mysql
Today I discovered that one of my servers mysteriously ran out of disk space. I ran the following Linux command to find all the biggest files and folders on the server: sudo du -a / | sort -n -r | head -n 100 ... and found that it was the binary logs used for
maven
Maven creates and checks MD5 checksums at various times. For instance, when downloading an artifact from a repository, Maven checks whether the checksum of the downloaded files (e.g. POM, JAR) is correct. I am uploading Maven artifacts manually to a very simple, file-based repository. This requires me to calculate
aws
Today I came across the following exception while working with the AWS SDK for Amazon Lambda: com.amazonaws.AmazonServiceException: Cross-account pass role is not allowed. (Service: AWSLambda; Status Code: 403; Error Code: AccessDeniedException; Request ID: xxx) At first I was a bit puzzled where this exception might come from; but
aws
According to a recent article on the New Stack Blog, the Amazon Serverless Team (responsible for instance for Amazon Lambda) is about to release a new open source product called 'Floruish'. Currently, there are very few details available on this product. These are some points I could find:
aws
Using bucket policies, it is easy to set ACL settings for all new objects that are uploaded to Amazon S3. However, I wanted to remove 'public' read rights for a whole bunch of objects at the same time and such policies do not apply to objects that are
JQuery UI Droppable is a great framework for implementing drag and drop features in a web application. Here I will show two ways how it can be prevented that multiple droppable elements on the same page can receive the same drop events. If the one droppable is the parent of
ec2
The most recent version of the Amazon Linux VMI (2015.09.1) seems to install version 2 of Puppet by default. However, if you need to install Puppet 3, that is also easy enough. Just type in the following to install it: sudo yum install puppet3 If any errors pop
I like to organize my files by prefixing the current date and time to the file name. Yes, sorting files by date created and date modified more or less accomplishes the same thing but I just find it to be more organized this way. I've spent countless hours
Today one of my virtual servers suddenly showed up as offline in my New Relic console (Which is an amazing tool and free by the way). I checked the log file /var/log/newrelic/nrsysmond.log and it had these contents: 2015-08-15 02:06:04.512 (915) error: nria_context_
gwt
Today I deep-dived a bit into how GWT creates and reads Serialization Policy files. These are the .gwt.rpc files which are generated beside the JavaScript files for GWT modules. Chiefly, I learned two things: * The .gwt.rpc files are only used by the server. The client never reads them.
gwt
GWT is a very useful tool to compile Java code into JavaScript. Nashorn is Oracle's new JavaScript implementation which runs JavaScript scripts in Java. In order to run JavaScript server-side code within a Java server I now want to make an extensive GWT library available to this JavaScript
javascript
The JVM is by design an insecure environment and it is generally difficult to run untrusted code in a sandboxed environment. However, it seems that is relatively easy to sandbox JavaScript code running in Oracle Nashorn. The instructions are here. Strangely, this was not easy to find through a Google
