Temporal Trip Booking

Overview

The Temporal trip booking workflow is responsible for coordinating the booking of a vacation package, consisting of a car, hotel, and flight reservation. In the event of a failure at any point during the booking process, the workflow will trigger compensating actions to undo any previous bookings. This is an implementation of a Saga pattern. A Saga ensures that a business process is atomic, that is, it executes observably equivalent to completely or not at all.

Running

Prerequisites:

• Python >= 3.7
• Poetry
• Local Temporal server running

With this repository cloned, run the following at the root of the directory:

poetry install --no-root

That loads all required dependencies.

Then run the worker and workflow.

cd app-python
./start_worker.sh

cd ui
./start_ui.sh

Demo: Happy Path

Enter your booking information in the Flask app http://127.0.0.1:5000, then see the tasks in the Web UI at http://localhost:8233/.

Demo: Durable Path

Use ctrl+c to kill the worker process at any time during workflow execution. Restart the worker to resume the function execution in a new process.

Demo: Recover Forward (retries)

Add the word "Flaky" to the Car input field. The car booking activity will fail 5 times, and succeed on the 6th attempt.

Demo: Recover Forward (bug in code)

Add the word "Buggy" to the Hotel input field. The hotel booking activity will fail indefinitely - until the bug in the activity function is fixed, and the worker is restarted.

Demo: Recover Backward (rollback)

Add the word "Invalid" to the Flight input field. The flight booking activity will fail with and non-retryable error, and the hotel and car bookings will be rolled back.