//carlosleon.info/Recent content on Carlos LeónHugo -- gohugo.ioSun, 31 Jan 2021 15:04:44 +0200//carlosleon.info/hg/karabiners/Sun, 31 Jan 2021 15:04:44 +0200//carlosleon.info/hg/karabiners/TLDR: Buy a Stainless Steel karabiner with a strain rate of at least 2.5kN When was the last time that you changed your karabiner? And why did you change it? Is it because it’s been two years? is it because you dropped it and you’re not sure anymore about the integrity of the device? How long as it been since the last time you changed your karabiner? How about the one that attaches the rescue to the harness?//carlosleon.info/blog/ceph-data-corruption/Sun, 23 Feb 2020 13:53:05 +0000//carlosleon.info/blog/ceph-data-corruption/The first thing I want to say is: I’m really sorry that you have arrived to this post. Most likely you are facing data corruption problems in Ceph and are looking for an answer than can help you recover your precious data. I have some news for you: this post might or might not help you. I’m sorry. May the force be with you. Data corruption in Ceph: how come?//carlosleon.info/blog/intro-to-qemu/Mon, 03 Feb 2020 00:23:05 +0000//carlosleon.info/blog/intro-to-qemu/Through my whole career and also during my studies I have always resorted to VirtualBox for my personal virtualization needs and VMWare for my customers’. Qemu has been under my peripheral vision for a few years now but since I was always happy with VirtualBox I hadn’t really had a need to look somewhere else. So, I’m still happy with VirtualBox but I now want to give Qemu a try, so here are my findings.//carlosleon.info/blog/scaleway-storage-solutions/Wed, 15 Jan 2020 00:20:58 +0000//carlosleon.info/blog/scaleway-storage-solutions/I’m currently evaluating the different storage solutions that Scaleway has to offer since I want to setup a Nomad setup for running several of the services listed on awesome-selfhosted. Specs The machine that I’m going to be working with has the following characteristics: |--------|--------------------| | Image | Debian Buster | | Region | AMS1 | | Cores | 4 x86_64 | | RAM | 12GB | | Disk 1 | 25GB NVMe | | Disk 2 | 25GB Block Storage | |--------|--------------------| The file system on the disks is ext4.//carlosleon.info/blog/homeassistant-mqtt-register-device/Thu, 09 Jan 2020 00:00:00 +0000//carlosleon.info/blog/homeassistant-mqtt-register-device/The example that we are going to be looking at is a light hooked up to an ESP8266 module (which comes with native support for mqtt) and turn that light on & off via Homeassistant. I make heavy use of Docker since it’s the easiest way I know to get started with running Homeassistant and mqtt locally. This is how you do it! Getting Started Folder structure We are going to store the Homeassistant configuration in the following directory://carlosleon.info/blog/portable-pipelines/Thu, 21 Mar 2019 00:00:00 +0000//carlosleon.info/blog/portable-pipelines/Portable Pipelines Let’s begin by making sure we are all on the same page: One day a developer starts working on a project that will transform business requirements into working features written in code. This code will eventually be backed up in a source control management system. These days git seems to be the contendant that won the race. Once that code has been pushed (speaking in git terms here) all you should want to do is to sit back and see that code be: 1.//carlosleon.info/talks/the-future-is-now/Wed, 15 Nov 2017 12:00:00 +0200//carlosleon.info/talks/the-future-is-now/ Let’s talk about the evolution of the software industry, the delivery processes from the past, the present and the future. Presented at: DevOps Pro Moscow 2017 Slides The slides can be found here. Videos DevOps Pro Moscow 2017//carlosleon.info/hg/every-sled-ride-counts/Tue, 30 May 2017 22:25:13 +0200//carlosleon.info/hg/every-sled-ride-counts/A year ago I went on my first hang gliding trip to the mountains together with the Zenith Aventura hang gliding school from Spain. We went to the French alps. We visited and flew places like Annecy, Col du Sapenay, St. Hilaire, Chamonix and some others that I can’t remember anymore. Back then we were just squabs about to leave the nest but not just yet. Our instructor had us throughout the whole trip doing morning and afternoon flights.//carlosleon.info/hg/first-thermal-flight-ever/Mon, 22 May 2017 23:06:10 +0200//carlosleon.info/hg/first-thermal-flight-ever/I have been waiting for this moment since the very first hang gliding lessons that I took back in March 2015! I know, it’s been three seasons all together and not a single time did I get the chance or the permission from my instructors to turn a circle around some raising air. So far all my flights (about 80 on the winch and 20 on the mountains) had been sled riders.