fix(be): set a key before incrby for none existing key (#19)

Author: noamilshtein

src/redis.ts

@@ -117,7 +117,9 @@ class buildRedisStoreWithConfig implements RedisStore {
     return await this.redisCache.multi().set(key, updateFunction(await this.get(key))).get(key).exec();
   }
 
-  public async incrBy(key: string, incrementBy: number): Promise<number> {
+  public async incrBy(key: string, incrementBy: number, ttl?: Milliseconds): Promise<number> {
+    const ttlValue = this.getTtl(ttl);
+    await this.redisCache.set(key, 0, {PX: ttlValue, NX: true});
     return await this.redisCache.incrBy(key, incrementBy);
   }
 

test/redis.test.ts

@@ -88,12 +88,12 @@ describe('Redis Store', () => {
 
   it('should increment a value', async () => {
     const key = 'testKey';
-    const value = 1;
 
-    await redisClient.set(key, value);
-    const numberIncrBy = await redisClient.incrBy(key, 1);
+    const numberIncrBy = await redisClient.incrBy(key, 2);
 
     const retrievedValue = await redisClient.get(key);
+    const ttl = await redisClient.ttl(key);
+    expect(ttl).to.not.equal(-1);
     expect(numberIncrBy).toEqual(2);
     expect(retrievedValue).toEqual(2);
   });