metropolis 0.1.3

Microservice gateway using Nats

Metropolis (Python Microservice Gateway with NATS)

Can we make simple, scalable, observable, operable service gateway?

Architecture Concept

+- Node-1 --+  +- Node-2 -+  +- Node-3 --+  +- Node-4 -+
|           |  |          |  |           |  |          |
| Worker-a  |  |          |  |           |  | Worker-d |
| Worker-b  |  | Worker-c |  | Worker-a  |  | Worker-c |
|    |      |  |    |     |  |    |      |  |    |     |
|   NATS ========= NATS ======================= NATS   |
|    |      |  |          |  |    |      |  |          |
|  Gateway  |  |          |  |  Gateway  |  |          |
|    |      |  |          |  |    |      |  |          |
+--- | -----+  +----------+  +--- | -----+  +----------+
     |                            |
     +--------------+-------------+
                    |
                  Ingress

Components

Nats

Message bus

Worker

Business Logic worker

Gateway

Service gateway

Example

Define Worker task

from metropolis import Worker


worker = Worker(nats='nats://localhost:4222')


@worker.task(subject='foo.bar', queue='worker')
def mytask(data, *args, **kwargs):
    """Simple task which returns reverse string
    """

    return data[0][::-1]


worker.run()

Define Gateway

from metropolis import Gateway
import settings


gateway = Gateway(nats='nats://nats:4222')
gateway.app.run(host='0.0.0.0')