Wendbaar.nl

Building a 3D printer

berl — Thu, 13 Oct 2011 20:55:51 +0000

Now the building has commenced!

I posted a live stream on the the frontpage:

(Click on the image)

Hacking on vacation

berl — Wed, 16 Feb 2011 06:42:51 +0000

I’m on vacation in New Zealand, visiting my sister (Marie-Louise a.k.a. Seven). Se happens to be engaged to a fellow Geek (Let’s call him Uan). Well, She’s more geek than us because she created the most complicated machine in the world (which we can’t even imagine to produce): a baby!

As an IT shop owner (http://queenstownhq.co.nz/) who’s always busy to satisfy his customers Uan tends to shift his “want to do projects” (because customers pay the bill right?) to the next weekend.

Because he already has a lot of the parts and of course there is a shed (all New Zealanders appear to have an shed. great inventions are made here: The world first JET powered beercooler), I offered some help. (otherwise I would ending up changing the new toddler’s diapers…..)

May I present to you: my

TODO list

DIY Touchscreen (we’re half way, more to come soon!)
Arduino hacks with Processing and OSC (I’ve got an Git Repository on Github)
- An philips Moodlight imitiation: PhilipsLed
You might think: “Dude, you’re on a bloody vacation! Go see the country!”. Yup, been there, done that! This vacation is for me to sit back and relax: I have been far too busy the last few months with working for clients. Now it’s some Leon time: do some personal interesting stuff!

I’ll keep you posted!

Automagically tagging releases in github

berl — Tue, 27 Apr 2010 17:24:46 +0000

(update: now available as a gem for capistrano)

Today at work we were discussing branching and tagging etc. to keep track of the currently deployed release on various servers. We’re working with Capistrano to do deploys.

This is a script I came up with:

Edit: refactored some errors out of it

Ralf: S3 logfile downloader and merger

berl — Wed, 10 Feb 2010 18:47:56 +0000

Today we released a new gem called Ralf, it stands for Retreive Amazon LogFiles

Download the gem at http://gemcutter.org/gems/ralf or browse the source at http://github.com/kjwierenga/ralf

Usage

Prerequirements:

An S3 account (duh)
Enable logging on S3 (use cyberduck for example)

Execution:

r = Ralf.new(:config => '/my/config.yaml', :date => '2010-02-01')
r.run

Or run it in one go:

Ralf.run(:config => '/my/config.yaml', :date => '2010-02-01')

Parameters:

:config   a YAML config file, if none given it tries to open /etc/ralf.yaml or ~/.ralf.yaml
:date     the date to parse

:aws_access_key_id      (required in config)
:aws_secret_access_key  (required in config)
:out_path               (required in config)
:out_prefix             (optional, defaults to 's3_combined') Prefix the output file

You can ommit a configuration file when you supply the required parameters :aws_access_key_id_, :aws_secret_access_key and :out_path
They take precedence over the config file

Caveats

There is no logrotation as we know it like on regular unix machines

More info: S3 Server Access Logging

TODO

CLI executable

Grouping/combinig on week/month

Credits:

This plugin is created for kerkdienstgemist.nl for processing the logfiles generated by S3.

Authors: Leon Berenschot and K.J. Wierenga

Twitter Screen Saver (a.k.a. a “Stream Saver”)

berl — Thu, 14 Jan 2010 10:54:03 +0000

Just a quick and dirty experiment: A Twitter ScreenSaver.

With the Apple Developer Tools installed, you are able to create your own screensavers with Quartz Composer.
(I’ve been experimenting with this tool a few years ago when it was called PixelShox. Later it was bought by Apple to include it in Quicktime.)

This “StreamSaver” is still a work in progress and sorry; OSX 10.5+ only.

If you have any idea’s, lemme know!

Download/see it here, and place it in ~/Library/Screen Savers.

Prediction: “Twitter App Formatting Standards War”

berl — Fri, 08 Jan 2010 13:39:07 +0000

Well…, a war is a little bit exaggerated. But consistency is the issue here, which remembers me the early days of different implementations of webbrowsers (which is still a pain in the ass, ask any random webdeveloper)

For example, today I ran in to the formatting of an URL. In tweetdeck it’s only clickable when an URL has the protocol attached to it (http://). So I complained about it, thinking that people didn’t understand linking in tweets.

Turns out I was wrong, apps like tweetie and the webinterface of twitter itself automagically create a hyperlink from an address prefixed with www without an http://.

So my question is, should there be a standard (like HTML/CSS) or developer guidline to format tweets (or is there one already?)

