Lately I’ve been installing Ruby on Rails on Windows 7, and have run into a few people trying to make my life easier. One is Sarah Mei, a wonderful member of devchix who has posted a guide for getting things running.  Hearts and bunnies and flowers for her.

Pik is a neat project for Windows that helps you switch between installed versions of ruby. I’m using the Git Bash shell (as mentioned in the guide above), so I had to do a bit of tweaking, and maybe you do too, so here goes:

For some reason the installer didn’t create my .pik/.pikrc file in my home directory, so if yours didn’t create either, this is how it should look:

#!/bin/sh
pik_path=C:\\pik

function pik {
$pik_path/pik_runner.exe pik.sh $@
[[ -s $USERPROFILE/.pik/pik.sh ]] && source $USERPROFILE/.pik/pik.sh
unset GEM_HOME
unset GEM_PATH
}

Those last two lines within the pik function are because something isn’t working in the current version and the gems aren’t being loaded when you switch versions.

Once you have your .pikrc add this line to your .bash_profile (create one if you don’t have it in your home directory):

[[ -s $USERPROFILE/.pik/.pikrc ]] && source $USERPROFILE/.pik/.pikrc

Hooray!

Another installment of Sara Beats Her Head Against Tech:

When trying to convert images from RGB to CMYK with ImageMagick, the regular command to convert:

convert original.jpg -colorspace CMYK new.jpg

worked – but the converted image’s colors looked absolutely terrible. So I downloaded some color profiles, and tried to use them:

convert original.jpg -colorspace CMYK -profile sRGB_v4_ICC_preference.icc -profile Photoshop5DefaultCMYK.icc new.jpg

which just gave me the error:

convert: color profile operates on another colorspace `icc’

Searching the internet gave me absolutely no answers on any forum. Then I noticed in the docs, the example given for using profiles when the original has no profile embedded already was:

convert rgb_image.jpg -profile sRGB.icc -profile USCoat.icm cmyk_image.jpg

Wait. Something’s missing… AHA! The -colorspace option was missing!

convert original.jpg -profile sRGB_v4_ICC_preference.icc -profile Photoshop5DefaultCMYK.icc new.jpg

Works like a champ. So, if you’re getting the error “convert: color profile operates on another colorspace `icc’,” try making sure you’re not specifying BOTH the colorspace and the profile(s).

Since the happymapper google group has been closed to posting, thought I’d toss this up here.

I posted this question to the group:

---------------------------------------------------
I have a node that looks like this:

<ItemInfo>
 <ProductVar text_id="Variable1">MyValue</ProductVar>
 <ProductVar text_id="Variable2">MySecondValue</ProductVar>
</ItemInfo>

I need both the value of the attribute "text_id" and the element value
"MyValue". I was trying to use something like what I saw in the
"current weather" example:

<aws:current-condition icon="http://deskwx.weatherbug.com/images/
Forecast/icons/cond007.gif">Sunny</aws:current-condition>
element :current_condition, String, :tag => 'current-
condition', :attributes => {:icon => String}

Which (the example) works just fine on my system. So this is the
mapping I have:

class ItemInfo
 include HappyMapper
 tag 'ItemInfo'
 has_many :product_var, String, :tag => "ProductVar", :attributes =>
{:text_id => String}
end

This does not return text_id. I can return
item_info.product_var.text_id if I use "element" in place of
"has_many", but there are always going to be multiple "ProductVar"s,
so that won't work. Whenever I try to replace "element" with
"has_many", I get this error:

undefined method `attribute_nodes' for ["text_id", "Variable1"]:Array

Ideas?
---------------------------------------------------

Well, if I’d thought this through and read the code, as suggested here:
http://railstips.org/blog/archives/2010/10/14/stop-googling/
I’d have figured this out. Since I didn’t, it took the help of both the wonderful Eric Larson and Damien Le Berrigaud to point out my epic failure to read the docs (in the nicest way possible).