//carlosleon.info/hg/season-2017-is-open/Sun, 21 May 2017 21:21:42 +0200//carlosleon.info/hg/season-2017-is-open/It’s been too long! It’s been exactly one year since my last mountain flight. Last time was a lovely 9-days trip to the French Alps with [Zenith Aventura] hang gliding school. It was my first group hang gliding expedision and boy was it fun. Unfortunately I didn’t get to fly much more after that. C’est la vie. Now I’m back in the game and the season has officially started for me.//carlosleon.info/about/Wed, 12 Apr 2017 18:21:13 +0200//carlosleon.info/about/Cloud Expert & Public Speaker based in Amsterdam, The Netherlands. Moving to the cloud is a critical process that requires lots of preparation. Without the proper strategy, your project is most likely to fail. From the technical challenges to the cultural aspects of these transformations, I help small, medium and large organisations to create a solid plan and execute it smoothly, guaranteeing the success of your transition to the cloud!//carlosleon.info/talks/introduccion-a-los-schedulers/Sat, 25 Mar 2017 15:54:45 +0200//carlosleon.info/talks/introduccion-a-los-schedulers/La coordinación manual de recursos es un proceso lento y propenso a fallos. El mercado ofrece diferentes tecnologías de punta para resolver este problema pero ¿cuál de todos escoger? ¿por qué? En esta charla hago una introducción a los principales sistemas de coordinación de recursos que hay en el mercado (Kubernetes, Mesos, Docker Swarm y Nomad). Presented at: ScaleConfCo 2017, Medellín, Colombia Slides The slides can be found here.//carlosleon.info/talks/from-dev-to-prod-in-5-minutes/Thu, 17 Nov 2016 15:31:38 +0200//carlosleon.info/talks/from-dev-to-prod-in-5-minutes/While doing my job as a consultant at Container Solutions I quickly learnt that even though companies want change, as in, they want to adopt agile softwate development methodologies, DevOps, Containers, Orchestrators, etc., they simply are not ready for such a pace. From lack of technical know-how to critical cultural challenges, they ignore what the road up ahead looks like and what they have to do to embrace these transitions.//carlosleon.info/talks/microservices-infrastructure-with-terraform-consul-and-vault/Thu, 08 Sep 2016 15:31:38 +0200//carlosleon.info/talks/microservices-infrastructure-with-terraform-consul-and-vault/Together with Container Solutions and Cisco, we built a robust infrastructure specialised in the delivery of microservices. Three key components of this infrastructure were Terraform for building the infrastructure, Consul for service discovery and Vault for managing secrets. In this talk I explain the product we built and how it all glues together. Presented at: HashiConf 2016, Napa, California, USA Video Slides The slides can be found here.//carlosleon.info/talks/writing-your-own-terraform-provider/Thu, 07 Apr 2016 15:10:47 +0200//carlosleon.info/talks/writing-your-own-terraform-provider/While working for a customer at Container Solutions I got the opportunity not only to introduce Terraform to one of their critical infrastructure processes reducing a deliverable that normally would take 2 weeks into a 30 minutes Terraform run, but also to write two Terraform providers. In this talk, preceded by a blog post about the same topic, I explain step by step why would you and how could you write your own Terraform provider.//carlosleon.info/talks/defining-your-infrastructure-with-code/Mon, 11 Jan 2016 15:10:47 +0200//carlosleon.info/talks/defining-your-infrastructure-with-code/A short introduction to Terraform, a tool for defining your infrastructure as code. Presented at: HashiCorp User Group Amsterdam, The Netherlands Slides The slides can be found here.//carlosleon.info/blog/calling-a-method-defined-in-another-file-in-go/Thu, 03 Sep 2015 00:00:00 +0000//carlosleon.info/blog/calling-a-method-defined-in-another-file-in-go/If you have two files in Go that look like this: a.go package main func main() { println(foo()) } b.go func foo() string { return "Hello, foo!" } If you go build . the project, it completes without errors and the binary file is generated: $ ls -l a.go b.go foo And it works: $ ./foo Hello, foo! But when you’re developing you want to run the project right from Go instead of compiling and then running the binary.