speculate

type Controller ¶

type Controller struct {
	// contains filtered or unexported fields
}

Controller handles speculate queue messages.

Naive happy-path algorithm: assume every in-flight build will pass and treat batch.Dependencies + [batch.ID] as the single speculation chain. Per invocation, the controller advances the batch one step in the state machine:

• Created → publish to build, transition to Speculating.
• Speculating → if all deps are Succeeded, publish to merge and transition to Merging; otherwise no-op (or fail-fast if a dep is in a non-succeeding terminal state).
• Cancelling → cancel any in-flight Build entity, respeculate dependents, CAS to terminal Cancelled, publish to conclude. The cancel controller hands the batch off in this state and speculate drives it to terminal.
• Merging → no-op (owned by the merge controller).
• Terminal → re-fan-out to conclude for self-healing in case a prior publish was lost. For terminal Cancelled, also re-fan-out dependents so a crash between the terminal CAS and the dependent publish does not strand them.

The controller is re-triggered on every relevant downstream event (buildsignal, merge), so each call simply re-evaluates the current state and either advances or waits.

func NewController(
	logger *zap.SugaredLogger,
	scope tally.Scope,
	stores storage.Factory,
	registry consumer.TopicRegistry,
	topicKey consumer.TopicKey,
	consumerGroup string,
) *Controller

func (c *Controller) ConsumerGroup() string

func (c *Controller) Name() string

func (c *Controller) Process(ctx context.Context, delivery consumer.Delivery) error

func (c *Controller) TopicKey() consumer.TopicKey