This tutorial implements a serverless application and deploy it to AWS Lambda using Serverless Framework
See Using AWS SAM, if you prefer AWS SAM over Serverless Framework.
If you do not have one, create a database following this guide.
If you do not have it already install serverless framework via:
npm install -g serverless
In any folder run
serverless as below:
Inside the project folder create a node project with the command:
Then install the redis client with:
Edit handler.js file as below. Replace the Redis URL (copy ioredis url from your Upstash console).
In the project folder run:
The output will be:
Run your function via
serverless invoke -f hello:
You can also test your function using AWS console. In your AWS Lambda section, click on your function. Scroll down to the code sections and click on the
Test button on the top right.
Congratulations, now your lambda function inserts entry to your Upstash database.
- You can write and deploy another function to just get values from the database.
- You can integrate API Gateway so you can call your function via http.
- You can learn about how to monitor your functions from CloudWatch as described here.
Although Redis connections are very lightweight, a new connection inside each Lambda function can cause a notable latency. On the other hand, reusing Redis connections inside the AWS Lambda functions has its own drawbacks. When AWS scales out Lambda functions, the number of open connections can rapidly increase. Fortunately, Upstash detects and terminates the idle and zombie connections thanks to its smart connection handling algorithm. Thanks to this algorithm; we have been recommending caching your Redis connection in serverless functions.
See the blog post about the database connections in serverless functions.