114 lines
3.7 KiB
Ruby
114 lines
3.7 KiB
Ruby
# frozen_string_literal: true
|
|
|
|
# Gitlab::Middleware::Multipart - a Rack::Multipart replacement
|
|
#
|
|
# Rack::Multipart leaves behind tempfiles in /tmp and uses valuable Ruby
|
|
# process time to copy files around. This alternative solution uses
|
|
# gitlab-workhorse to clean up the tempfiles and puts the tempfiles in a
|
|
# location where copying should not be needed.
|
|
#
|
|
# When gitlab-workhorse finds files in a multipart MIME body it sends
|
|
# a signed message via a request header. This message lists the names of
|
|
# the multipart entries that gitlab-workhorse filtered out of the
|
|
# multipart structure and saved to tempfiles. Workhorse adds new entries
|
|
# in the multipart structure with paths to the tempfiles.
|
|
#
|
|
# The job of this Rack middleware is to detect and decode the message
|
|
# from workhorse. If present, it walks the Rack 'params' hash for the
|
|
# current request, opens the respective tempfiles, and inserts the open
|
|
# Ruby File objects in the params hash where Rack::Multipart would have
|
|
# put them. The goal is that application code deeper down can keep
|
|
# working the way it did with Rack::Multipart without changes.
|
|
#
|
|
# CAVEAT: the code that modifies the params hash is a bit complex. It is
|
|
# conceivable that certain Rack params structures will not be modified
|
|
# correctly. We are not aware of such bugs at this time though.
|
|
#
|
|
|
|
module Gitlab
|
|
module Middleware
|
|
class Multipart
|
|
RACK_ENV_KEY = 'HTTP_GITLAB_WORKHORSE_MULTIPART_FIELDS'.freeze
|
|
|
|
class Handler
|
|
def initialize(env, message)
|
|
@request = Rack::Request.new(env)
|
|
@rewritten_fields = message['rewritten_fields']
|
|
@open_files = []
|
|
end
|
|
|
|
def with_open_files
|
|
@rewritten_fields.each do |field, tmp_path|
|
|
parsed_field = Rack::Utils.parse_nested_query(field)
|
|
raise "unexpected field: #{field.inspect}" unless parsed_field.count == 1
|
|
|
|
key, value = parsed_field.first
|
|
if value.nil?
|
|
value = open_file(@request.params, key)
|
|
@open_files << value
|
|
else
|
|
value = decorate_params_value(value, @request.params[key])
|
|
end
|
|
|
|
@request.update_param(key, value)
|
|
end
|
|
|
|
yield
|
|
ensure
|
|
@open_files.each(&:close)
|
|
end
|
|
|
|
# This function calls itself recursively
|
|
def decorate_params_value(path_hash, value_hash)
|
|
unless path_hash.is_a?(Hash) && path_hash.count == 1
|
|
raise "invalid path: #{path_hash.inspect}"
|
|
end
|
|
|
|
path_key, path_value = path_hash.first
|
|
|
|
unless value_hash.is_a?(Hash) && value_hash[path_key]
|
|
raise "invalid value hash: #{value_hash.inspect}"
|
|
end
|
|
|
|
case path_value
|
|
when nil
|
|
value_hash[path_key] = open_file(value_hash.dig(path_key), '')
|
|
@open_files << value_hash[path_key]
|
|
value_hash
|
|
when Hash
|
|
decorate_params_value(path_value, value_hash[path_key])
|
|
value_hash
|
|
else
|
|
raise "unexpected path value: #{path_value.inspect}"
|
|
end
|
|
end
|
|
|
|
def open_file(params, key)
|
|
allowed_paths = [
|
|
::FileUploader.root,
|
|
Gitlab.config.uploads.storage_path,
|
|
File.join(Rails.root, 'public/uploads/tmp')
|
|
]
|
|
|
|
::UploadedFile.from_params(params, key, allowed_paths)
|
|
end
|
|
end
|
|
|
|
def initialize(app)
|
|
@app = app
|
|
end
|
|
|
|
def call(env)
|
|
encoded_message = env.delete(RACK_ENV_KEY)
|
|
return @app.call(env) if encoded_message.blank?
|
|
|
|
message = Gitlab::Workhorse.decode_jwt(encoded_message)[0]
|
|
|
|
Handler.new(env, message).with_open_files do
|
|
@app.call(env)
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|