myRetail products service

This is a microservice responsible for exposing product data via a RESTful api. It is designed to run as a cloud native application, in a Docker container. Currently the following routes are available:

• GET /products/{productId} to get product name, price for a given product id. Response format:

{
    "id": 13860428,
    "name": "The Big Lebowski (Blu-ray)",
    "current_price": {
        "value": 22.99,
        "currency_code": "USD"
    }
}

• PUT /products/{productId} to update product pricing for a given product id. Payload format:

{
    "current_price": {
        "value": 22.10,
        "currency_code": "USD"
    }
}

This service relies on external backends (rest api and MongoDB instance). Being a cloud native application, the service has zero knowledge of how backend components are provisioned or initialized. It only expects following characteristics:

• MongoDB: containing mr-products database with prices collection, where each price document contains the following attributes:

{
    "product_id": "numerical product id",
    "value": "currency decimal format",
    "currency_code": "USD, EUR, or GBP"
}

• RESTful api: Exposing <baseUrl>/pdb/tcin/{productId} route. The base url is configurable via products_base_url environment variable. The route above is expected to contain following structure:

{
  "product": {
    "item": {
     "product_description": {
      "title": "product title"
     }
   }
 }
}

Technologies used:

• ExpressJS: web application framework
• mongodb: sdk to connect to MongoDB instance
• morgan: for logging http requests
• nconf: for configuring the application
• prom-client: to allow for application monitoring
• request-promise-native: http client to interact with internal products api

Setup

To Run for development and demos (requires nodejs and docker)

• Start a MongoDB docker instance as follows

mkdir -p ~/data
docker run --name mdb -d -p 27017:27017 -v ~/data:/data/db mongo

• Connect to the MongoDB instance:

docker exec -it mdb mongo 'mongodb://localhost:27017/mr-products'

• Seed some prices and exit:

db.prices.insertMany([
    {product_id: 13860428, value: 11.99,currency_code: 'USD'},
    {product_id: 15117729, value: 2.99,currency_code: 'GBP'},
    {product_id: 16483589, value: 3.99,currency_code: 'USD'},
    {product_id: 16696652, value: 1.99,currency_code: 'USD'},
    {product_id: 16752456, value: 200,currency_code: 'EUR'},
    {product_id: 15643793, value: 0.21,currency_code: 'USD'},
])

• Create configuration.json at root of this project (adjacent to package.json) with following content and update products_base_url to appropriate value where the rest api is available such as https://products.myretail.com/v2

{
  "products_base_url": "",
  "mongodb_url": "mongodb://localhost:27017",
  "pricing_api_key": "myapikey"
}

• Finally start the application

npm install
npm run start

• Product details example:

curl --location --request GET 'http://localhost:9090/products/13860428'

• Update product pricing example:

curl --location --request PUT 'http://localhost:9090/products/13860428' \
--header 'Content-Type: application/json' \
--header 'x-api-key: myapikey' \
--data-raw '{
    "current_price": {
        "value": 33.10,
        "currency_code": "USD"
    }
}'

To Run Tests (requires nodejs)

npm install
npm run test

To Run in production mode (requires docker)

• Build the docker image:

docker build -t myretail .

• Start docker container using below command after filling the values for environment variables:

docker run -d \
-e products_base_url= \
-e mongodb_url= \
-e pricing_api_key= \
-p 9090:9090 myretail