Categories
OpenWhisk Serverless

Apache OpenWhisk hello world

In this post we see how to deploy Apache OpenWhisk, an open source serverless platform, and how to create an example of hello world action.

Categories
AWS Kubernetes

How to create a Kubernetes cluster using Amazon AWS EC2

In the previous examples we used Kubernetes with Docker Desktop for an application composed of Node.js microservices and a Redis database.

In this post we see a simple example about how we can create our Kubernetes cluster with three CentOS 8 virtual machines provided by Amazon AWS EC2.

Categories
Node.js Redis

A Redlock example with Node.js about how to lock a key pair on Redis

In the previous example we’ve tested with ApacheBench an application deployed using Kubernetes and Docker, composed by a Node.js microservice to get and set key value pairs on Redis.
We saw that if we have many concurrent requests from multiple clients we can’t know before which will be the final value of the key on Redis.

In this post we see an example about how we can lock a key value pair on Redis, so that another client has to wait before to set a new value.
We will use the Node.js implementation of Redlock, the algorithm to have distributed locks with Redis.