add schedulable? class method to cron jobs

app/jobs/cron/cron_job.rb

@@ -3,6 +3,10 @@ class Cron::CronJob < ApplicationJob
   class_attribute :schedule_expression
 
   class << self
+    def schedulable?
+      true
+    end
+
     def schedule
       remove if cron_expression_changed?
       set(cron: cron_expression).perform_later if !scheduled?

app/jobs/cron/datagouv/export_and_publish_demarches_publiques_job.rb

@@ -15,4 +15,8 @@ class Cron::Datagouv::ExportAndPublishDemarchesPubliquesJob < Cron::CronJob
       FileUtils.rm(gzip_filepath)
     end
   end
+
+  def self.schedulable?
+    ENV.fetch('OPENDATA_ENABLED', nil) == 'enabled'
+  end
 end