Scala

Spring: Reactive programming in Java

Reactive programming is a programming paradigm that promotes an asynchronous, non-blocking, event-driven approach to data processing. Reactive programming involves modeling data and events as observable data streams and implementing data processing routines to react to the changes in those streams. In the reactive style of programming, we make a request for the resource and start performing other things. When the data is available, we get Continue Reading

Hawk-Rust Series: Actuation of Raspberry Pi Camera

Raspberry Pi provides a set of GPIO (general purpose input/output) pins that allow you to control electronic components for physical computing and explore the Internet of Things (IoT).And the Camera Module is a great accessory for the Raspberry Pi, it allows users to take still pictures and record video in full HD. In this project, we have used Raspberry Pi and its camera to authenticate Continue Reading

Collection in Scala With Trait Traversable And Iterable

Scala includes an elegant and powerful collection library. They are easy to use, concise, safe fast and universal.Scala collection is systematically distinguished between mutable and immutable. A mutable collection can be updated or extended in place. Immutable collection by contrast never changes  but still you can remove add update but it will return a new collectionAll collection classes are found in scala.collection or in it Continue Reading

Kafka Broker Down, No worries ! Get Alerts!

In the previous post, we have monitored our Kafka matrices using Prometheus and visualize the health of Kafka over Grafana. Now we will set an alert, so whenever any of Kafka broker is down, we’ll receive a notification. For Kafka, a single broker is just a cluster of size one. Usually we don’t create a single broker. If a single broker is down, our Kafka Continue Reading

Getting Started with Akka Remoting

When we start with Akka we generally start with one actor system on our local machine but when we talk about the business application we can have multiple parts of an application and those part can run on different machine or node. Akka Remoting is a communication module to connect the actor system in peer to peer fashion. It also serves as the foundation for Continue Reading

Flinkathon: Guide to setting up a Local Flink Custer

In our previous blog post, Flinkathon: First Step towards Flink’s DataStream API, we created our first streaming application using Apache Flink. It was easy, clean, and concise. However, the real power of Apache Flink is seen on a cluster, where data is processed in a distributed manner, with the advantage of multi-core/multi-memory systems. So, in this blog post, we will see how to set up Continue Reading

Determine Kafka broker health using Kafka stream application’s JMX metrics and setup Grafana alert

As we all know, Kafka exposes the JMX metrics whether it is Kafka broker, connectors or Kafka applications. A few days ago, I got the scenario where I needed to determine Kafka broker health with the help of Kafka stream application’s JMX metrics. It looks bit awkward, right? I should use the broker’s JMX metrics to do this, why am I looking to application JMX Continue Reading

Realm: What and Why?

In this blog, I will be introducing the Realm along with its ecosystem and components in detail. Introduction The realm is a NoSQL based server and a client component. The components connect via a fast and efficient sync protocol. It enables real-time, connected apps and services that are responsive and performant irrespective of network status. The design of the realm is based on the principle Continue Reading

Need the Grafana slack monitoring alert? Let’s create it now.

In my previous blog, we created the first Grafana dashboard. Now in this blog, we will create our first monitoring Grafana alert. Before creating monitoring alerts, we need to add the notification channel through which we will be notified. Here, we will be adding slack as the notification channel. Slack notification channel: First, open the URL http://localhost:3000 in the browser and log in to the Continue Reading

Let’s create your first Grafana dashboard

In my previous blog, we discussed the setup of Grafana-Graphite for JMX monitoring.  Now we will create a first Grafana dashboard where we will create Grafana queries to visualize JMX metrics stored in Graphite. As we know, Grafana UI runs on http://localhost:3000/ by default so let’s open the URL in the browser with the default username and password which is admin: admin After login either Continue Reading

Knolx: Alpakka – Connecting Kafka and ElasticSearch to Akka Streams

Hi all, Knoldus has organized a 30 min session on 1st  March 2019 at 3:30 PM. The topic was Alpakka – Connecting Kafka and ElasticSearch to Akka Streams.  Many people have joined and enjoyed the session. I am going to share the slides here. Please let me know if you have any question related to linked slides or video. The slides of the KnolX are here: And Continue Reading

Route53 workflow for DNS Setup and Routing

Amazon Route53 is highly available and scalable cloud Domain Name System(DNS) web service. Amazon Route53 is fully compliant with IPv6.It is designed to give developers and businesses an extremely reliable and cost-effective way to route end users to Internet applications. You can use Route 53 to do three major functions:1. Domain Registration.2. DNS routing and 3. Health Checking. We will be majorly focusing on first Continue Reading

A Basic CRUD Application Using ElasticSearch

In our previous post Introduction To ElasticSearch, we talked about the basic terminology of elastic search and basic requests to create or delete an index, check the health status of the cluster, indices etc. In this post, we are going to talk about creating a basic CRUD application using DSL. Without waiting let’s get started. To create an application, first, create an SBT Project, add Continue Reading

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