January 24, 2016
It won’t be long till I’ll get my new virtual server with docker support. Right now I’m using apache with virtual hosts to redirect from different domains to different web applications. The questions arises: How can I do the redirection with web applications inside docker instances? This blog article shall document my investigations into this topic. I’ll revisit it after some hands on experience. Right now it’s just the result of web research.
Automated nginx proxy for Docker containers using docker-gen
nginx-proxy sets up a container running nginx and docker-gen. docker-gen generates reverse proxy configs for nginx and reloads nginx when containers are started and stopped.
You can find the project on github.
March 10, 2015
September 6, 2014
Creating software is not only about hacking alone for hours and creating the “perfect” solution. It should always be about sharing inside into how creating elegant and maintainable code. But what a lot of software developer will experience is that discussing about code, trying to argue about how to code with fellow software developers at work is often impossible (for a number of reasons). So should you despair? If you are intererested in this kind of thing, there is a new (maybe just for me) website/community for something exactly like this: Creating code and talk about shortcomings or clever solutions. It’s called exercism.io. And it’s stated mission sounds like that:
- There is immense value in comments and critiques of your code by your peers.
- You grow and improve your ability to write code by reading others’ code and commenting on it.
- As a better coder you help to improve the world of software development
This is the essence of Exercism.
Exercism is your place to engage in thoughtful conversations about code. Explore simplicity, idiomatic language features, and expressive readable code.
Why I like exercism.io that far:
- Easy to start
- A nice command line interface program to let you automatically submit you code
- A focus on TDD (test driven development)
March 3, 2014
If you are a getting warning messages like this one on your local developer oracle installation,
java.sql.SQLWarning: ORA-28002: the password will expire within 1 days
then there are two easy step to avoid the situation that you are not able to login with a given database user.
Step 1: Set the passsword policy to never expire passwords. Execute this SQL Query with your SYSTEM database user.
ALTER PROFILE DEFAULT LIMIT PASSWORD_LIFE_TIME UNLIMITED;
Step 2: The expiring database user accounts are not affected by the above statements. You have to set a password for them to get rid of the warning and only then is the password never expiring again. You just have to start your “Run SQL Commandline” oracle console and first connect via the sysdba user (don’t be afraid, you don’t need a password for that one).
connect / as sysdba;
When you are connected successfully, just change the password for any database user
alter user SYSTEM identified by NEWPASSWORD;
(Disclainer: I’m no fan of oracle, but in my workplace I have to use it)
October 23, 2013
IF you need to find HTML elements in a web page via XPath, it’s desirable to do this with an already existing web page in your browser. in Chrome/Chromium this is especially easy. If you open the web developer tools and switch to the console, you can type something like that
And the browser will return you the found HTML element (or nothing if it does not exist).
May 20, 2013
The video about this topic can be found on infoq.com
May 13, 2013
An interesting video busting myths about cloud computing can be found on infoq.com
Khawaja Shams presents how NASA’s JPL uses cloud computing, and evaluates some of the existing cloud computing myths in the MythBusters style.
April 30, 2012
There is an easy way to merge two or more PDF files. You can use the free software called Pdftk. You can get it via the package system of your preferred linux distribution or the homepage of the project.
Here is an example for merging threepdf files
pdftk 1.pdf 2.pdf 3.pdf cat output 123.pdf
You can find more examples on the projects website.
March 16, 2012
If you are looking for a reasonable priced mono laser printer which works flawlessly under linux: I recommend the Samsung ML series. For example the Samsung ML1860.
For more information how to install the driver, just look here: http://ubuntuforums.org/showthread.php?t=341621