https://www.relaximus.com/ Recent content on Relaximus - personal blog Hugo -- gohugo.io en Relaximus Sun, 20 Aug 2017 21:38:52 +0800 https://www.relaximus.com/about/ Sun, 20 Aug 2017 21:38:52 +0800 https://www.relaximus.com/about/ Hugo is a static site engine written in Go. test1. It makes use of a variety of open source projects including: Cobra Viper J Walter Weatherman Cast Learn more and contribute on GitHub. https://www.relaximus.com/post/azure-streams-ultra-garbage-survival/ Sun, 02 Oct 2022 17:01:20 +0200 https://www.relaximus.com/post/azure-streams-ultra-garbage-survival/ Hi, here you’ll find some general thoughts about the ETL, and some special exercises solved with a pretty attractive option we can have with modern cloud providers - Azure in my case. My example is a stream of values coming from some source, to keep it simple, let’s say we are receiving timestamp and value. The stream is very dense, and we want to compress it in time and provide some other structure of payload (basically, just transform it from one JSON format to another one). https://www.relaximus.com/post/bad-news-you-are-losing-your-memory/ Sun, 15 Aug 2021 21:08:20 +0200 https://www.relaximus.com/post/bad-news-you-are-losing-your-memory/ That particular topic could be quite trivial for some of the engineers who deliver java applications as docker containers, but… If you’ve never cared about that particular thing, you’d better do it. Overwise, you will be losing a lot of memory in the container as unused. As usual the pet project for the investigation could be found here. Application for testing First, I will create a simple application exposing controller for triggering the needed load inside the application to boost the heap rise. https://www.relaximus.com/post/searching-data-from-dynamodb-with-kinesis-streams/ Fri, 25 Dec 2020 17:01:20 +0200 https://www.relaximus.com/post/searching-data-from-dynamodb-with-kinesis-streams/ This is a second part of the previous writing about the option for streaming data from Amazon DynamoDb to other services. I wasn’t aware of all options of Amazon Kinesis family services when was writing the first part. But during preparation, I noticed that this is a good alternative to the old school AWS Lambda processing, which I described in the first part. Well, what’s so interesting in this alternative is that you don’t need to bother about the connectivity to your Amazon ES from Lambda code, which was quite a tricky place, to be honest. https://www.relaximus.com/post/searching-data-from-dynamodb-in-three-simple-steps/ Tue, 08 Dec 2020 17:01:20 +0200 https://www.relaximus.com/post/searching-data-from-dynamodb-in-three-simple-steps/ It’s well known that DynamoDB works well for lookup queries. But if you need to run heavy, analytical queries against the data in the DynamoDB table, you would need to use other tools for indexing data. One of the solutions you can come across in the AWS documentation and AWS blog posts is to use DynamoDB streams to load data to the AWS ElasticSearch service for indexing and providing a reacher search possibilities to users. https://www.relaximus.com/post/four-cool-things-about-spring-actuator/ Tue, 27 Oct 2020 17:01:20 +0200 https://www.relaximus.com/post/four-cool-things-about-spring-actuator/ I am going to quickly show some cool things, which could be done almost out of the box by means of Spring Actuator module. I selected just 4 cool features, but there are of course more. Before getting started with cool things, I must warn you that big power brings also high responsibility. Don’t forget to check the security part of actuator documentation before delivering a solution to production. https://www.relaximus.com/post/functional-endpoints/ Sun, 13 Sep 2020 17:01:20 +0200 https://www.relaximus.com/post/functional-endpoints/ Not so many people, using Spring MVC consider or even know the alternative way of describing the controllers (or better say handlers) in the project. I would like just quickly show how nice and concise could be this approach, and also, what is not less important, fun. This is the main reason why we all are here, right? Spring CLI To show something, we need this “something”. Let’s quickly create the simple, sample MVC project in