Feature Flags client

NodeJS client grpc lib, for featureflags service. Provides abilitty to gracefull set and updates for ur features.

.proto files were taken directly from repo above. They should be uploaded in some place from the root repo on deploy i guess

API

FeatureClient is the base class. With it's constructor u will init grpc client, wich will call ExchangeRequest every 5 min. in async manner. So it shouldn't hurt ur eventloop much, or app performance, coz of inmemory caching and time interval.

So u do this on application start:

import { FeatureClient, Variable, Types } from '@evo/featureflags-client';

// Ur default flags dict
const Flags = {
  TEST: false,
  NODE: false
};

const featureClient = new FeatureClient(
  'thecorp', // project name
  'grpc:50051', // grpc-url
  Flags, // default flags
  [
    new Variable('username', Types.STRING) // ur controll values for Checks
  ],
  true, // isDebugg mode
);

In ur controllers, or somewhere when ur need ur features to work properly, call getFlags, and provide there context = {}. Ctx is the object with Variable as a key, and a value u want checks to depend on.

import { getFlags } from '@evo/featureflags-client';

// ready to use object with proceeded checks
const flags = getFlags({ username: 'Petro' });

if (flags.TEST) doSomeThing();

Left to implement

There several features, that exists in python flags.lib , that u are free to extend:

• StatsController - Accumulates interval/flag/requests count
• Tracer - Accumulates request/flag/values