ShoppingCartExamples Solution

Welcome to the ShoppingCartExamples solution, a simple example demonstrating various implementations of a simple shopping cart using Orleans in .NET.

This solution was created to support the Temporal Talk in London Scaling Workflow Systems with Temporal, .NET, and Orleans: An Integrated Approach and includes three distinct variants.

Each variant showcases different approaches to managing workflows, error handling, and resilience within a .NET application.

Variants Overview

PureCSharp ShoppingCart Example: Implements a basic shopping cart using standard C# and .NET features, focusing on simplicity and clarity.
Polly ShoppingCart Example: Utilizes the Polly library to apply advanced resilience patterns like retries, circuit breakers, and timeout policies.
Temporal ShoppingCart Example: Leverages Temporal.io's capabilities for orchestrating workflows, providing fault tolerance and seamless retries.

Prerequisites

.NET SDK
Visual Studio or another compatible IDE
Docker and Docker Compose (for the Temporal Workflow Demo)

Getting Started

To begin, ensure you have cloned the repository and have the necessary prerequisites installed on your machine.

Open the Solution:
- Open Visual Studio.
- Navigate to File > Open > Project/Solution.
- Locate and select the ShoppingCartExamples.sln file.
Restore Dependencies:
- Right-click on the solution in Solution Explorer.
- Select "Restore NuGet Packages".

Testing the ShoppingCart Example

Follow these steps to test the ShoppingCart Example using the Swagger UI. Ensure you use the same cartId for all the API actions during the test.

Step 1: Add Products to Cart

Use the /cart/add endpoint to add products to your shopping cart.

Endpoint: POST /cart/add
Query Parameter: cartId (Choose any integer, e.g., 1)
Request Body: Provide product details. You can use the default payload if you wish.

Example payload:
```
{
  "name": "Example Product"
}
```

Step 2: View Cart Contents

After adding products, check the contents of your cart using the /cart/view endpoint.

Endpoint: GET /cart/view
Query Parameter: cartId (Use the same cartId as in Step 1)

This step verifies that the products have been successfully added to the cart.

Step 3: Checkout

Finally, trigger the checkout workflow using the /cart/checkout endpoint.

Endpoint: POST /cart/checkout
Query Parameter: cartId (Use the same cartId as in previous steps)

This action will process the items in your cart and perform the checkout workflow.

Accessing Swagger UI

To access the Swagger UI and perform these actions:

Navigate to https://localhost:59855/swagger/index.html in your browser.
Use the Swagger UI to interact with the above endpoints.

Running the Variants

To run a specific variant, set it as the startup project:

Temporal Workflow Demo:
- Navigate to the ShoppingCartExample.Temporal project.
- Right-click and choose 'Set as Startup Project'.
- Follow the project-specific README for running the Temporal server.
PureCSharp ShoppingCart Example:
- Navigate to the ShoppingCartExample.PureCSharp project.
- Right-click and choose 'Set as Startup Project'.
- Start the application.
Polly ShoppingCart Example:
- Navigate to the ShoppingCartExample.Polly project.
- Right-click and choose 'Set as Startup Project'.
- Start the application.

Variant-Specific Instructions

Each variant has its own set of instructions and prerequisites:

Please refer to these README files for detailed instructions on running and interacting with each variant.

Conclusion

The ShoppingCartExamples solution is designed to provide a hands-on look at different architectural approaches in .NET applications. Whether you're interested in workflow orchestration, fundamental C# implementations, or resilience patterns, this solution offers very basic insight.

Further Enhancement

A more realistic scale implementation of the Temporal example including:

Non-Blocking execution of the workflow - typically this would return to the user to config acceptance of the order and the workflow activities would then drive interaction with the user as the workflow progressed.

lulzzz / OrleansAndTemporal