Monday, 16 December 2013

Open Source Software is Anarchism*

There is No Governing body

People come together purely through enlightened self-interest to build something useful

Yes there are freeloaders
yes there is chaos
yes standards vary

But some amazing stuff gets built despite all that.

* Note: anarchism != anarchy... go look it up, if you've never heard of it before...

No. it wouldn't work as a form of government for obvious reasons (ie people are still people)... but that isn't the point I'm trying to make here.

Monday, 9 December 2013

In the land of the blind

In the land of the blind
the one-eyed man is burnt at the stake
for asserting the heresy of light in our land of blessed darkness

Tuesday, 3 December 2013

Twitter bootstrap - for quick and easy design

If you're anything like me, for a graphics designer you make a great web developer.

My past attempts at design have run the gamut from "geocities" to "unicorn vomit", and I've become increasingly minimalist in an attempt to rectify that

-> less design == less unicorn-puke == win!

But it still leaves my sites looking like crayon-drawn whitesites

It's a long way from there to the current industry requirements of a clean, flexible, responsive design - able to handle mega-huge desktop-monitors and tiny smart-phones alike while looking sleek and professional... and I had resigned myself to basically just not sucking too badly and hoping my sites were useful enough for people to get past the ugly-duckling look.

but now I've found bootstrap. It lets you quickly and easily build a fully-responsive all-devices-ready design with very little graphic-design nous required. From a full grid-based system (to easily build columns that will nicely collapse on smaller screens), to all sorts of components - navbars, breadcrumbs, panels, lists of linked thumbnail images... the list is pretty huge.

Don't be put off by the "oh my god PURPLE" look of their website - this is a tool worth using.

The getting started guide is where to begin.

There's a number of pre-built templates on bootply templates that even if you don't like, you can cannibalise for the various pieces you want.

You can also buy a whole bunch of pre-packaged, professional themes (for about $12 each) from WrapBootstrap to kickstart your website design. Though be aware they are mostly built on Bootstrap 2

If you're building this stuff in rails, there's a whole bunch of bootsrap-related gems - which mean you don't have to download the css/js versions of bootstrap and mix them all into your assets directory.

Ryan Bates' railscast (see below) uses seyhunak / twitter-bootstrap-rails, which seems to have a whole bunch of neat generators for quickly throwing up layouts. I prefer not mixing bootstrap's Less with the existing SASS, and so have gone for the sass-based gem: bootstrap-sass gem.

I suspect you can combine these two powers for good by using the generators of twitter-bootstrap with the sass-based assets of bootstrap-sass... but have yet to try it (let me know if you do).

There's also a great overview of rails and twitter bootstrap with a related RailsApp that goes into far more depth (I haven't had a look at that yet).

and Ryan Bates has done a railscast on twitter bootstrap basics, and a pro-only railscast: more on twitter bootstrap


Note: Bootstrap version 3 has recently been released, and a lot of the tutorials, railscasts etc are based on version 2. Bootply has a Bootstrap 3 migration guide if you want a reference to what has changed.

Wednesday, 27 November 2013

Link: loading-icon generator

Load info is a neat website that lets you generate your own loading icon.

The first page has a hypnotising array of load-icons to choose. Click on one and it'll bring up a box that lets you choose the size and colours you want and it'll generate you a customised animated gif you can use.

Tuesday, 19 November 2013

Thursday, 14 November 2013

Zen and the Art of Western Rationality

Zen seems to have, as central to its dogma, a mystery tradition. ie it makes all its teachings appear incredibly mysterious in what appears to be an effort to make it seem harder to attain - and thus weed out those not willing to work for the enlightenment it proffers.

at least this is how it seems to western thinking. I've known a number of people who have fallen into what I believe is the trap of thinking that zen actually *is* a mysterious hidden secret that can only be approached in a non-rational way...

The reality is that zen is a very good way of switching off that part of the mind that gets in the way of thinking about the things that zen teaches... however, its not the only way.

As they say in zen - zen is not the way, but it approaches the way.

ie it's a good way of starting out, but it won't get you all the way there.

and (unlike the smugness of certain woo-woo types would lead you to believe) it's not the *only* way of reaching The Way.

It's my contention that it is just as possible to work your way there, starting with traditional western rationality/philosophy.

Here's an example pulled from zen:

A teacher once said "this is my short staff. If I call it a short staff, I deny its reality, but if I do not call it a short staff, I deny its fact, so what do I call it?"

It sounds incredibly mysterious. It's a mind-puzzle that you must work out for yourself - and if you are starting from scratch, it may take years of meditation to get to an answer... or you may grasp it in a second.

This is why it seems mysterious, like a great hidden secret that must be very valuable and thus you can feel all smug about knowing...

However, this koan contains some truths which are quite easily expressed in Western rationality also, and I believe it's more valuable to share those truths than to remain "terribly mysterious".

This koan, to me, expresses the map vs territory problem.

The map is not the territory, and yet it is the territory - just not *all* of the territory. The territory is represented by the map, but it is not defined by the map. Change the map (say, pencil in a new road) and the territory will not change (the new road does not spontaneously appear). Change the territory, and the map must be changed to match or lose it's connection with the territory.

Yet the map (if properly drawn) is the territory also - that road connects to this one in just such a way. If you follow the pattern of roads on the map, you will arrive at the destination that the map says you will.

The territory contains those facts that are within the map, but it *is not* the map itself. The map contains facts which are defined in the territory. You can recognise the territory by looking at the map - but the territory is so much more. It contains trees and roof-tiles and many other things that are not in the map.

