Andreas Happe: tech

Linux: How to forward port 3000 to port 80

Another small tip: to locally forward port 80 to port 3000 use the following Linux iptables command: 1 $ sudo iptables -t nat -A PREROUTING -p tcp --dport 80 -j REDIRECT --to-port 3000 You can use this command to allow customers to connect to your locally run Ruby on Rails setup (as long as you have some port forwarding set up on your local router). I am using this to develop facebook open graph apps as the application URL (that is configured within facebook’s app controll page) cannot include a custom port (like 3000).

November 18, 2012 in linux tech rails

Postgres: Howto change owner for all tables

Just a small tip for today: when moving an RoR-application between servers the database user often changes. While it is easy to dump and restore database dums using pg_dump and pg_restore this might lead to invalid table ownerships on the new host. I’m using the following bash snippet for fixing this problem

November 11, 2012 in linux tech postgres

Moving OctoPress to Amazon S3 and CloudFront

OctoPress is embraced for its simplicity: write blog posts, save them, generate HTML pages and move those upon a web server. As no code is executed server-side every page can be cached and security risks are low. So far I’m hosting my blog on a rented hetzner root-server in Germany. While there’s no server-side security problem I’m still using a full blown server which imposes maintenance overhead on me. No peace of mind.

November 3, 2012 in tech linux rails security

A full-powered shoebox-sized Desktop

After three or four years it became time to replce my Desktop Computer with newer technology. I’ve got a first generation Intel Core i7-920 Octo-core processor: it still packs more than enough power but sadly gets too hot and thus the cooling system got too loud for my taste. So time for a new Desktop! I decided to go the miniITX route. The main idea was to pack as much power-efficient technology in an as-small-as-possible case.

October 28, 2012 in tech linux hardware

Generating PDFs with wicked_pdf

Ruby on Rails is perfect for creating web applications but sometimes you just need to create some documents which can be stored or send through email. While printing is no problem with CSS not all users are able to “save/print page as pdf”. The ubiquitous Adobe PDF file format seems to be a perfect solution for this problem. The common solution for this is Prawn (also see the RailsCast about it).

May 1, 2012 in tech development rails