Temporal Training Exercise - Go Solution

Complete Go implementation for progressive Temporal training exercises.

Prerequisites

• Go 1.21+
• Temporal CLI

Installing Temporal CLI

macOS (Homebrew):

brew install temporal

Linux:

curl -sSf https://temporal.download/cli.sh | sh

Windows:

scoop install temporal-cli

Or download directly: Visit https://github.com/temporalio/cli/releases and download the appropriate binary for your platform.

Setup

1. Start Temporal dev server with AccountId search attribute:

temporal server start-dev --search-attribute AccountId=Text

2. Install dependencies:

go mod download

Exercise Progression

Exercise 1: Hello Temporal (30 min)

• Basic Workflow and Activity setup
• Worker registration and execution

Exercise 2: Money Transfer Basics (45 min)

• Multiple activities (withdraw, deposit, refund)
• Signal-based approval mechanism
• workflow.Await() for conditional waiting
• Basic error handling and compensation

Exercise 3: Query Handlers (35 min)

• Query methods for workflow state inspection
• Status tracking throughout execution
• External workflow monitoring
• Signal vs Query differences

Exercise 4: Visibility & Monitoring (30 min)

• Custom Search Attributes (AccountId)
• Upsert Search Attributes from workflows
• Workflow filtering and discovery

Exercise 5: User Metadata & Activity Summaries (30 min)

• Activity summaries for better observability
• Enhanced monitoring in Temporal Web UI

Exercise 6: Testing Strategy (45 min)

• Unit tests with testsuite
• Time skipping for fast tests
• Activity mocking with testify/mock
• Search attribute registration in tests

Exercise 7: Manual Activity Retry (40 min)

• Manual retry pattern using signals
• Invalid data handling scenarios
• Disabling automatic retries
• Interactive retry commands

Running Exercises

Exercise 1 (Hello Temporal)

# Start worker
go run solution1/worker/main.go
# Run workflow (in another terminal)
go run solution1/starter/main.go

Exercise 2 (Money Transfer Basics)

# Start worker
go run solution2/worker/main.go
# Run workflow (in another terminal)
go run solution2/starter/main.go

Exercise 3 (Query Handlers)

# Start worker
go run solution3/worker/main.go
# Run workflow (in another terminal)
go run solution3/starter/main.go

Exercise 4 (Visibility & Monitoring)

# Start worker
go run solution4/worker/main.go
# Run workflow (in another terminal)
go run solution4/starter/main.go

Exercise 5 (User Metadata & Activity Summaries)

# Start worker
go run solution5/worker/main.go
# Run workflow (in another terminal)
go run solution5/starter/main.go

Exercise 6 (Testing Strategy)

# Run tests
go test ./solution6 -v

Exercise 7 (Manual Activity Retry)

# Start worker
go run solution7/worker/main.go
# Run workflow (in another terminal)
go run solution7/starter/main.go
# Or send retry signal manually
temporal workflow signal \
  --workflow-id money-transfer-workflow \
  --name retry \
  --input '{"Key":"fromAccount","Value":"account-123"}'

Key Features Implemented

• Go Structs: Modern data structures
• Activity Retry: Configurable retry policies
• Signal/Query: Workflow interaction patterns
• Search Attributes: Custom filtering
• Activity Summaries: Enhanced observability
• Compensation: Saga pattern for rollbacks
• Testing: Time-skipping unit tests with testify
• Error Handling: Distinguishes activity vs workflow failures
• Manual Retry: Signal-based retry for failed activities

Project Structure

.
├── solution1/          # Hello Temporal
├── solution2/          # Money Transfer Basics
├── solution3/          # Query Handlers
├── solution4/          # Visibility & Monitoring
├── solution5/          # Activity Summaries
├── solution6/          # Testing Strategy
├── solution7/          # Manual Activity Retry
└── go.mod

Each solution contains:

• workflow.go - Workflow implementation
• activities.go - Activity implementations
• models.go - Data structures
• worker/main.go - Worker startup
• starter/main.go - Workflow starter
• workflow_test.go - Unit tests (solution6)