The map is not the territory, and the territory is not the map

If I look at a map of england and say that this is england I will deny the reality of england. But if I look at the map and say that it is not england, then I deny the fact that the map is of england.

The map is the territory and is not the territory

but using the map you can approach the territory, but it is not the territory.

It does and does not have "england-nature"...

To get back to the koan... the object that the teacher is holding out is a short staff - that is the fact. If he said "this is not a short staff" then he would be denying the fact of it actually being a good example of a short staff.

However - if he broke it in half (so that it was no longer a short staff), it wouldn't be like there was no longer any short staves in the world. Thus you cannot say that is is "the" short staff. Other short staves are not defined by the properties of the object in the teacher's hand.

The name "short staff" is just a reference to it... but not a definitive one. It is not the same short staff as, say another one lying on the floor over there. If I can point to each and say "this is a short staff" then you are not naming a thing, only categorising it.

Therefore if you name it "short staff" you deny the reality of it being something *more* than a short staff.

The phrase "short staff" is the map that lets us recognise "things that have the short-staff property"... but it is not the short staff itself.

Now - perhaps you got something different from the short-staff koan. If so, instead of being "all zen and mysterious" about it, I implore you to figure out what it is you've learned... and share it with the rest of us.

Thursday, 7 November 2013

Link: Awesome guides to building a functional rails app

Rails girls is a group dedicated to training up the next generation of Rails developers... who happen to be women.

They tend to run over a weekend and get women of all backgrounds (but without rails experience) to build a rails app from scratch.

They have a set of materials that is brief, but quite impressive - and if you follow them through step-by-step it's a quick tutorial on how to get a pretty decently functional Rails app off the ground.

Start with the App tutorial to get it up and running with a simple scaffold, to add some basic styling with bootstrap, and add picture-uploads with carrierwave.

Then follow the set of guides (links are at the bottom of the app-tutorial page) to get it up on heroku, to add authentication with devise, to use geocoding to add your widgets to a map, to create thumbnails for your uploaded images and more.

With just the above you can get a fairly decent rails app built for most purposes in a day or so.

Friday, 1 November 2013

Putting your heroku repo on github

When I set up a new quick-and-dirty app on heroku... I often also want to put my code up on github.

I was really surprised this simple process wasn't covered in the otherwise pretty excellent Getting started with Rails 4 post on heroku.

It's pretty straightforward, so here it is.

If you follow the instructions as per the getting started guide (above), you'll have a local git repo, and it'll be tracking the heroku remote as "heroku". which means there's no problem with using the bog standard "origin" for your github repo version.

So from there

Step 1 create a new repo on github

  1. Go to your github page eg this is the github page for me: taryneast's github
  2. Click on the "repositories" tab
  3. Click the green "new" button
  4. Give it a name and, optionally, a description
  5. Click "create repository"

Step 2 - link it to your heroku app

  1. Go to your heroku app's settings page. this will be something like:<myapp>/settings
  2. About halfway down you can add your repo-name. It'll be <mygitusername>/<mygitrepo>
  3. Click save

Step 3 - link your local repo to the github remote

  1. open a terminal in your rails app's root directory
  2. type git remote add origin<mygitusername>/<mygitrepo>.git
  3. git push -u origin master

Your heroku app is now on github.

You can continue to push to heroku with:
git push heroku master
and to github with:
git push origin master

Wednesday, 16 October 2013

Levelling up in Ruby/Rails - for free.

So, I've recently found myself back on the job market... at least I will be, but I first want to re-sharpen my skills. I've been working in legacy Rails for a while now, and I want to make sure I'm au fait with the latest and greatest the ruby+rails world has to offer.

But when I went looking for courses - there's not a lot on offer for experienced rails devs. Most rails courses are pitched at complete beginners wanting to become a rails dev. Fair enough, but what can I do to polish my existing skills?

Thankfully, some more digging produced a nice set of related online tutorials and screencasts that will get me ship-shape in no time, and for far less than I expected

NewRelic CodeSchool offer

NewRelic currently has an offer whereby if you deploy a new site with NewRelic installed, you can get a free month of CodeSchool. Now, NewRelic is an awesomely useful tool for giving you extremely useful metrics for your site. They even have a free account - and to set this all up, you can roll out a simple site to heroku (also for free) with the new_relic gem installed and away you go.

You can then sign up for a free CodeSchool account (which will give you access to the basic level free courses), and sometime in the near future - you'll get an email from NewRelic with a special promotion code to give you your free month at CodeSchool.

CodeSchool = Rails for Zombies!

So once you've got a month of code school - you can start to work your way through the courses. Starting with the simple "Try ruby" course and through their funny "Rails for Zombies" courses all the way through Rails testing and best practices and some advanced topics of Ruby.

I was happy to discover that even in the simplest ruby course there was one or two things I'd never seen before - so they're all worth the time (but you can skip ahead to the challenges if they're too simple for you).

But the courses don't just cover Ruby/Rails, they also have a series for Javascript, HTML5, CSS3 and even iOS development. Which I'll be availing myself of for the next month - and will almost certainly spring for longer until I've done them all!

From zombies to RailsCasts

I was even happier to discover, that as a "prize" for finishing the "Rails for zombies 2" course, you get one month of a Railscasts Pro account.

Now RailsCasts was where I was planning on heading next anyway - I followed RailsCasts religiously in my early years of developing Rails, and learned a hell of a lot thereby. The number of screencasts that Ryan Bates has done by now is simply staggering. They cover a huge range of topics from detailed aspects of developing Rails (eg tagging or nested forms), to most of the commonly-used tools, and it's great place to go if you want help on a particular topic. To get access to a free month of these on a pro account is wonderful icing on top of the CodeSchool month.

