Files
codeocean/app/controllers/live_streams_controller.rb
2022-11-25 11:10:06 +01:00

80 lines
3.5 KiB
Ruby

# frozen_string_literal: true
class LiveStreamsController < ApplicationController
# Including ActionController::Live changes all actions in this controller!
# Therefore, it is extracted into a separate controller
include ActionController::Live
def download_submission_file
@submission = authorize AuthenticatedUrlHelper.retrieve!(Submission, request, force_render_host: false)
rescue Pundit::NotAuthorizedError
# TODO: Option to disable?
# Using the submission ID parameter would allow looking up the corresponding exercise ID
# Therefore, we just redirect to the root_path, but actually expect to redirect back (that should work!)
skip_authorization
redirect_back(fallback_location: root_path, alert: t('exercises.download_file_tree.gone'))
else
desired_file = params[:filename].to_s
runner = Runner.for(current_user, @submission.exercise.execution_environment)
fallback_location = implement_exercise_path(@submission.exercise)
send_runner_file(runner, desired_file, fallback_location)
end
def download_arbitrary_file
@execution_environment = authorize ExecutionEnvironment.find(params[:id])
desired_file = params[:filename].to_s
runner = Runner.for(current_user, @execution_environment)
fallback_location = shell_execution_environment_path(@execution_environment)
privileged = params[:sudo] || @execution_environment.privileged_execution?
send_runner_file(runner, desired_file, fallback_location, privileged:)
end
private
def send_runner_file(runner, desired_file, redirect_fallback = root_path, privileged: false)
filename = File.basename(desired_file)
send_stream(filename:, type: 'application/octet-stream', disposition: 'attachment') do |stream|
runner.download_file desired_file, privileged_execution: privileged do |chunk, overall_size, _content_type|
unless response.committed?
# Disable Rack::ETag, which would otherwise cause the response to be cached
# See https://github.com/rack/rack/issues/1619#issuecomment-848460528
response.set_header('Last-Modified', Time.now.httpdate)
response.set_header('Content-Length', overall_size) if overall_size
# We set the content type to 'application/octet-stream' in send_stream
# response.set_header('Content-Type', content_type) if content_type
# Commit the response headers immediately, as streaming would otherwise remove the Content-Length header
# This will prevent chunked transfer encoding from being used, which is okay as we know the overall size
# See https://github.com/rails/rails/issues/18714
response.commit!
end
begin
stream.write chunk
rescue ClientDisconnected
# The client disconnected, so we stop streaming
break
end
end
rescue Runner::Error
redirect_back(fallback_location: redirect_fallback, alert: t('exercises.download_file_tree.gone'))
end
end
# TODO: Taken from Rails 7, remove when upgrading
# rubocop:disable all
def send_stream(filename:, disposition: "attachment", type: nil)
response.headers["Content-Type"] =
(type.is_a?(Symbol) ? Mime[type].to_s : type) ||
Mime::Type.lookup_by_extension(File.extname(filename).downcase.delete(".")) ||
"application/octet-stream"
response.headers["Content-Disposition"] =
ActionDispatch::Http::ContentDisposition.format(disposition: disposition, filename: filename)
yield response.stream
ensure
response.stream.close
end
# rubocop:enable all
end