lagom

Lagom Persistence API with Couchbase

Reading Time: 4 minutes In this blog, I will talk about using Couchbase with Lagom’s Persistent Entity API. And then we will see how we can query for fetching the data. We already know that Lagom handles data persistence with ‘Persistent Entity’ which holds the state of individual entities. And to interact with them one must know the identifier of the entity. So Lagom provides the support to build Continue Reading

Lagom Zero Hour: CQRS Concepts

Reading Time: 4 minutes In this blog, we will discuss CQRS and how it is different from old approaches. CQRS stands for Command Query Responsibility Segregation. The approach that individuals use for interacting with a data system is to treat it as a CRUD datastore. By this, I mean that we have a mental model of some record structure. We think about producing new records, scanning records, updating existing records, Continue Reading

The yarn of Lagom: Bye-bye Monoliths!

Reading Time: 4 minutes The Microservice architecture is in an uproar, in the industry and the business domain. The Microservice architecture tackles the drawbacks associated with the Monolithic architecture. The Lagom framework is a front-runner in the development of modern enterprise applications. This blog is the first in a multi-part series on The Lagom framework. In this blog, I’d take you through the following topics: Why Microservices and not Continue Reading

Introduction To Lagom Framework

Migrating to Lagom 1.4.x?

Reading Time: 2 minutes Hi, In this blog we will discuss some of the challenges we faced while migrating lagom version from 1.3.x to 1.4.x that can be helpful if you are thinking to migrate your lagom version. But firstly we will see the versions we should have for Scala, Play and Akka. Play and Akka Versions While migrating Play and Akka version too needs to upgrade. With Lagom Continue Reading

Transport Cinnamon Matrices From Lagom To Prometheus

Reading Time: 3 minutes Monitoring is a pain when it comes to distributed applications, and even more when you have shared or non-shared variables to monitor in your application. Here in this blog, I’ll explain two tools which can ease the monitoring efforts, one for generating metrics called Cinnamon and other to visualize them, called Prometheus. Let’s have a quick brief intro about these two – Prometheus – An open-source monitoring system with Continue Reading

Custom ErrorHandlers and Lagom

Reading Time: 3 minutes Hello everyone, it’s been quite a while now since I started working on Lagom(java) and it was only recently when I came across a scenario wherein I was required to override the ErrorHandler provided by Play in my Lagom microservice. As you all already know that Lagom is built on top of Play and Akka, so there will be times when we’ll be required to Continue Reading

4 Steps to Resolve CORS – Lagom.

Reading Time: 2 minutes Welcome All!! In this blog, we are going to discuss about the CORS issue and how it has to be resolved while working with Lagom. So Let’s begin. What is CORS? CORS: Cross Origin Resource Sharing Cross-origin resource sharing (CORS) is a mechanism that allows restricted resources (e.g. fonts) on a web page to be requested from another domain outside the domain from which the Continue Reading

A Beginner’s Guide to Deploying a Lagom Service Without ConductR

Reading Time: 2 minutes How to deploy a Lagom Service without ConductR? This question has been asked and answered by many, on different forums. For example, take a look at this question on StackOverflow – Lagom without ConductR? Here the user is trying to know whether it is possible to use Lagom in production without ConductR or not. To which the best answer that came up was – “Yes, it is Continue Reading

Circuit Breaker Panel with lagom

Reading Time: 2 minutes Up to v1.3.x, you could use circuit breaker pattern with lagom only in service descriptor usually. To apply circuit breaker to some arbitrary API you had to generally use the underlying akka circuit breaker . How to use circuit breaker with unmanaged services is explained pretty well at https://blog.knoldus.com/2017/06/15/lagom-circuit-breaker-what-why-and-how/  and if you want to poke around with the underlying akka circuit breaker you can take a look at https://doc.akka.io/docs/akka/2.5/common/circuitbreaker.html. To use Continue Reading

Exception Serializer in Lagom

Reading Time: 2 minutes In this blog, I will show you how to handle error responses from a Lagom service and convert them into well-defined exceptions using exception serializers. Suppose we have an unmanaged service in Lagom. The unmanaged service hits a target service and the success response is deserialized into a POJO corresponding to the service call. But in the case of an error response, we get deserialization Continue Reading

Persistent Read Side in Lagom

Reading Time: 3 minutes Here in this blog, we will be discussing how we can query the lagom’s microservices for retrieving data. I hope you are clear with persistent entity concepts in Lagom , if not, you can take a quick overview by going through this blog. Lagom handles data persistence by using ‘Persistent Entity’ which holds the state of individual entities, but to interact with them one must Continue Reading

Lagom: Consuming a service part-2

Reading Time: 2 minutes So here’s the situation: We are using Lagom framework to develop our micro-services and we need to consume data from other services. What should we do? Well, it’s not going to be a problem for us. Lagom provides very easy way to consume a service. The very first way to consume a service is to use the unmanagedServices parameter provided in Lagom plugin. To understand Continue Reading

Let’s dive deep into Apache Ignite

Reading Time: 4 minutes Let’s first have some basic understanding of Apache Ignite and then we will look more into its life cycle with the help of a demo application. Apache Ignite is an in-memory computing platform that is durable strongly consistent and highly available with powerful SQL, key value and processing APIs. Features : Durable Memory : Apache Ignite is based on the Durable Memory architecture that allows Continue Reading

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