url(url)
extension = File.extname(uri.path)
tmp = Tempfile.new([tmp_file_name, extension])
File.open(tmp.path, "wb") do |f|
downloaded = uri.open("rb", read_timeout: 5, redirect: follow_redirect, allow_redirections: :all)
while f.size <= max_file_size && data = downloaded.read(512.kilobytes)
f.write(data)
end
# tiny files are StringIO, no close! on them
downloaded.try(:close!) rescue nil
end
tmp
end
private
def self.images
@@images ||= Set.new ["jpg", "jpeg", "png", "gif", "tif", "tiff", "bmp", "svg", "webp"]
end
def self.images_regexp
@@images_regexp ||= /\.(#{images.to_a.join("|")})$/i
end
# HACK to support underscores in URLs
# cf. http://stackoverflow.com/a/18938253/11983
def self.parse_url(url)
URI.parse(url)
rescue URI::InvalidURIError
host = url.match(".+\:\/\/([^\/]+)")[1]
uri = URI.parse(url.sub(host, 'valid-host'))
uri.instance_variable_set("@host", host)
uri
end
end