After a bit of toying around, here are my findings.

The Eclipse plugin is pretty slick. Deploying and build is simple.

The dev server that you spin up locally looks to be jetty under the hood.

Objects intended for storage are JDO annotated and after compiling, you run the .class files through the DataNucleus Enhancer which adds additional metadata so Google can map it to BigTable. The Eclipse plugin automatically performs this step for you after compiling. The examples provide a bunch of ant macros to help facilitate building/deploying.

One issue that I had was that the project was building with Java 1.6 and I would get an error after compiling:

Caused by: java.lang.UnsupportedClassVersionError: Bad version number in .class file

Even though they say they support Java 1.5 and 1.6, I guess this doesn’t work on the Java 1.6 for the Mac. Switching the build to 1.5 allows the DataNucleus Enhancer to run successfully.

Even though they are using JPA, some features have not yet been implemented or supported ( see http://code.google.com/appengine/docs/java/datastore/usingjpa.html#Unsupported_Features_of_JPA)

Overall, I like what I see so far and think this would be great for quick prototypes of web apps/services.

Going through the tutorial, my awesome Guestbook application has been created and deployed.

In my case, I had a form where there was a database column named “num_guests”, representing the number of guests. When the field fails to pass validation, the error messages is something like

Num guests is not a number

Not quite the text that we want. It would be better if it said

Number of guests is not a number

After doing a little bit of digging, I found the human_attribute_name method. You can override this method in your model class to provide alternative names for fields. To change our error message, I did the following

class Reservation < ActiveRecord::Base
  ...
  validates_presence_of :num_guests
  ...
  HUMAN_ATTRIBUTES = {
      :num_guests    => "Number of guests"
  }

  def self.human_attribute_name(attr)
      HUMAN_ATTRIBUTES[attr.to_sym] || super
  end
end

Since Rails 2.2, this method is used to support internationalization (i18n). Looking at it, it reminds me of Java’s Resource Bundles and Spring MVC’s error messages. Messages are defined based off a key and there’s a chain of look ups that get applied to resolve an error’s message.

Although, I don’t see myself doing any i18n work in the near-term, it is cool that we have that option now in Rails.

Do you think you would be able to recognize extraordinary talent when it is staring you in the face?

Video for viewing pleasure:

Specifically, checkboxes have always been a pain to deal with. The gotcha with checkboxes are if a checkbox isn’t checked, the request doesn’t send the parameter so it requires some additional checks to detect that the user deselected something that was there to update the field accordingly. I’ve been playing around with the Stripes framework and ran into this issue.

With Stripes, you can render a checkbox using their JSP tag:

<stripes:checkbox checked="true" name="property1" value="yes"/>
<stripes:checkbox checked="true" name="property2" value="no"/>

When the “checked” value is equal to “value” value, Stripes will render the checkbox as checked. So with the code shown, two checkboxes will be shown with the first checked and the second unchecked.

If a user reverses this by unchecking the first, checking the second, and submit the form, the HTTP request will only see that property2=no. Before the form was submitted, “property1″ had a value of “yes”. Now, “property1″ won’t even appear in the request parameters, so we have to do special handling to check for the absent of the parameter to update “property1″ to whatever value it should be when it is not checked.

In Spring MVC with form binding, checkboxes are dealt with a little differently. Using Spring MVC’s form JSP tag, you can do:

  <form:checkbox path="property1" value="yes"/>
  <form:checkbox path="property2" value="no"/>

Assuming your command bean is named “person”, this will generate the following HTML:

        <input name="person.property1" type="checkbox" value="yes"/>
        <input type="hidden" value="1" name="_person.property1"/>
        <input name="person.property2" type="checkbox" value="no"/>
        <input type="hidden" value="1" name="_person.property2"/>

As noted by the docs,

What you might not expect to see is the additional hidden field after each checkbox. When a checkbox in an HTML page is not checked, its value will not be sent to the server as part of the HTTP request parameters once the form is submitted, so we need a workaround for this quirk in HTML in order for Spring form data binding to work. The checkbox tag follows the existing Spring convention of including a hidden parameter prefixed by an underscore (”_”) for each checkbox. By doing this, you are effectively telling Spring that “the checkbox was visible in the form and I want my object to which the form data will be bound to reflect the state of the checkbox no matter what”.