Other CodeSchool courses give you other freebies, and discounts on books etc too, along with lots of links to other amazingly useful resources - so my reading list has suffered a cambrian-explosion this week. I'll keep you tuned if I dig out any further fabulous free offers.

Update: you can now get 3 months of code school for free

It's a limited offer... here's a link: 3 months of codeschool

Saturday, 5 October 2013

Putting a price on your technical debt

Ben Orenstein has written an interesting article: How much should global variables cost?.

It's basically a price-list for different kinds of technical debt, and you can use it to calculate the "cost" that each of your commits adds to your codebase. By actually putting a dollar amount on each "violation" - you can get a good, visceral feel for what you're doing.

As he points out - you can still choose whether or not to keep something (sometimes you really do need to do something that would otherwise be considered a no-no), as long as you can "afford" it.

I think it's an interesting way of looking at the problem. I'd like to see you regaining points for fixing/refactoring similar code-violations out of the project too :)

Saturday, 28 September 2013

Link: don't publish your secret keys on github

I probably don't really need to tell you that it's dangerous to publish secret keys on a public website... but which key am I talking about here?

  # this one...
  MyApp::Application.config.secret_key_base = 'fb636477f014943b9cf2d202f9da4349a580fbb9521ef38d8dc0111ae933a10bfec732ce7d563a854db1663ba00af1db21d06d6764d84a88d0a6286bcd2299e2'

It's one of those things that often gets overlooked...

  rails new
  git add .
  git push


But if you're on heroku, rather than deploying to your own hosted site (where you can easily drop config files into a shared directory), how do you have a secret key?

Here's a great little gist that will show you how to set it up on an environment variable.


Don't forget, that if you put more than one of these into your .env file... you need to append to the file or you just overwrote your secret key (oops)

Further update

If you're on heroku and putting one of these environment variables into code that will be evaluated at compile-time (eg config/initializers/devise.rb for instance) you will need to switch on heroku's "compile time environment variable" option: user-env-compile or you will not even be able to deploy your site.

This feature allows your environment variables to be available during compilation of the slug (which is when things like bundler, asset-compilation etc are run)

Note that this is an experimental heroku:labs feature - so blah blah use at your own risk blah...

Friday, 16 August 2013

Gotcha: irb, multi-line strings and "Display all 309 possibilities? (y or n)"

Small thing I figured out. I was in irb and trying to copy/paste some text into a multi-line string to play with gsub, and it kept exploding halfway through and showing the message:

Display all 309 possibilities? (y or n)

instead of actually allowing me to create a multi-line string.

Turns out, irb still responds to tab-completion even if you're halfway through creating a multi-line string.

This kinda sucks if you want a string that contains tabs - but don't want to manually type the whole string (including tabs) yourself as you go along.

To fix it, I copy/pasted the text into vim and used :retab to replace the tabs with spaces before copying it back into the string in irb... its a hack, but it worked for my purposes.

Any thoughts on a better solution?

Wednesday, 7 August 2013

Link: alias vs alias_method

If you ever wondered what the difference was, this quick post by Neeraj Singh will show you the difference between alias and alias_method


  • alias_method is slightly more flexible accepting strings or symbols
  • alias_method will redefine local methods at runtime - which means you can override the aliased method in a subclass and alias_method will pick this up
  • alias will keep the original scope when aliasing - so even if you override the method in a subclass, the aliased method will refer to the parent's original method
  • alias works nicer with rdoc

Don't forget to use a comma for alias_method

Tuesday, 30 July 2013

Link: ruby-warrior : a fun way to learn a little ruby

I just came across ruby-warrior.

I can thoroughly recommend it as a couple of hours of fun diversion while picking up a few lines of basic ruby.

Its byline is:

"A triumphant quest of adventure, love & destiny all within a few lines of code."

Tuesday, 23 July 2013

Link: Your boss, the invader from Mars (or how agile transitions can become unhinged by poor buy-in)

If you've ever tried to implement an agile transition in a traditional workplace, you'll know there are many stumbling blocks - one of the greatest being that of the existing stakeholder: Your boss, the invader from Mars explains how change can and should be dealt with by both the SCRUM and kanban approaches to agile development - and how that can easily be messed up by your boss.

The case-study especially strikes a chord with my experiences, describing a shop wanting to "become more agile" but not actually implementing agile processes, instead trying to add the "agile" on top - with a rather apt simile where the agile process are described as "layered over existing dysfunctions as a sort of veneer".

The article then goes on to show various ways in which a boss who is not fully vested in the agile approach can unhinge the transition process... but also lets us learn the various lessons from that so a we can hopefully improve upon it in our own attempts.

Thursday, 18 July 2013

Gotcha: rvm and No binary rubies available for: ubuntu/12.04/x86_64/ruby-1.8.7

I'm working with a legacy rails system. We're still stuck on Rails 2.3.2 (yes really) and ruby 1.8.7 (it's better than 1.8.6 which we were on only a few months back).

I've just been given a new computer at work (finally) and it has ubuntu 12.04 - and I was trying to set it up with a rails stack. For which I can strongly recommend Ryan Bigg's howto article: Ubuntu, Ruby, RVM, Rails, and You

I got through the tutorial ok, happily installed ruby 1.9.3... but when I tried to install 1.8.7, I hit a snag.

    triton:[~]% rvm install 1.8.7
    Searching for binary rubies, this might take some time.
    No binary rubies available for: ubuntu/12.04/x86_64/ruby-1.8.7-p374.
    Continuing with compilation. Please read 'rvm help mount' to get more information on binary rubies.
    You requested building with 'gcc-4.4' but it is not in your path.