Eric pointed out that what I needed was to make ProductVar its own class:

---------------------------------------------------
From: Eric Larson
Date: October 22, 2010 10:07:13 AM CDT

Hi Sara,

When I'm happymapping, I like to create a class per each element I'm
parsing, always.

Try something like this:

class Product
 include HappyMapper
 tag 'ProductVar'
 attribute :text_id, String
 content :value
end

class ItemInfo
 include HappyMapper
 tag 'ItemInfo'
 has_many :products, Product
end

- - - -

Pseudo code... but it should be very close to working.

Cheers,
- Eric
---------------------------------------------------

Which I thought was brilliant, but then realized I didn’t have the method “content” available to me because I was using the nokogiri-happymapper gem. So off to Damien I went, to ask if he could merge in the “content” method to nokogiri-happymapper, only to have him tell me:

---------------------------------------------------
You can already do that with text_node. Check the spec: it "should parse text node correctly" in happymapper_spec :)
---------------------------------------------------

So, had I just read the docs and/or the spec, I’d have figured this out. SMRT.

Thought I’d post this just in case anyone else had the same problem.

“some long test string or other”.scan(/.{15}/)

Snagged from http://snippets.dzone.com/posts/show/5621 and posted here so I can find it later.

If you ever run into this pain in the butt error, hopefully this’ll save you some time:

Installing a gem without the version works fine; installing a gem using “-v 2.x.x” or whatever version you like ends in:
spec_fetcher.rb:254: warning: getc is obsolete; use STDIN.getc instead

Guess what? RubyGems 1.3.7 doesn’t play nice with OSX 10.5.8. So downgrade to 1.3.6, or if you’re using RVM, do this:
echo 'rubygems_version=1.3.6' >> ~/.rvm/config/user ; rvm remove 1.8.7 ; rvm install 1.8.7
(assuming you are using 1.8.7 in your RVM, otherwise, use 1.9.1 or whatever)
Voila, works like a charm.

EDIT 7/7/2011: According to Mike Shaheen, the new way to do this is simply:  rvm rubygems 1.3.5

Thanks to Wayne E. Seguin for his help on irc.freenode.net #rvm (and for RVM in the first place!)

PS You may have to downgrade to 1.3.5 to get “rake gems:install” to work.

This problem drove me crazy for a while:

I did a website for recently an established webcomic and some of the old archive images were showing up in negative on some browsers, and not showing up at all in others. But it didn’t happen to all the images, and not on all browsers. I beat my head against this for a while.

When you can’t figure out what’s wrong with an image, you look at the image properties, rather than beat your head against a wall. This is what I suggest, anyway, because I didn’t do that.

They were CMYK.

CMYK images show as negative in Safari, and don’t show up at all in some versions of IE.

Yay. Great. Converted them to RGB, re-uploaded, all fixed.

After installing Ruby 1.8.7 on my shiny iMac, Textmate decided that it no longer knew where the Ruby environment was. Oh, it knew where Ruby was, and would run Ruby scripts just fine, but whenever I tried to use anything from any bundle, all I got was:

“env: ruby: No such file or directory”

Maddening.

Turns out I didn’t have a environment.plist file in my /Users/(username)/.MacOSX/ directory, and even though it worked just fine before without it, that was no longer the case.

Here’s where to get a nifty little Ruby script to build it and even stick it in the right place for you. Note, the file must already exist, so you’ll have to make a .MacOSX directory in your user directory, and create an empty file “environment.plist.”

Just in case anyone else has this problem and does not want to bang their head against the wall for an hour like I did:

When using the autocomplete plugin that uses jQuery instead of scriptaculous, you need to add a route:

map.auto_complete ':controller/:action',
     :requirements => { :action => /auto_complete_for_\S+/ },
     :conditions => { :method => :get }

As per this post by the author of the plugin, who for some unknown reason hasn’t included that step with the instructions for the plugin. (WTF?) Otherwise it just sends the request to the show action, which looks at you stupidly and replies, “Couldn’t find FileData with ID=auto_complete_for_yourfieldname”, replacing “yourfieldname” with whatever you’d actually like it to return.