made a util for the rate limiter to get config

api/src/middleware/rate-limiter.ts

@@ -5,53 +5,13 @@
  *  in future
  */
 import { RequestHandler } from 'express';
-import redis from 'redis';
 import asyncHandler from 'express-async-handler';
-import { RateLimiterRedis, RateLimiterMemory } from 'rate-limiter-flexible';
 import { HitRateLimitException } from '../exceptions';
-import { RedisNotFoundException } from '../exceptions';
-import env from '../env';
-
-const redisClient = redis.createClient({
-	enable_offline_queue: false,
-	host: env.REDIS_HOST,
-	port: env.REDIS_PORT,
-	password: env.REDIS_PASSWORD,
-});
+import rateLimiterConfig from '../utils/get-rate-limiter-config';
 
 const rateLimiter: RequestHandler = asyncHandler(async (req, res, next) => {
-	// options for the rate limiter are set below. Opts can be found
-	// at https://github.com/animir/node-rate-limiter-flexible/wiki/Options
-	// more basic for memory store
-	const opts = {
-		points: env.CONSUMED_POINTS_LIMIT, // Number of points
-		duration: env.CONSUMED_RESET_DURATION, // Number of seconds before consumed points are reset.
-		keyPrefix: 'rlflx', // must be unique for limiters with different purpose
-	};
-
-	let rateLimiterSet = new RateLimiterMemory(opts);
-
-	if (env.RATE_LIMIT_TYPE === 'redis') {
-		const redisOpts = {
-			...opts,
-			storeClient: redisClient,
-			// Custom
-			execEvenly: env.EXEC_EVENLY, // delay actions after first action - this may need adjusting (leaky bucket)
-			blockDuration: env.BLOCK_POINT_DURATION, // Do not block if consumed more than points
-			inmemoryBlockOnConsumed: env.INMEMORY_BLOCK_CONSUMED, // eg if 200 points consumed
-			inmemoryBlockDuration: env.INMEMEMORY_BLOCK_DURATION, // block for certain amount of seconds
-		};
-
-		rateLimiterSet = new RateLimiterRedis(redisOpts);
-
-		// first need to check that redis is running!
-		if (!redisClient) {
-			throw new RedisNotFoundException('Redis client does not exist');
-		}
-	}
-
 	try {
-		await rateLimiterSet.consume(req.ip);
+		await rateLimiterConfig.consume(req.ip);
 	} catch (rejRes) {
 		// If there is no error, rateLimiterRedis promise rejected with number of ms before next request allowed
 		const secs = Math.round(rejRes.msBeforeNext / 1000) || 1;

api/src/utils/get-rate-limiter-config.ts

@@ -0,0 +1,85 @@
+import redis from 'redis';
+import {
+	RateLimiterRedis,
+	RateLimiterMemory,
+	IRateLimiterStoreOptions,
+	IRateLimiterOptions,
+} from 'rate-limiter-flexible';
+import { RedisNotFoundException } from '../exceptions';
+
+import env from '../env';
+
+// options for the rate limiter are set below. Opts can be found
+// at https://github.com/animir/node-rate-limiter-flexible/wiki/Options
+
+const redisClient = redis.createClient({
+	enable_offline_queue: false,
+	host: env.REDIS_HOST,
+	port: env.REDIS_PORT,
+	password: env.REDIS_PASSWORD,
+});
+
+let rateLimiterConfig = new RateLimiterMemory(getRateLimiterConfig());
+// need to pick redis or memory
+if (env.RATE_LIMIT_TYPE === 'redis') {
+	rateLimiterConfig = new RateLimiterRedis(getRateLimiterRedisConfig());
+}
+// first need to check that redis is running!
+
+if (!redisClient) {
+	throw new RedisNotFoundException('Redis client does not exist');
+}
+
+export default rateLimiterConfig;
+
+function getRateLimiterConfig(): IRateLimiterOptions {
+	const config: any = {};
+	config.keyPrefix = 'rlflx';
+	for (const [key, value] of Object.entries(env)) {
+		if (key === 'CONSUMED_POINTS_LIMIT') {
+			config.points = value;
+			continue;
+		}
+		if (key === 'CONSUMED_RESET_DURATION') {
+			config.duration = value;
+			continue;
+		}
+	}
+
+	return config;
+}
+
+function getRateLimiterRedisConfig(): IRateLimiterStoreOptions {
+	const redisConfig: any = {};
+	redisConfig.keyPrefix = 'rlflx';
+	redisConfig.storeClient = redisClient;
+
+	for (const [key, value] of Object.entries(env)) {
+		if (key === 'CONSUMED_POINTS_LIMIT') {
+			redisConfig.points = value;
+			continue;
+		}
+		if (key === 'CONSUMED_RESET_DURATION') {
+			redisConfig.duration = value;
+			continue;
+		}
+		if (key === 'EXEC_EVENLY') {
+			redisConfig.execEvenly = value;
+			continue;
+		}
+		if (key === 'BLOCK_POINT_DURATION') {
+			redisConfig.blockDuration = value;
+			continue;
+		}
+		if (key === 'INMEMORY_BLOCK_CONSUMED') {
+			redisConfig.inmemoryBlockOnConsumed = value;
+			continue;
+		}
+		if (key === 'INMEMEMORY_BLOCK_DURATION') {
+			redisConfig.inmemoryBlockDuration = value;
+			continue;
+		}
+	}
+
+	return redisConfig;
+}