According to rvm, you can list the set of available rubies using rvm remote which gave me:

    # Rubies available for 'ubuntu/12.04/x86_64':


Now, I know 1.8.7 is ancient news, but I didn't think they'd drop support for it so entirely.

I went wandering about looking for a way to specify an older repository - perhaps the 10.04 repo would still have 1.8.7 in a useable format...

Turns out I'd just made a simple mistake, easily rectified.

The important clue was in the last line of the result for rvm install:

You requested building with 'gcc-4.4' but it is not in your path.

I'd copied a whole bunch of things across to the new 'puter, including my .zshrc file - which is what was specifying the gcc version (can't remember why). And on the new 'puter I had gcc version 4.6 but my .zshrc (copied from my previous computer) was pointing at this older version.

Because of this small mistake, rvm thought I didn't have a c-compiler. Which means that rvm wasn't able to install any rubies from source - only pre-compiled rubies - which means it was restricted to only those already pre-compiled for my platform (ie 64-bit ubuntu 12.04).


When I fixed the gcc line in my .zshrc - rvm was able to figure out how to install+compile source-code rubies - including v1.8.7

Sunday, 30 June 2013

How to shop at Ikea...

Step 1. recognise that you have a problem.
Decide that ikea has the perfect solution.

Step 2. Find a time where you know you have four hours spare (just in case), but convince yourself that you're only likely to be there for an hour or so.

Step 3. struggle for two hours through a labyrinth of perfect mini-houses and dawdling shoppers trying to find the thing you know is there somewhere... you've *seen* it the last time you were here...

Step 4. Along the way discover solutions for five other problems you'd forgotten you had. Write down prices and numbers for ALL the Things!!!

Step 5. You reach the end. Stop for meatballs.

Step 6. Spend a few minutes adding it all up on paper to discover that you'd be spending the next five pay-checks paying back the credit card debt to cover it. Cut it down to only two or three things you most need.

Step 7. Refreshed and ready. Head downstairs to pick up your things... and suddenly re-discover the kitchen section... and remember that you needed some wine glasses, and you loved that metal bowl and could do with another one... and oh! memory-foam pillows, you need a spare! etc etc...

Step 8. Get to the warehouse section and discover there's no flat trolleys, there's a queue of ten people waiting already and they're somehow closing in fifteen minutes. wait... and wait... and wait... plan the order-of-attack for hitting the aisles at a run.

Step 9. Eventually get to the first aisle... and discover you wrote down the wrong number for this item, and without it, almost all the others are useless.
Give up and decide you'll just get the original item *only*. try not to feel bad about the additional two hours of lost time spent choosing these items.

Step 10. Get to the aisle and discover that it comes in a set of *three* huge boxes. Heave them onto the trolley. Think to yourself... holy shit, I don't remember the boxes being that long... how the hell are they going to fit in the hatchback?

Step 11. navigate the trolley towards the checkout... as you try to turn it, remember that these trolleys work on hovercraft-physics, and have about the same leeway... try desperately to stop five times your own bodyweight of flat-packed MDF as it begins to slew into a pair of inattentive shoppers that are drifting about in front of you without looking... discover that the best course of action is to yell maniacally "I can't stop this thing!!!" while they stare at you in horror and clutch small children to their shaking breast.

Step 12. When you're finally waiting in the queue, remember that they do deliveries! You won't have to fit the boxes in the car after all! ... Get to the deliveries desk and re-discover that Ikea assumes that *everybody* has a house-wife willing to be there from 12-noon to 8pm for when they decide to show up... and they will *only* do next day delivery. Decide you want to keep your job, and go fetch your car.

Step 13. break a nail off and bleed profusely getting the first long box in the car... realise that even with the back seats down and the front seat far forward, it's still sticking out by 5cm... of course you knew this was going to happen.

Step 14. use the remaining shreds of your undergrad maths to figure out a topologically viable solution that will allow you to slam the hatchback closed before the carpark closes for the night... When you do, realise you have zero side-vision on your left, it's pouring with rain and pitch dark outside... hope to god that nobody does anything stupid on that side of you tonight. Decide to see the silver lining - if you die, at least you won't see it coming.

Step 15. get to the exit gates and discover that you were in the carpark for your free three hours... and 15 minutes - about the same time you spent struggling to get the boxes into the car... and for which you now owe $8.
Don't forget to drop your credit card on the ground after the *first* time the machine rejects it... apologise to the three cars behind you in time for it to reject you a second time.

Step 16. discover you have to turn left when leaving the carpark. You know this when twice your bodyweight in MDF suddenly slides off the passenger seat onto your left shoulder. Resolve to drive like a granny until you get home...

Step 17. as you continue to drive... try to repress the sinking feeling that accompanies your realisation that you don't have a trolley at the other end...

Wednesday, 5 June 2013

Gotcha: undefined method `render' for SomeTemplate

I recently had to scratch my head over a strange exception message I'd never seen before:

undefined method `render' for #<SomeTemplate:0xb17da594>

The problem was, it came with *no* application trace at all... just the usual Rails stack-trace.

I had to guess at where the problem came from by grepping for SomeTemplate in the controller-action that had exploded, and came across the following line of code:

  @template =[:some_template])

Now SomeTemplate is a model of ours, and prior to this error occurring that line of code had been:

  @temp =[:some_template])

I have a strong aversion to calling any variable "temp", because my reaction to seeing a variable called temp is to say "a temporary what?" not "oh, that's an instance of a template", and if I'm getting the wrong idea when I look at a variable name - that's an indication it should be changed.

