@flytio/int-sdk

INT SDK

A standard library for integrations in Flyt. The library aims to help to speed up future integrations by extracting common parts. This way in case of any update you don't have to update the code, but only the version of the library. See original proposal.

How does it work?

The library sets up some things for you.

1. HTTP server

It runs an express server on port 8080 to expose metrics and liveness probe.

/metrics
/healthz

2. GRPC server

It creates a GRPC server and assigns your implementation to its services.

3. Prometheus

It registers Prometheus metrics and places some counters and histograms (using prom-client package) into the integration calls.

4. Axios

It exports HttpClientFactory that sets interceptors with a logger, and metrics and configures default timeout.

5. Handy wrappers

It also exports wrappers for Menu and Ordering services that simplify passing logger and httpInsntace down to the integration so you don't have to think about extracting requestId from metadata.

Example

You have to create a LoggerFactory instance that is shared between the integration factory and your implementation. This way you can keep the logs under the same app name. Also you may want to create an httpClient instance using LoggerFactory insntace to make use of metrics and logs already set up using interceptors.

import {
  IntegrationFactory,
  LoggerFactory,
  HttpClientFactory,
  OrderingServiceWrapper,
  OrderingService,
} from '@flytio/int-sdk';
import { MyOrderingImplementation, APP_NAME } from './src/my-class';

// 1. create a logger factory instance
const loggerFactory = new LoggerFactory(APP_NAME);
// 2. use logger factory instance to create http client factory instance
const httpClientFactory = new HttpClientFactory(loggerFactory);
// 3. MyOrderingImplementation implements
// OrderingService exported from @flytio/int-sdk
const myOrdering = new MyOrderingImplementation();

// 4. OrderingServiceWrapper implements
// OrderingGrpcService exported from @flytio/protos
const ordering = new OrderingServiceWrapper(
  myOrdering,
  loggerFactory,
  httpClientFactory,
);

// 5. create an integration
const integration = new IntegrationFactory({
  loggerFactory,
  appName: APP_NAME,
  ordering,
});

// 6. and make grpc server and http server listen
integration.run();

Development

Code style

We use prettier to format code before commit (using husky hooks).

Our config.

Testing

For testing we use Jest. Unit tests are placed inside __tests__ directory. Integration tests are placed in __integration-tests__ directory.

Deployment

The library is distributed as an npm package and publishing happens automatically through CircleCI after merging to master.

Versioning

We follow semantic versioning approach. To ensure you bump the version number there is a script to run before you push.