Files
codeocean/app/controllers/live_streams_controller.rb

72 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
before_action :set_content_type_nosniff
skip_before_action :deny_access_from_render_host, only: :download_submission_file
skip_before_action :verify_authenticity_token, only: :download_submission_file
skip_before_action :set_sentry_context, only: :download_submission_file
before_action :require_user!, except: :download_submission_file
def download_submission_file
@submission = AuthenticatedUrlHelper.retrieve!(Submission, request)
# Set @current_user with the corresponding learner for Pundit checks
@current_user = @submission.user
authorize @submission
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_or_to(root_path, allow_other_host: true, alert: t('exercises.download_file_tree.gone'))
else
desired_file = params[:filename].to_s
runner = Runner.for(current_contributor, @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]}" # The filename given is absolute; this is an admin-only action.
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:, exclusive: false)
end
private
def send_runner_file(runner, desired_file, redirect_fallback = root_path, privileged: false, exclusive: true)
filename = File.basename(desired_file)
send_stream(filename:, type: 'application/octet-stream', disposition: 'attachment') do |stream|
runner.download_file(desired_file, privileged_execution: privileged, exclusive:) 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_or_to(redirect_fallback, alert: t('exercises.download_file_tree.gone'))
end
end
end