So I renamed it...

Unfortunately, it turns out that @template is a magic variable in Rails that refers to the template to be rendered in a given controller action.

So Just Don't Do That.

The code has now been rewritten to the following, and works just fine:

  @some_template =[:some_template])

Thursday, 30 May 2013

Your Open Source Report Card

Have a look at your own Open Source Report Card. It dives into your github commits and generates a description of your coding propensities - skills and habits.

You might even find out something you never knew about yourself - apparently I'm a Tuesday tinkerer!

Here's mine for a comparison taryneast

Tuesday, 21 May 2013

Backporting "in_array" to older versions of should'a "ensure_inclusion_of"

Here's another shoulda backport I added recently. If you're still stuck using a legacy Rails system, this backport will let you use "in_array" in the "ensures_inclusion_of" Matcher.

Save it into something like: config/initializers/shoulda_monkeypatches.rb, then use it like this:

   should ensure_inclusion_of(:widget_status).in_array(Widget::VALID_STATUSES).allow_blank.with_message(:is_invalid).use_integer_test_value
  # backport the "in_array" method for the ensure_inclusion_of matcher
  # While we're at it, add allow_blank and allow_nil too
  module Shoulda # :nodoc:
    module ActiveRecord # :nodoc:
      module Matchers
        class EnsureInclusionOfMatcher
          ARBITRARY_OUTSIDE_STRING = 'shouldamatchersteststring'
          ARBITRARY_OUTSIDE_INT = -999999999

          # to initialize the options
          def initialize(attribute)
            @options = {}

          # add the method we want to allow us to pass in arrays instead of
          # just ranges
          def in_array(array)
            @array = array

          # might as well also add the allow_blank and allow_nil methods too
          def allow_blank(allow_blank = true)
            @options[:allow_blank] = allow_blank

          def allow_nil(allow_nil = true)
            @options[:allow_nil] = allow_nil

          # This is a method of my own addition to point out that the
          # test-value must be an Int, not a String... because a string can
          # evaluate to 0 which is a valid Int... which will make the test
          # pass where it shouldn't :P
          def use_integer_test_value(only_integer = true)
            @options[:use_integer_test_value] = only_integer

          # override description so it doesn't just try to inspect the range
          def description
            "ensure inclusion of #{@attribute} in #{inspect_message}"

          # override the matches method to allow arrays as well as ranges
          def matches?(subject)

            if @range
              @low_message ||= :inclusion
              @high_message ||= :inclusion

              disallows_lower_value &&
                allows_minimum_value &&
                disallows_higher_value &&
            elsif @array
              if allows_all_values_in_array? && allows_blank_value? && allows_nil_value? && disallows_value_outside_of_array?
                @failure_message_for_should = "#{@array} doesn't match array in validation"


          # provide the message-inspect method to use either array or range
          def inspect_message
            @range.nil? ? @array.inspect : @range.inspect

          # array helper methods
          def allows_all_values_in_array?
            @array.all? do |value|
              allows_value_of(value, @low_message)

          def disallows_value_outside_of_array?

          def value_outside_of_array
            test_val = @options[:use_integer_test_value] ? ARBITRARY_OUTSIDE_INT : ARBITRARY_OUTSIDE_STRING
            if @array.include?(test_val)
              raise CouldNotDetermineValueOutsideOfArray

          # blank and nil helper methods

          def allows_blank_value?
            if @options.key?(:allow_blank)
              blank_values = ['', ' ', "\n", "\r", "\t", "\f"]
              @options[:allow_blank] == blank_values.all? { |value| allows_value_of(value) }

          def allows_nil_value?
            if  @options.key?(:allow_nil)
              @options[:allow_nil] == allows_value_of(nil)



Tuesday, 30 April 2013

Enforced computer-free time

Gah - I've been computer-free for the past week, and not by choice.

My ageing macbook suddenly started to switch off... at random. This was ok for a while... but when it took four times for it to even get through the boot process - I had to take it into the Apple shop. meanwhile I finally set about getting a new desktop, and work gave me a new macbook to try and use.

I couldn't get the monitor to work on the desktop, and the macbook is too new to run the current ubuntu LTS (though I somehow managed to get 9.10 to install... but it won't find the ethernet port)...

I've finally got the desktop working (I was using the wrong video connection) but I still can't get mail to work properly (the joys of mail on a linux machine...), and my macbook is back from the shop... but the ethernet isn't working.

soooo.... still no email and it's been a week. But at least I have google now.

You realise just how dependant on something you've become when you suddenly don't have it anymore.

You also find just how stuck you can be. How do you find the location of a good internet shop if you don't have access to google to look one up? There used to be a directory-services phone number, but I have no idea what that is anymore, and of course I don't have a copy of the yellow pages anymore (who bothers with those when you have google)?

Wednesday, 24 April 2013

Ubuntu without the Unity!

For some time now my ageing (and now quite flaky) Macbook Pro has been running Lucid Lynx (an older version of Ubuntu). I've been biding my time and avoiding upgrading since, well, April 2010, I guess.

For most of the time it was because upgrading your only machine that you rely on for 100% of your income, to a potentially unstable, non long-term release version is generally a bad idea; but then, when I went to a new employer, I tried a new install of the new long term release... and slammed headlong into the weirdness that is the Unity Interface.

To sum up my experience: when I buy a desktop, I want it to *be* a desktop... not a iPad.

