Remove handling of runner timeouts

app/jobs/application_job.rb

@@ -1,5 +0,0 @@
-# frozen_string_literal: true
-
-class ApplicationJob < ActiveJob::Base
-  queue_as :default
-end

app/jobs/runner_cleanup_job.rb

@@ -1,18 +0,0 @@
-# frozen_string_literal: true
-
-class RunnerCleanupJob < ApplicationJob
-  CLEANUP_INTERVAL = CodeOcean::Config.new(:code_ocean).read[:runner_management][:cleanup_interval].seconds
-
-  after_perform do |_job|
-    # re-schedule job
-    self.class.set(wait: CLEANUP_INTERVAL).perform_later
-  end
-
-  def perform
-    Rails.logger.debug(Time.zone.now)
-    Runner.inactive_runners.each do |runner|
-      Rails.logger.debug("Destroying runner #{runner.runner_id}, unused since #{runner.last_used}")
-      runner.destroy
-    end
-  end
-end

app/models/runner.rb

@@ -15,14 +15,10 @@ class Runner < ApplicationRecord
 
   validates :execution_environment, presence: true
   validates :user, presence: true
-  validates :time_limit, presence: true
-
-  scope :inactive_runners, -> { where('last_used < ?', Time.zone.now - UNUSED_EXPIRATION_TIME) }
 
   def self.for(user, exercise)
     execution_environment = ExecutionEnvironment.find(exercise.execution_environment_id)
-    runner = Runner.find_or_create_by(user: user, execution_environment: execution_environment,
-                                      time_limit: execution_environment.permitted_execution_time)
+    runner = Runner.find_or_create_by(user: user, execution_environment: execution_environment)
 
     return runner if runner.save
 
@@ -41,7 +37,6 @@ class Runner < ApplicationRecord
   end
 
   def execute_command(command)
-    used_now
     url = "#{runner_url}/execute"
     response = Faraday.post(url, {command: command}.to_json, HEADERS)
     if response.status == 404
@@ -75,6 +70,7 @@ class Runner < ApplicationRecord
 
   def new_runner
     url = "#{BASE_URL}/runners"
+    time_limit = CodeOcean::Config.new(:code_ocean)[:runner_management][:unused_runner_expiration_time]
     body = {executionEnvironmentId: execution_environment.id, timeLimit: time_limit}
     response = Faraday.post(url, body.to_json, HEADERS)
     response_body = parse response
@@ -89,9 +85,4 @@ class Runner < ApplicationRecord
   def parse(response)
     JSON.parse(response.body).deep_symbolize_keys
   end
-
-  def used_now
-    self.last_used = Time.zone.now
-    save
-  end
 end