Your First Temporal Workflow in Go#

This article establishes the patterns used throughout the Temporal series: dependency injection for testable activities, idempotency for safe retries, and a clean worker binary. Every subsequent article builds on these foundations.

All code lives in the companion repo at github.com/statherm/temporal-examples. For background, see Introduction to Temporal and Namespaces and Task Queues.

Project Structure#

The companion repo organizes code by domain:

temporal-examples/
  cmd/worker/main.go         # Worker binary
  cmd/starter/main.go        # Workflow starter CLI
  internal/container/
    activities.go             # Activity implementations with DI
    workflow.go               # Workflow definitions
    types.go                  # Interfaces and types
  Makefile

Workflows and Activities#

A workflow is a deterministic function that orchestrates work. It takes workflow.Context, must not perform side effects, and dispatches work through activities. Activities use standard context.Context and perform real I/O:

Building a Temporal Worker Bridge#

The architecture article evaluated three cross-cluster communication patterns and identified the worker bridge as the best fit for most open-source Temporal deployments. This article builds the bridge.

The worker bridge is a single binary that holds connections to two Temporal clusters. It polls Cluster A for tasks on a dedicated queue and executes those tasks using Cluster B’s resources – its Temporal client, databases, APIs, and services. From Cluster A’s perspective, the bridge is just another worker. From Cluster B’s perspective, the bridge is just another client starting workflows.