Workflow Messaging Patterns
These patterns cover how external callers communicate with running Workflows — starting them on demand, sending data in, reading results back, and collecting streams of events. They build on Temporal's Signals and Updates.
Patterns in this section
Signal with Start
Starts a Workflow and delivers a Signal in a single atomic operation. If the Workflow already runs, it receives the Signal directly.
Request-Response via Updates
Sends a request into a running Workflow and receives a validated result on the same call, using an Update handler.
Event Accumulator
Collects a stream of incoming Signals into a buffer and processes them together as a batch, rather than one at a time.
Choosing a pattern
You want to send a message without checking whether the Workflow is running: use Signal with Start.
You need a result back from the Workflow, with validation: use Request-Response via Updates.
You receive many events and want to process them in batches: use the Event Accumulator to buffer and flush.
Related sections
- Entity & Lifecycle Patterns — long-lived Workflows that consume these messages over time
- Distributed Transaction Patterns — Early Return builds on the Update-with-Start mechanism