Proof of concept microservices distribution

Getting Started

1. Clone or download this repository.
2. Install docker (enable Linux containers - right click the docker icon in the system tray and select 'Switch to Linux containers' if already using Windows Containers).
3. Update the ip address in docker-compose.yml to your ip.
4. Go to the repository root and run docker-compose up.

To query the api you can import Paris.postman_collection.json. The two apis are running at localhost:3000 and localhost:3001 respectively - in future a reverse proxy could be used to allow access on a single port. Web interfaces are available for the two databases at localhost:8081 and localhost:8082.

Architecture

Consists of two microservices:

1. units (node.js)
2. materials (node.js)

Database structure

Both have dedicated MongoDb databases:

1. units collections:
   • units (primary data store)
     • _id
     • name
     • shortName
     • type (0 = length, 1 = density) - simplified
   • materials (material cache for unit deletion) ** TODO **
     • _id
     • densityUnitId
2. materials collections:
   • materials (primary data store)
     • _id
     • name
     • externalName
     • ultimateTensileStrength
     • strainHardeningCoefficient
     • bendingMaterialType
     • density
       • value
       • unitId
   • units (unit cache for material density validation):
     • _id
     • shortName

Communication

Inter-service communication is achieved using Apache Kafka which operates a publish-subscribe model. Example event:

{
  "mode": "create",
  "value": {
    "_id": "8277f7c1-eabe-4774-ae80-07c97e31eeed",
    "name": "kilograms per cubic metre",
    "shortName": "kg/m3",
    "type": 1
  }
}

Endpoints

All endpoints are included in Paris.postman_collection.json.

Limitations

• No authentication or user management
• No concurrency checks
• Limited validation (unique name check & unit existence check is about it!)