React is JavaScript library created by Facebook. It is a tool for building UI components. In this tutorial, I am going to deploy sample react application in Google Cloud. Create react app using npm npm is a package manager for the JavaScript programming language. npm makes it easy for JavaScript developers to share and reuse…

What is Let’s Encrypt? Let’s Encrypt is a non-profit certificate authority run by Internet Security Research Group. It provides X.509 certificates for Transport Layer Security encryption at no charge. The certificate is valid for 90 days. What is HTTP? HTTP stands for Hypertext Transfer Protocol. HTTP uses TCP(Transmission Control Protocol) to send data packets between client and…

Overview Cassper is a database migration tool. It strongly favors simplicity and convention over configuration. Migrations can be written in CQL . All the CQL database syntax are supported. You can use the Maven plugin. Supported database is Cassandra. Written in Scala. Migration Cassper is supported for versioned migrations. Versioned migrations have…

When we use micro service architecture, we use lots of docker container. So we need to monitor all the containers metrics such as memory, I/O, cpu and etc. 1. What is Prometheus? Prometheus is an open-source systems monitoring and alerting toolkit originally built at SoundCloud. The main Prometheus server which scrapes and stores time…

In this tutorial, we are going to use, SpringBoot Postgres Docker Docker compose 1. Create SpringBoot Application There are several ways to create spring boot project. In here I am going to use Spring Initialiizr.

1. Single Threaded Application This is the simple java program for thread. Every java programs has at least one thread. The Main thread in Java is the one that begins executing when the program starts.

1. What is Redux? Redux is a predictable state container for JavaScript application. The state of your application is kept in a store, and each component can access any state that it needs from this store. 2. Why is Redux? Most libraries like React, Angular, etc. are built with a way for components to internally manage their state…

1) NoSQL Do not follow the traditional relational database management systems principles. ACID principles is reduced. (Atomicity, Consistency, Isolation and Durability). Atomicity- a transaction must be treated as an atomic unit, that is, either all of its operations are executed or none. Consistency- The database must remain in a consistent state after…

Elassandra integrates Elasticsearch within Cassandra as a secondary index. Elassandra = Cassandra + Elasticsearch Elassandra need more memory than Cassandra because Elassandra is using Elasticsearch. In here, you need several machines to setup multi node Elassandra cluster. In my sample, I have used three machines to setup Elassandra cluster. node 1 - 10.10.10.1 node 2…