Spring. https://www.relaximus.com/post/spring-basics-everyone-should-know-part-2/ Sat, 20 Jun 2020 21:08:20 +0200 https://www.relaximus.com/post/spring-basics-everyone-should-know-part-2/ This is a continuing of the previous reading about the core functionality of the Spring Framework provided for types conversion. Here we’ll take a look at the concepts of Converters and Formatters. Short reminding - the project serving as a victim for the conversion executions could be found here. Converter<,> The Converter concept is a more general one, it allows you to convert data between any two types. This means that you can use not only for the web-layer for converting from String but some more general conversion logic. https://www.relaximus.com/post/spring-basics-everyone-should-know/ Sun, 14 Jun 2020 17:01:20 +0200 https://www.relaximus.com/post/spring-basics-everyone-should-know/ There are some basics that usually allow you to handle a bit more complicated abstractions on top of them. I think, in the case of Spring - the type conversions is one of such topics. I tried to structure a bit what Spring has and how we can use it in our applications. The reading may be more useful to the beginning developers with Spring, but I hope the experienced developers might find something interesting in it. https://www.relaximus.com/post/codebuild-going-out/ Mon, 11 May 2020 02:06:21 +0200 https://www.relaximus.com/post/codebuild-going-out/ An interesting question came to my mind when I was playing around with AWS Autoscaling group setup. What is actually a better, most elegant way to deploy apps in your EC2 instances, especially in the AWS autoscaling group? To be honest, I don’t know the right question, but the alternative way of doing that to just pulling it from S3 in user data I know for sure now. I am going to use the CI tools provided by AWS: CodeBuild and CodeDeploy. https://www.relaximus.com/post/how-ec2-man-saved-the-load/ Sat, 18 Apr 2020 13:58:12 +0200 https://www.relaximus.com/post/how-ec2-man-saved-the-load/ Well, I am pretty sure, that everyone who touched the AWS at least once, heard about the main service, which Amazon provides. I mean Elastic Compute Cloud or EC2. It comes with a very cool feature, which allows you to handle a peak load and at the same time absence of load too, adjusting capacity of resources and saving money in the end. I realized that I have never tried to set up this architecture myself and test how it actually works. https://www.relaximus.com/post/micronaut-vs-pure-groovy-lambda/ Tue, 04 Jun 2019 11:34:52 +0100 https://www.relaximus.com/post/micronaut-vs-pure-groovy-lambda/ “Have you seen this new serverless framework - Micronaut?” - said once my colleague. “Yea, but this is just a framework, it is not quicker than writing pure light function if in the same Groovy language.” - responded I. “Yes, but it uses AST transformation and a lot of things moved to the compile time.” - he said. This conversation was the source of the idea to compare two simple AWS Lambdas: written as a groovy class and the groovy function in Micronaut. https://www.relaximus.com/post/spring-amazon-dynamodb-local-guide/ Sun, 24 Mar 2019 19:01:52 +0100 https://www.relaximus.com/post/spring-amazon-dynamodb-local-guide/ Let’s take a look how neat and nice could be code for persisting in Amazon’s DynamoDB service using Spring data dynamodb project. Speaking of aws dynamodb, you can’t avoid to use local version of dynamodb during development cycle. So, we slightly touch this option in this tutorial. tip DynamoDb is a NoSQL highly scalable database from Amazon Web Services. The full example code of the tutorial could be found on github. https://www.relaximus.com/post/amazon-api-gateway-stage-variables/ Tue, 29 Jan 2019 23:13:48 +0100 https://www.relaximus.com/post/amazon-api-gateway-stage-variables/ As you probably know, the Amazon API Gateway could be a good replacement for the old-fashioned web application. Image from Amazon doc. This is a short example showing the API Gateway stage variables usage. This is not a deep documentation of the entire functional, which provides AWS API Gateway, but just one of many examples of particular feature. If you don’t want to complete manually the steps from this tutorial, you can just clone the already finished example from here: