ratpack-quickstart-demo

Photo: http://notallwhowanderarelost.com/rat-pack/

Hello and welcome to the repository containing source code from my Practical quickstart to Ratpack talk.

Application architecture

This demo simulates following problem. Imagine two microservices - product-service and recommendations-service.

The first one is just a simple REST service that allows you to read information about given product. But this application does not simply translate HTTP request to some SQL query for example. It communicates with other services, databases or even file system instead. It means that receiving a product information will take some time, because some information might be taken from multiple web services while some of them might be loaded from the database. We will simulate latencies in this case (from 100 ms to 1500 ms).

recommendation-service is smart enough to suggest recommendations to the client, but it doesn't know anything about the products. It retrieves product information from product-service via HTTP GET request. We won't focus on creating recommendations engine, we will hardcode products IDs and we will focus only on communication between both services.

Exemplary requests

Below you can find exemplary requests triggered with HTTPie command line tool.

http localhost:5050/product/PROD-001

HTTP/1.1 200 OK
content-encoding: gzip
content-type: application/json
transfer-encoding: chunked

{
    "id": "PROD-001",
    "name": "Learning Ratpack",
    "price": 29.99
}

http localhost:5050/product/PROD-006

HTTP/1.1 404 Not Found
content-encoding: gzip
content-type: application/json
transfer-encoding: chunked

{
    "message": "Product not found"
}

http localhost:5050/recommendations 

HTTP/1.1 200 OK
content-encoding: gzip
content-type: application/json
transfer-encoding: chunked

{
    "discount": "-20%",
    "products": [
        {
            "id": "PROD-001",
            "name": "Learning Ratpack",
            "price": 23.992
        },
        {
            "id": "PROD-002",
            "name": "Netty In Action",
            "price": 31.992
        }
    ],
    "total": 2
}