Sending prawn documents with ActionMailer

berl — Thu, 17 Dec 2009 08:32:18 +0000

Problem: How to send a prawn pdf wich normally is generated by a controller.

and keeping it DRY

Required: Prawn & prawnto

first: Make your prawnto settings global with an initializer

^?Download prawnto_globals.rb

PRAWN_DEFAULT_STYLES = {
  :page_size   => 'A4',
  :inline      => true,
  :left_margin => 50
}

second: create a ActionMailer

./script/generate mailer recipient_mailer invoice

third: edit the generated recipient mailer (note: because I’m using the views from the controller I’ve removed the autogenerated invoice.erb. Otherwise these will be included as well)

^?Download recipient_mailer.rb

# Include (optional) controller helpers
class Prawn::Document
  include PdfHelper
end
 
class RecipientMailer < ActionMailer::Base
  # explicitly require prawn, so we get all the goodieness
  require 'prawn'
  require "prawn/format"
  require "prawn/layout"
 
  def invoice(ledger_item)
    subject    "The subject"
    recipients '"Name" '
    from       '"Name" '
    sent_on    Time.now
    content_type    "multipart/mixed"
 
    # the templates live in RAILSROOT/app/views/documents
    # these are views normally generated by the DocumentsController
    part(:content_type => "multipart/alternative") do |alternative|
      alternative.part "text/plain" do |p|
        p.body = render_message("documents/show.txt", :ledger_item => ledger_item)
      end
 
      alternative.part "text/html" do |p|
        p.body = render_message("documents/show.html", :ledger_item => ledger_item)
      end
    end
 
    # And here is the magic:
    # probably could be refactored, but it's working!
    attachment "application/pdf" do |a|
      a.filename = "#{ledger_item.period}.pdf"
 
      template = File.open(File.join(Rails.root, 'app', 'views', 'documents', 'show.pdf.prawn')).read
 
      pdf = Prawn::Document.new(PRAWN_DEFAULT_STYLES);
      pdf.instance_eval do
        @ledger_item = ledger_item
        eval(template)
      end
 
      a.body = pdf.render
    end
 
  end
end

RER2009 Rumble

berl — Sun, 08 Nov 2009 11:55:20 +0000

We (@kjw and @leipeleon) participated in the RubyEnRails Rumble last weekend. It was a blast!

Prevent spambots from posting

berl — Thu, 17 Sep 2009 22:15:46 +0000

Just got a report that we’re getting spammed by a spambot.

Then I recalled a remark @smeevil made about a technique he used to fight off spambots: create a valid form element but put it away somewhere off screen (a hidden field won’t probably work)

table.rb:

^?Download table.rb

class Table < ActiveRecord::Base
  attr_accessor :company
  validates_length_of       :company,  :maximum => 0, :allow_nil => true, :message => "Don't spam us, OK?"
end

# new.html.erb:

<%= error_message_on :abuse, :company, {
	:prepend_text => "",
	:append_text => "",
	:css_class => "flash"
} %>

<% form_for @table do |f| %>
  <%= f.text_field :company, :class => "your_company"%>
  <%= f.label :real_field %>

  <%= f.text_field :real_field %>
<% end %>

# site.css

^?Download site.css

.your_company {
 position: absolute;
 top: -1000px;
 left: -1000px;
}

Using github on the mac for non-programmers

berl — Mon, 22 Jun 2009 13:30:20 +0000

A quick and dirty tutorial for some friends of mine.

Needed software:

git-osx-installer: Full native OSX git client.

Nice to have:

Textmate: text editor.
GitHub account (for push rights).
GitX: Grapichal tool for commiting to local repo (OSX 10.5+).

Create account on github

Go to http://github.com for an account.

Optional: Provide an SSH key for pushing changes.

Clone a Repo

My advice is to generate a special dir for the projects (mine is Rails).

Fire up the terminal and type:

^?View Code SHELL

    # Goto the dir
cd ~/Rails
    # if the repo is read only:
git clone git://github.com/LeipeLeon/facebooker.git
    # if you have push rights:
git clone git@github.com:LeipeLeon/facebooker.git
    # if you installed GitX (as mentioned above)
gitx

Adding changes

With the gitx program it’s easy to commit thanges to your local repo. When these are ready to commit to the master you sync it first with the HEAD and then push your changes.

^?View Code SHELL

    # get changes from the master repo to your local repo
git pull
    # push your changes
git push

Additional info:

If it’s a rails application you’re cloning, startup the server with

^?View Code SHELL

    # Copy database credentials, uses sqlite3 as default
cp config/database.yml.example config/database.yml
    # install required gems
rake gems:install
    # make tables
rake db:migrate
    # startup server at http://localhost:3000
script/server

and you will be able to use the application at http://localhost:3000

Wendbaar.nl

Building a 3D printer

Hacking on vacation

TODO list

Automagically tagging releases in github

Ralf: S3 logfile downloader and merger

Usage

Parameters:

Caveats

TODO CLI executable Grouping/combinig on week/month

Credits:

Twitter Screen Saver (a.k.a. a “Stream Saver”)

Prediction: “Twitter App Formatting Standards War”

Sending prawn documents with ActionMailer

Problem: How to send a prawn pdf wich normally is generated by a controller.

RER2009 Rumble

Prevent spambots from posting

Using github on the mac for non-programmers

Needed software:

Nice to have:

Create account on github

Clone a Repo

Adding changes

Additional info:

TODO

CLI executable

Grouping/combinig on week/month