Migrating to Snow Leopard for Rails Development

As always happens when upgrading or installing, it seems, I did run into a few problems.

Errors and Workarounds

Problem: Git doesn't want to install.

Error:

ld: warning: in /opt/local/lib/libiconv.dylib, file is not of required architecture

Workaround:

MacPorts is to blame. To uninstall MacPorts, use

sudo rm -rf \
/opt/local \
/etc/manpaths.d/macports \
/etc/paths.d/macports \
/Applications/DarwinPorts \
/Applications/MacPorts \
/Library/LaunchDaemons/org.macports.* \
/Library/Receipts/DarwinPorts*.pkg \
/Library/Receipts/MacPorts*.pkg \
/Library/StartupItems/DarwinPortsStartup \
/Library/Tcl/darwinports1.0 \
/Library/Tcl/macports1.0

(Thanks, Simon Engledew)

Problem: MySQL gem doesn't install.

Error:

ERROR: Failed to build gem native extension mysql

Workaround:

Make sure you installed the latest version of MySQL, the MySQL Preference Pane, and that you started the MySQL server before trying to install the gem. iCoreTech has directions for installing MySQL and MySQL gem on Snow Leopard.

Other Options

HiveLogic has another method for installing Git on Snow Leopoard. I was having trouble with the package installers, and doing it "by hand" via HiveLogic's instructions worked well.

My project uses RMagick. RMagick's DMG installer wouldn't work for me either. I was able to install RMagick from source using a script from OnRails.org.

svn+ssh://user@host/repos

you'll likely get an error such as

svn: Expected FS format '2'; found format '4'

which means that you're repository was created in a newer version of SVN than the version you run when you call svn+ssh. Using Jeremy's instructions results in two versions of Subversion being available on your server - one in /usr/local and one in /opt/subversion. In order to use the one in /opt/subversion (the newest one) through an SSH tunnel, you need to make some SSH configuration changes on your server.

Getting svn+ssh to work requires:
1. Set (or uncomment) PermitUserEnvironment Yes in /etc/sshd_config (on server)
2. Add PATH=/opt/subversion/bin:$PATH to ~/.ssh/environment (on server; may have to create the environment file)
3. restart SSH (on server) with sudo /sbin/service ssh stop and sudo /sbin/service ssh start
Ta da!

Thanks for the jumpstart, Jeremy!

I have a form with text box inputs for dateDepart and dateReturn. This code takes those inputs, turns them in JavaScript dates, compares them to each other and to today, and returns alerts or submits the form, depending on how the comparisons shake out.

Here's my code:

// check to make sure Return date is after Departure date, and both are after today
if ( (the_form.dateDepart.value !="") && (the_form.dateReturn.value !="") )
{
	var strFromDate = the_form.dateDepart.value;
	var dayPartFromDate = parseInt(strFromDate.substring(3,5),10);
	var monPartFromDate = parseInt(strFromDate.substring(0,2),10);
	var yearPartFromDate = parseInt(strFromDate.substring(6,10),10);
	var dtDepart = new Date(yearPartFromDate, monPartFromDate-1, dayPartFromDate);

	var strToDate = the_form.dateReturn.value;
	var dayPartToDate = parseInt(strToDate.substring(3,5),10);
	var monPartToDate = parseInt(strToDate.substring(0,2),10);
	var yearPartToDate = parseInt(strToDate.substring(6,10),10);
	var dtReturn = new Date(yearPartToDate, monPartToDate-1, dayPartToDate);
	var now = new Date();
	var today = new Date(now.getFullYear(),now.getMonth(),now.getDate());	

	if(dtDepart > dtReturn)
	{
		alert('Departure date must be before return date. Please fix and resubmit.');
		return false;
	}
	else if (dtDepart < today)
	{
		alert('Departure date must be after today. Please fix and resubmit.');
		return false;
	}
	else
	{
		the_form.submit();
	}
}

Turn User Input into a JavaScript Date
To turn the user's input into a Date, I needed to parse the input and then pass the pieces to the Date() function.

The JavaScript substr function syntax I used corresponds to dateToChange.substring(start,finish). My users are mostly in the U.S., and they enter dates in the form MM/DD/YYYY, e.g., 03/14/2009. JavaScript starts counting at 0, so the substr functions above grab "14" for the day, "03" for the month, and "2009" for the year and then pass those substrings to the Date()function to be converted in a Date JavaScript understands.

getFullYear(); returns a four-digit year such as "2009" that makes it easy to compare to the default version of today's date that
var now = new Date();
var today = new Date(now.getFullYear(),now.getMonth(),now.getDate());
gives.

Why monPartToDate-1? Remember, JavaScript starts counting at 0, so January is month 0, and December is month 11. That means I need to subtract 1 from what my user entered to get the right month for JavaScript.

Compare Dates
I needed to compare the two dates the user entered to make sure she had departure first, then return. Once I have converted both her inputs to JavaScript dates, the comparison uses a simple "greater than" operator: dtDepart > dtReturn

Calling the Date-checking Function
You'll notice my code doesn't include a function declaration; that's because this date-checking procedure is part of a larger function to validate my form. You could wrap this code in a function declaration such as
function checkDates(the_form){}

In order to call the code when the user submits the form, I like to use something like

<input id="search" onclick="checkDates(this.form);" type="button" value="Submit Form" />

in the HTML.

1. A flight search engine that searches flights from multiple destinations to one.  I want to use this when planning trips with my family and friends.  We don't all live in the same place.  We'd like to get together.  This seems like a pretty common task (e.g. national holidays, girls' weekend, bachelor parties, etc.).  I shouldn't have to search each person's flight independently and then hope that the one around the time of everyone else's doesn't sell out or go up in price before I find flights for everyone.  I'm pretty sure Kayak's API could do this, but I don't have time to figure it out.

2. Movies starting near me in the next couple of hours with the added bonus of web ticket sales.  This seems like an iPhone app that should already exist.  I can't even find this on the web though.  Does movietickets.com or some other site let me search by zip code and time?

Anybody know where I can find these or want to build them for me for free?  Sweet.

screen: http://jmcpherson.org/screen.html
scp: http://kb.iu.edu/data/agye.html

1. ssh libbyh@sic.edu
2. screen
3. scp MyData libbyh@hosted.com:MyData
4. Ctrl+A, d
5. exit

That should do it. You can check in on the data transfer by typing this at the prompt:
screen -r
Hopefully your next big data migration will go as smoothly as mine did.