Inject SSH pub key to Vagrant image

Usually if you create a Vagrant VM an insecure private key gets injected into the VM, which is located at ~/.vagrant.d/insecure_private_key. In Ansible you can reference that key to ensure a passwordless login to the VM. Since Vagrant 1.8.5 this doesn’t work anymore, because of security reasons. That’s why I use now this shell provisionerContinue reading “Inject SSH pub key to Vagrant image”

Setting up a Server for Ansible

Ansible is a great tool for automation and configuration management. Maybe you heard already about Chef and Puppet. Ansible is in the same field, but with a much simpler approach. The big advantage of Ansible is that you don’t need a central master server for it and you don’t need to install an “Ansible” clientContinue reading “Setting up a Server for Ansible”

Ubuntu enforce memory freedom

Sometimes it occurs that a device runs full with memory. Simply deleting the files on the device doesn’t help. Ubuntu stills shows that the device is 100% full, even if there are no files on it anymore. This command usually helps to give free the memory. sudo tune2fs -m 0 /dev/sda5 If it doesn’t helpContinue reading “Ubuntu enforce memory freedom”

Java HTTP Request with Basic Auth

This is how you do a simple HTTP request with Java. These code performs the actual HTTP request and saves the response in a String variable. If the HTTP server requires Baisc Auth this code will fail. To make it work for Basic Auth these 3 additional lines are required. The whole method looks likeContinue reading “Java HTTP Request with Basic Auth”

MongoDB Map & Reduce with Date filter

We are using MongoDB as primary DB at VersionEye, together with MongoID. Software package is a document in the “products” collection. These products collections has a subcollection with “versions”. Assume we want to know how many versions/artifacts existed for a given language to a given time? That is not a simple query in MongoDB. ThisContinue reading “MongoDB Map & Reduce with Date filter”

How to get notified about out-dated dependencies in build.sbt?

Scala SBT is the build tool for the programming language Scala. You can specify your project dependencies in the “build.sbt” file, similar to the pom.xml file in Maven. A build.sbt file can look like this. But how do you get notified about new versions of your dependencies? VersionEye now supports Scala SBT. VersionEye can monitorContinue reading “How to get notified about out-dated dependencies in build.sbt?”

Facebook Share Link

Let’s say you have an awesome social network, a dating platform for cars, and you want to share your cars profile on Facebook. It should look like this. How do you do that? First of all you should load Facebooks JavaScript SDK. Insert this code below the “body” tag in your page. Replace 99999999999999 with yourContinue reading “Facebook Share Link”

Global Variables with Ansible

Ansible is a great tool for IT automation. It’s similar to Chef and Puppet, just better!  I wrote here already an introduction to Ansible. In Ansible you have roles and playbooks. A playbook can contain several roles. Inside a role you can have tasks, files, handlers and variables. But sometimes you want to use aContinue reading “Global Variables with Ansible”

Geek2Geek at Wikimedia Deutschland

Tomorrow I’m organizing again a Geek2Geek in Berlin. The topic this time is “NoSQL Ring Architecture”. Famous implementation are Cassandra and RIAK. We will have talks to both of them! The event is hosted by Wikimedia Germany in Kreuzberg.  We will have free Beer and Pizza, thanks to our sponsors. Check out the MeetUp page and signup forContinue reading “Geek2Geek at Wikimedia Deutschland”

What is maven-compat ???

What is the maven-compat project? I was wondering. So I went to the official page of the project and found this:  Maven2 classes maintained as compatibility layer.  That is not very helpful! I would like to have a little bit more information! So clicked on the “Project Summary” link and got this.  All right. SomeContinue reading “What is maven-compat ???”

Requirements for the perfect Crowd Software Testing Tool

The StartUp testCloud – a crowd software testing provider based in Berlin – is offering a service fro crowd software testing.  Now they are working on a new Crowd Software Testing Tool, which is completely self-service. They prepared a 3 min survey to get known your needs for the perfect Tool: Everybody who finishes theContinue reading “Requirements for the perfect Crowd Software Testing Tool”

PDFKit – invalid byte sequence in US-ASCII

I’m using PDFKit at VersionEye to generate the PDF invoices. It’s a really awesome project. The idea behind PDFKit is that you generate the documents as HTML and CSS and then convert it to PDF. That works really well. Generating a PDF works like this: The first parameter “html” is the HTML as string. InContinue reading “PDFKit – invalid byte sequence in US-ASCII”

Introduction to Ansible

Ansible is a great tool for IT automation. I’m using Ansible to manage the whole infrastructure for VersionEye. Currently I have 36 roles and 15 playbooks defined for VersionEye. I can setup the whole infrastructure with 1 single command! Or just parts of it. I even use Ansible for deployments. Deploying the VersionEye crawlers into the Amazon CloudContinue reading “Introduction to Ansible”