Now - maybe I'm just being backwards and should embrace the new unified interface which I'm told is meant to be amazing... if a little bloated.. and sometimes corrupts your file system if something goes wrong... but this is still my only machine (for now) and I need to be sure it's ok. I don't want to upgrade to Unity.

Of course, there is now a new long-term-release version, and sadly, the old one is now no longer supported, so I'm feeling a bit like a sprite in an old platform game, being relentlessly pushed towards the future by the scrolling screen...

Thankfully, I've malingered just long enough for the Ubuntu Gnome project to have been officially blessed by . it's not an LTR version yet, but it will be.

Until then - it's also possible to upgrade to the LTR but keep gnome. I've been putting it off because I'm ultra-busy and kept finding other, much more important things to do than figuring out how to do it myself... but I've just found a neat article on how to change your ubuntu interface to gnome.

Just what the doctor ordered

Friday, 12 April 2013

Huge medieval camping event - come and join in!

war at Rowany festival

The reason it's been so quiet around here this month is that I've been crazy busy in my main hobby due to our major event for the year (run by our local group).

Rowany Festival is the largest Medieval re-enactment event in the Southern Hemisphere. I've heard it described as "kind of like Burning Man but with a medieval theme" - we prepare all year for this!

This year 800 of us all got together at Peats Ridge and camped medieval-style, fought wars, sang, danced, drank a *lot* of booze (some of it made by me) and generally had a great time...

Needless to say not a lot of Ruby got written... but that'll pick up again now I've got most of my washing done and camp kit packed away again.

If you'd like to join me on this stuff - I'm the president the NSW branch of the SCA, known as Rowany. The Australian kingdom is called Lochac (and also covers NZ too).

The whole Society is huge: 100,000 worldwide, and we all run regular events (camping roughly once a quarter, and feasts/tourneys once a month and just general hanging-out and learning fun stuff every week) and it's a great deal of fun.

Come along to our casual fighter-practice which is held on Tuesday nights at Petersham Town Hall on Crystal St (near to Petersham Station). We regularly get 30-50 people every week and they're running beginners fighting classes right now*. We also have regular singing, Calligraphy fibre-craft and costuming days every month.

* its $5 a night for non-members, or you can join for a year for $30 - but you have to do your membership online here (we're not allowed to take payment directly for that)

Picture Credit: Enough Wealth: Rowany Festival

Tuesday, 5 March 2013

Link: Why Yammer believes the traditional engineering organizational structure is dead

This is a great article describing the way that Yammer has set up its organisational structure to be nimble and effective. Why Yammer believes the traditional engineering organizational structure is dead

Highlights for me:

Yammer’s biggest rule of thumb is “2 to 10 people, 2 to 10 weeks,” ... If you employ the “2 to 10″ rule, it’ll also force you to release often, test your assumptions, and not over-invest in mistakes.


While everybody knows how expensive context switching is, it’s staggering that nobody builds that into their organization as a constraint. With total focus, you build one thing, ship it, and then are able to move onto something else.

Thursday, 14 February 2013

Quick and dirty facebook feed parsing

So, there's this big discussion going on for my hobby group at the moment, and the main discussion has been going on in facebook - mainly because that's where I was first asked to set up a discussion and it took all of five minutes to get the page up and running.

However - now that discussions are progressing, there are a number of people *outside* the facebookiverse who have raised quite reasonable objections to the discussion happening there. not everyone is on facebook, not everyone *wants* to be on facebook, and to be honest, a facebook group kinda sucks for searching and archiving really important discussions.

thus it has been requested that I copy all the posts and comments to Someplace Else, to make them available for more general consumption.

At first I balked at this request - 24 posts and 250 comments to be individually copied/pasted??? Who has that kind of time?

Of course when I actually sat down to think about the problem seriously, it took far less time than I though to solve it. So here's what I did, including the quick-and-dirty ruby script that will massage the facebook feed into something that resembles readable format. It aint pretty - but it'll pass for government work.

Step 1: get the feed from the API

I'll assume you are actually a member of the group that you're after. You will need to be.

You need to go to your group and get the group's ID from the URL.

The facebook API page is here: Facebook Graph API explorer

First you need to create an access token to get the data out of facebook. This is essentially the same as doing one of those "allow application to access my data" things that you click on when you add a new app. In this stage, you need to allow the Graph-API application to access *your* group-data, to prove that you have access to he feed of the group - and to allow it to fetch out all the posts for you.

  1. click the "Get access token" button
  2. Select the "user_groups" checkbox
  3. click the new "get access token" button
  4. follow any prompts (if this is the first time using this API, you'll get the "allow access for this application" process - but it may not happen for subsequent attempts

You should now have a long encoded token in the box at the top of the page.

Next up we need to tell it what feed to use. There's a drop-down labelled "GET" which you should leave as-is. In the text-box next to that, type in the ID of the group in a URL-format like this: /1234567890?fields=feed and then click "Submit". The "fields=feed" tells the API to actually go and fetch the feed of posts and comments.

At this stage, you should be able to see a huge hash full of posts and comments in the box to the right hand side of the screen. Copy and paste that into a file.

Step 2: massage it into shape

Now you've got your feed data, you just need to play with it and spit it out into a nicer format. In our case, I decided to go for just a rough html format that showed what the posts were, what comments were attached, and who said what. My script is posted below - which can serve as a starting point for whatever you'd like to see done.

This script accepts the input filename and an optional output filename (or it just jams '.html' on the end of the input filename). It'll generate a really rough-and-ready html file that contains the posts and comments (with names and datetimes) plus some of the links (if present).


