Error When an Invalid Recurring Task is Configured

Resolves #414

lib/solid_queue/scheduler.rb

@@ -35,7 +35,15 @@ def run
       end
 
       def schedule_recurring_tasks
-        recurring_schedule.schedule_tasks
+        if recurring_schedule.valid?
+          recurring_schedule.schedule_tasks
+        else
+          error_messages = recurring_schedule.invalid_tasks.map do |task|
+            "#{task.key}: #{task.errors.full_messages.to_sentence}"
+          end.join(", ")
+
+          raise "Invalid recurring tasks: #{error_messages}"
+        end
       end
 
       def unschedule_recurring_tasks

lib/solid_queue/scheduler/recurring_schedule.rb

@@ -4,17 +4,21 @@ module SolidQueue
   class Scheduler::RecurringSchedule
     include AppExecutor
 
-    attr_reader :configured_tasks, :scheduled_tasks
+    attr_reader :configured_tasks, :invalid_tasks, :scheduled_tasks
 
     def initialize(tasks)
-      @configured_tasks = Array(tasks).map { |task| SolidQueue::RecurringTask.wrap(task) }.select(&:valid?)
+      @configured_tasks, @invalid_tasks = Array(tasks).map { |task| SolidQueue::RecurringTask.wrap(task) }.partition(&:valid?)
       @scheduled_tasks = Concurrent::Hash.new
     end
 
     def empty?
       configured_tasks.empty?
     end
 
+    def valid?
+      invalid_tasks.empty?
+    end
+
     def schedule_tasks
       wrap_in_app_executor do
         persist_tasks

test/unit/scheduler_test.rb

@@ -17,6 +17,16 @@ class SchedulerTest < ActiveSupport::TestCase
     scheduler.stop
   end
 
+  test "recurring schedule has an invalid task" do
+    invalid_recurring_tasks = { example_task: { class: "BarBarBarBarJob", schedule: "every hour", args: 42 } }
+
+    error = assert_raises(RuntimeError) do
+      SolidQueue::Scheduler.new(recurring_tasks: invalid_recurring_tasks).tap(&:start)
+    end
+
+    assert_equal "Invalid recurring tasks: example_task: Class name doesn't correspond to an existing class", error.message
+  end
+
   test "run more than one instance of the scheduler with recurring tasks" do
     recurring_tasks = { example_task: { class: "AddToBufferJob", schedule: "every second", args: 42 } }
     schedulers = 2.times.collect do