//carlosleon.info/blog/angular-sinatra-html5mode/Fri, 13 Sep 2013 00:00:00 +0000//carlosleon.info/blog/angular-sinatra-html5mode/Sinatra, AngularJS and HTML5Mode The Sinatra Part get "/*" do File.read(File.join("public", "index.html")) end Put this at the bottom of your application file and this will serve your AngularJS application at any endpoint. This, of course, will read the public/index.html file every time that you head that endpoint. Better if you memoize it. get "/*" do render_index end def render_index @index ||= File.read(File.join("public", "index.html")) end Important note Any other route that you register after this snippet won’t be triggered as "/*" matches everything.//carlosleon.info/blog/cookies-with-curl/Fri, 13 Sep 2013 00:00:00 +0000//carlosleon.info/blog/cookies-with-curl/If want to consume an API that uses sessions using cURL, then probably you will need to make use of cookies. Using cookies with cURL is pretty simple. I’m going to create a simple web application using [Sinatra] for the example’s sake: require "rubygems" require "sinatra" enable :sessions get "/" do session[:user] # Return whatever stored in session[:user]. end post "/" do session[:user] = params[:user] # Set session[:user] to whatever sent on param.//carlosleon.info/blog/generating-json-in-go/Fri, 13 Sep 2013 00:00:00 +0000//carlosleon.info/blog/generating-json-in-go/Say you have a custom type defined like this: type User struct { id int email string age int married bool } Using the encoding/json package from the standard library to serialise an instance of a User would look something like this: package main import ( "encoding/json" "fmt" ) func main() { u := User{1, "john@doe.com", 33, true} uJSON, err := json.Marshal(u) if err != nil { fmt.Printf("Something went wrong: %s\n", err) } else { fmt.//carlosleon.info/blog/js-events-pool/Thu, 22 Aug 2013 00:00:00 +0000//carlosleon.info/blog/js-events-pool/If you’ve lately worked with mainstream SPA frameworks (Angularjs, Emberjs, Backbonejs) and related, you should know by now that things are kept in sync thanks to data binding. It’s a pleasure because (with some luck) you just need to setup your bindings and views and data models would automatically be kept in sync. Now, if you are working with a simpler application (that may not require any framework) but you would like to have some binding still you don’t want to load any framework to your project just because you want some binding here and maybe there.//carlosleon.info/blog/improving-my-sites-performance-part-2/Mon, 01 Jul 2013 00:00:00 +0000//carlosleon.info/blog/improving-my-sites-performance-part-2/A couple of weeks ago I decided to internally improve my website. Here I explain exactly what is it that I did to do so. Some of these changes include ruby memoize/memoization and Sinatra Caching. As I previously mentioned, my blog’s architechture is inspired in [@cyx]’s personal website. However, I was not totally comfortable with the fact that everytime that a page was requested (a blog post in this case), the application had to go to disk, bring the blgo post, parse the markdown and then render the view.//carlosleon.info/blog/improving-my-sites-performance/Sun, 24 Mar 2013 00:00:00 +0000//carlosleon.info/blog/improving-my-sites-performance/When I decided to finally come up with a blog, I gave Jekyll and Octopress a try. Nice plugins, “easy” deployment strategies and what not, but somehow I could not cope with them. That’s why I decided to write my own. At last I am a software developer and building a semi-static website shouldn’t be that complicated. The solution I came up with is inspired by @cyx’s personal website, although now I seriously am thinking about refactoring a couple stuff here and there.//carlosleon.info/blog/backbone-js-best-practices-for-n00bs/Thu, 31 May 2012 00:00:00 +0000//carlosleon.info/blog/backbone-js-best-practices-for-n00bs/The other day I was looking for some Backbone.js tutorials on the internetz, something that could give me some clue about how to properly structure a web application using this framework and I found a not that old (one year and a half now) blog post talking about how to do a trivial Backbone.js application. A professor at college told me once that the best way to learn to write good code is reading good code.//carlosleon.info/blog/method-stub-with-minitest/Thu, 24 May 2012 00:00:00 +0000//carlosleon.info/blog/method-stub-with-minitest/MiniTest is a testing tool that provides the necessary resources to make your test suite a complete stack, supporting TDD, BDD, mocking and benchmarking. It comes by default with Ruby 1.9.x and is also available for Ruby 1.8.7. It provides two styles of testing: Unit tests and Specs. I personally prefer Specs since they are easier to read. Find out more about this on the documentation site. If you’re not yet using it, I suggest you to give it a try.