#!/usr/bin/env ruby

DATE_FORMAT = "%H:%M:%S %d-%m-%Y"

class Object
  def blank?
    self.nil? || (self.respond_to?(:empty?) && self.empty?)
  def present?

new_file_name = nil

# if they've passed in the filename, use it
if ARGV && ARGV.length >= 1
  file_name = ARGV[0]
  if ARGV.length > 2
    new_file_name = ARGV[1]
if file_name.blank?
  p "usage: facebookfeed <file_name> [<outfile_name>]"
p "got file_name of: #{file_name}"

unless File.exists?(file_name)
  p "file: #{file_name} does not exist"

# munge up an html filename for the output file
new_file_name ||= file_name.split('.').first + '.html'

if File.exists?(new_file_name)
  p "output file: #{new_file_name} already exists, please supply another"
  p "usage: facebookfeed <file_name> [<outfile_name>]"

# parse json in file into ruby - preferably a hash
require 'rubygems'
require 'json'
require 'date'
facebook_hash = JSON.parse(

feed_data = facebook_hash["feed"]["data"]

if feed_data.present?,'w') do |outfile|
    puts "parsing #{feed_data.count} posts"
    sum = 0
    feed_data.each {|post| sum += post["comments"]["count"].to_i }
    puts "with: #{sum} total comments"

    feed_name = feed_data.first["to"]["data"]["name"]

    # html headers go here
    outfile.puts "<html>"
    outfile.puts "<head><title>#{feed_name}</title></head>"
    outfile.puts "<body>"
    outfile.puts "<h1>#{feed_name}</h1>"

    feed_data.each do |post|
      outfile.puts "<p>by <b>#{post["from"]["name"]}</b> at: <b>#{DateTime.parse(post["created_time"]).strftime(DATE_FORMAT)}</b></p>"

      if post["picture"].present?
        outfile.puts "<div style=\"float:left;\"><img src=\"#{post["picture"]}\" /></div>"
      name_str = post["name"]
      name_str = "<a href=\"#{post["link"]}\">#{name_str}</a>" if post["link"].present?
      outfile.puts "<h2>#{name_str}</h2>"

      message = post["message"]
      message.each do |para|
        outfile.puts "<p style=\"clear:both;\">#{para}</p>"

      comments = post["comments"]

      if comments.present? && comments["count"].present? && comments["count"].to_i > 0
        outfile.puts "<h3>Comments</h3>"
        outfile.puts "<dl>"

        comments["data"].each do |comment|
          outfile.puts "<dt>by <b>#{comment["from"]["name"]}</b> at: <b>#{DateTime.parse(comment["created_time"]).strftime(DATE_FORMAT)}</b></dt>"
          outfile.puts "<dd>#{comment["message"]}</dd>"
        outfile.puts "</dl>"
      end #any comments present
      outfile.puts "<hr />"
    end # each post

    # html footers go here
    outfile.puts "</body>"
    outfile.puts "</html>"
  end # with open outfile
end #feed data present

Friday, 8 February 2013

Link: What rails security means for your startup

If you hadn't already heard, Rails has a security vulnerability that affects all versions of Rails. This one is about XML-parsing of YAML strings.

This was followed by a second vulnerability in the JSON parser - again of YAML-parsed code.

So what does this all mean for all of us running Rails-based systems? Is this just a flash-in-the-pan issue that will fade away the moment it's out of the public eye? or is it a herald of the coming apocalypse?

A really cogent overview of what the rails security issue means for your startup has been written by Patrick, and I strongly recommend you read it, and pass it on.

Amongst a number of useful overviews, it covers such things as "yeah, but we're not a high-profile site, nobody's going to attack us right?" and concludes that the worst may not yet be past, and that:

You Should Be At Defcon 2 For Most Of February

Saturday, 2 February 2013

Link: Help Vampires: A Spotter’s Guide

Here's a great post on the ubiquitous "Help Vampire" who drains the life out of helpful communities...

Help Vampires: A Spotter’s Guide gives tips on how to spot, avoid and reform them for the future benefit of humanity...

Sunday, 27 January 2013

XML-YAML-parsing security fix for older versions of rails

Earlier I mentioned the Serious Rails vulnerability that affects all versions of Rails for the last six years.

A fix has been put into the latest versions of Rails 2 and 3. but it requires you to upgrade to the latest version.

If you have an older version of rails and can't upgrade for various reasons (eg we are still stuck on v 2.3.2 due to some legacy code), there's a better fix for the *link* xml parsing error than the workarounds on offer (which tend to switch off your ability to parse XML).

The fix that we've done requires that you use bundler, though you could equally-well freeze rails into vendor/gems and make the same patch there. We chose the bundler/github approach because it reduces the size of our repository.

Step 1: fork a copy of rails for yourself

  1. fork rails
  2. git clone it into a local directory.
  3. checkout the *tag* that corresponds with the version you are on (eg for us: v2.3.2.1) - you can see what tags there are by running: "git tag -l"
  4. Don't worry about the big scary message it gives you about a detached HEAD - that just means you've got a specific commit checked out instead of a branch.
  5. create a branch for yourself eg for us: git branch v2.3.2_xmlfixes
  6. checkout that branch eg git checkout v2.3.2_xmlfixes
  7. push that to your repo on github with eg: git push -u origin v2.3.2_xmlfixes

Now you have a forked copy of the rails repo with a branch at the rails-version you are using that you can refer to in your Gemfile.

Step 2: actually apply the patch...

cherry-pick this commit (which if you look at github is is the one from v 2.3.15 that fixes this very error). Using:

git cherry-pick 70adb9613e4a40c5645c99da37

Note: You are likely to get conflicts with the CHANGELOG - you can keep them or just throw them away as you wish (it's just the changelog which describes the latest changes).

commit and push to your repository.

