Job Lifecycle

app/models/solid_queue/job.rb

@@ -4,6 +4,7 @@ module SolidQueue
   class Job < Record
     class EnqueueError < StandardError; end
 
+    # Job Lifecycle 1: When MyJob.perform_later(args) is called, the job is executed.
     include Executable, Clearable, Recurrable
 
     serialize :arguments, coder: JSON

app/models/solid_queue/job/concurrency_controls.rb

@@ -39,8 +39,11 @@ def concurrency_on_conflict
         end
 
         def acquire_concurrency_lock
+          # Job Lifecycle 5 - If our job had something like:  limits_concurrency to: 2, key: ->(contact) { contact.account }, duration: 5.minutes
+          # then we would use the key to acquire a lock.
           return true unless concurrency_limited?
 
+          # Job Lifecycle 6 - The method delegates to SolidQueue::Semaphore.wait(self), passing the job instance
           Semaphore.wait(self)
         end
 

app/models/solid_queue/job/executable.rb

@@ -11,6 +11,7 @@ module Executable
         has_one :ready_execution
         has_one :claimed_execution
 
+        # Job Lifecycle 2: After the job is created, it is prepared for execution.
         after_create :prepare_for_execution
 
         scope :finished, -> { where.not(finished_at: nil) }
@@ -57,6 +58,7 @@ def dispatched_and_blocked(jobs)
         define_method("#{status}?") { public_send("#{status}_execution").present? }
       end
 
+      # Job Lifecycle 3: After the job is created, it is prepared for execution.
       def prepare_for_execution
         if due? then dispatch
         else
@@ -65,6 +67,7 @@ def prepare_for_execution
       end
 
       def dispatch
+        # Job Lifecycle 4: If we are able to acquire a concurrency lock, we proceed to ready the job for execution.
         if acquire_concurrency_lock then ready
         else
           handle_concurrency_conflict
@@ -101,6 +104,7 @@ def discard
 
       private
         def ready
+          # Job Lifecycle 11 - Create a ReadyExecution record for the job.
           ReadyExecution.create_or_find_by!(job_id: id)
         end
 

app/models/solid_queue/semaphore.rb

@@ -40,7 +40,9 @@ def initialize(job)
       end
 
       def wait
+        # Job Lifecycle 7 - Check if a semaphore exists for the job's concurrency key.
         if semaphore = Semaphore.find_by(key: key)
+          # Job Lifecycle 8 - Check if the semaphore's value is greater than 0 and attempt to decrement it.
           semaphore.value > 0 && attempt_decrement
         else
           attempt_creation
@@ -67,10 +69,12 @@ def check_limit_or_decrement
         end
 
         def attempt_decrement
+          # Job Lifecycle 9 - Decement the semaphore's value and update its expiration time.
           Semaphore.available.where(key: key).update_all([ "value = value - 1, expires_at = ?", expires_at ]) > 0
         end
 
         def attempt_increment
+          # Job Lifecycle 10 - Increment the semaphore's value and update its expiration time.
           Semaphore.where(key: key, value: ...limit).update_all([ "value = value + 1, expires_at = ?", expires_at ]) > 0
         end