Now you have a patched version of rails in your git repository.

Step 3: update your Gemfile

Your Gemfile is likely to have a line that includes rails such as:

gem 'rails', '2.3.2'

You need to update that line to point at *your* git repository and your new branch.

The following *should* Just Work:

gem 'rails', '2.3.2', :branch => "v2.3.2_xmlfixes", 
:git =>l 'git://<your_git_repo>/rails.git'

To find the git url, you can go to your forked copy of git, look near the top of the page where it has a text-box with a git-link. Make sure you click on the "Git Read-only" button, and copy what's in the box on the right.

The branch to use is whatever you named your branch in step 5 above.

You should now be able to run bundle install to regenerate your copy of rails - and it will pull the details from your forked-and-patched copy


Unfortunately, when I used the above, it bundled correctly, but any attempt to spin up the server just caused the following error:

./script/../config/boot.rb:61:in `require': no such file to load -- initializer (LoadError)
 from ./script/../config/boot.rb:61:in `load_initializer'
 from ./script/../config/boot.rb:117:in `run'
 from ./script/../config/boot.rb:17:in `boot!'
 from ./script/../config/boot.rb:130
 from script/server:2:in `require'
 from script/server:2

Luckily the answer is in the StackOverflow question: how to use a branch in a fork of rails in a project with bundler.

First, you need to add .gemspec files into your patched copy of rails. If you're forking 2.3.10, you can copy the gemspec files from the commit Adding .gemspec files for all gems in the 2-3-stable version of rails created by the author of the above stackoverflow issue.

Otherwise you'll need ones correct for your own version. The commit above talks about generating them from the associated Rakefiles. I created them by copying the gemspec files listed in the commit above, and then just copying over the spec = Gem::Specification block with the equivalent block that is in the Rakefiles.

eg for actionpack.gemspec, I copied the actionpack.gemspec from the commit into the rails/actionpack directory in my forked copy of rails. Then I opened up rails/actionpack/Rakefile and copied the whole block of code that begins with spec = Gem::Specification into the actionpack.gemspec file, deleting the previous block from that file first.

You will know if you got the gem-dependencies wrong if you get an error like the following:

Bundler could not find compatible versions for gem "activesupport":
  In Gemfile:
    actionpack (>= 0) ruby depends on
      activesupport (= 2.3.10) ruby

    activesupport (2.3.2)

Now you have generated the gemspecs, add them to your forked copy of Rails, commit them and push the commit to your github repo.

Then you can put the following in your Gemfile:

:git => 'git://<your_git_repo>/rails.git', :branch => "v2.3.2_xmlfixes" do
  # Note: load-order is essential for dependencies
  gem 'activesupport',  :branch => "v2.3.2_xmlfixes" # this must go first
  gem 'actionpack',     :branch => "v2.3.2_xmlfixes" # this must go second
  gem 'actionmailer',   :branch => "v2.3.2_xmlfixes"
  gem 'activerecord',   :branch => "v2.3.2_xmlfixes"
  gem 'activeresource', :branch => "v2.3.2_xmlfixes"
  gem 'rails',          :branch => "v2.3.2_xmlfixes" # this must go last

Note: make sure the gems are in the order above, with rails last - otherwise you'll get something like:

Could not find gem 'activesupport (= 2.3.10) ruby', 
   which is required by gem 'activerecord (>= 0) ruby', in any of the sources.

Also note: you *must* explicitly set the branch on the git-repo line and *also8 on all the gem-lines (and they must match) otherwise bundle install will work fine, but if you try anything else you'll get the infuriating error:

git://<your_git_repo>/rails.git (at v2.3.2_xmlfixes) is not checked out. Please run `bundle install`


you should now be able to run bundle update and bundle install and it should now work.

This has been tricky to explain, and the steps are complex - if something's not clear, let me know and I'll try and make it more plain.

Monday, 21 January 2013

Link: DHH - testing like the TSA

Learning how to test is an important skill, learning what *not* to test is also an important skill. DHH shares his thoughts on this subject, with a brief article: Testing like the TSA which cuts through the "security theatre" aspect that can sometimes begin to surround our testing efforts.

There's also a long discussion on Y-combinator about the article here Hacker News: Testing like the TSA

Tuesday, 15 January 2013

Link: Why 2012 was the best year ever

So many people are on the doom-and-gloom bus - so much so that it blinds them to the spectacular, amazing things happening in the world today. New things are being created and built, and medicine is practically screaming along.

Not that this stops the doom-sayers who claim, darkly that it all comes at a heavy price, that the advances of the first world are killing the rest of the world, and that poverty and death are on the rise...

Well, pooh to that. Here's an article that explains that actually, the world is improving at a rapid pace, including all of the usual favourite doom-and-gloom topics: Why 2012 was the best year ever

Read that before you try and tell me we "shouldn't bring children into this world" or that the world isn't as good as it was back when...

Wednesday, 9 January 2013

Serious rails vulnerability - read this!

A serious vulnerability in *all* versions of rails (for the last six years) has been spotted.

In brief: complex xml-style params go through an XML-parser that will interpret based on types. "yaml" is a valid type, and that loads the YAML-parser... which instantiates any embedded classes that can include arbitrary code - leading to all kinds of injection-attack possibilities.

A general discussion of the problem, including patched versions and workarounds for old versions is available here: Multiple vulnerabilities in parameter parsing in Action Pack

A more in-depth look at what the problem entails is available here: Analysis of Rails XML Parameter Parsing Vulnerability