Spring MVC also provides a “checkboxes” tag which allows you to render a list of checkbox boxes without having to wrap the “checkbox” tag around a JSTL forEach.

Hopefully, that gives you some insight into how to work with checkboxes in Stripes and Spring MVC.

All valid concerns. However, if IBM can maintain the developer community relationship that Sun and MySQL have built I think developers may have a lot to look forward to. Especially, government contractors.

First thing that popped into my mind when I read this was

Sweet! No more heavy-weight Oracle development. The government will allow devs to use MySQL now!

After all, it’s backed by Big Blue.

And nobody ever got fired for choosing IBM.

Right?

Installing Oracle on a laptop still gives me nightmares. *shudders*

I was presented with the following message:

Windows could not start because the following file is missing or corrupt:
system32hal.dll.
Please re-install a copy of the above file.

Uh, what?

Must be a fluke! So, let’s try this again.

Windows could not start because the following file is missing or corrupt:
system32ntoskrnl.dll.
Please re-install a copy of the above file.

Uh-oh. This doesn’t look good.

After googling a bit, it turns out Parallels does some pretty bad things like modify essential Windows boot up files to get Boot Camp to work with Parallels. They even modify boot.ini! So, I think what happened to me was that Parallels crashed at some point and corrupted/deleted these essential Windows files rendering my Windows partition unbootable.

This is what you call a deal breaker. If your software’s purpose is to allow other operating systems to run, rendering said operating system unusable is a big no no.

So, I’ve been using Fusion for a day or two now, feature for feature pretty much has everything Parallels had. Even the user interface is fairly similar, they just call things a little different. For example, what Parallels calls Coherence, Fusion calls Unity. Performance is about the same but I don’t really play games or anything other than startup Internet Explorer when running Windows. Best of all, Fusion doesn’t seem to do terrible things like modify Windows boot up files. Fusion beats Parallels hands down.

>> apachectl -V
Server version: Apache/2.2.9 (Unix)
Server built:   Sep 19 2008 10:58:54
Server's Module Magic Number: 20051115:15
Server loaded:  APR 1.2.7, APR-Util 1.2.7
Compiled using: APR 1.2.7, APR-Util 1.2.7
Architecture:   64-bit
Server MPM:     Prefork
  threaded:     no
    forked:     yes (variable process count)
Server compiled with....
 -D APACHE_MPM_DIR="server/mpm/prefork"
 -D APR_HAS_SENDFILE
 -D APR_HAS_MMAP
 -D APR_HAVE_IPV6 (IPv4-mapped addresses enabled)
 -D APR_USE_FLOCK_SERIALIZE
 -D APR_USE_PTHREAD_SERIALIZE
 -D SINGLE_LISTEN_UNSERIALIZED_ACCEPT
 -D APR_HAS_OTHER_CHILD
 -D AP_HAVE_RELIABLE_PIPED_LOGS
 -D DYNAMIC_MODULE_LIMIT=128
 -D HTTPD_ROOT="/usr"
 -D SUEXEC_BIN="/usr/bin/suexec"
 -D DEFAULT_PIDLOG="/private/var/run/httpd.pid"
 -D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
 -D DEFAULT_LOCKFILE="/private/var/run/accept.lock"
 -D DEFAULT_ERRORLOG="logs/error_log"
 -D AP_TYPES_CONFIG_FILE="/private/etc/apache2/mime.types"
 -D SERVER_CONFIG_FILE="/private/etc/apache2/httpd.conf"

To start up apache, you can do it a couple of ways.

Type sudo apachectl -k start

or

1. Go to System Preferences
2. Click on Sharing
3. Check the box that says Web Sharing

You can go to http://localhost or the URL provided in the Web Sharing screen to confirm apache is running and is able to serve up requests.

There is also a ~/Sites directory in your home folder. Apache is already setup to serve up files from this directory under http://localhost/~[username] where [username] is your user account name. Any files here will be render for example ~/Sites/index.html is accessible from the browser via http://localhost/~[username]/index.html.

One note to get this to work. Out of the box, all requests to /Sites result in a Forbidden 403 error. To resolve this issue, modify the conf file specified above as SERVER_CONFIG_FILE (/private/etc/apache2/httpd.conf in my case) from

<Directory />
    Options FollowSymLinks
    AllowOverride None
    Order deny,allow
    Deny from all
</Directory>

to

<Directory />
    Options FollowSymLinks
    AllowOverride None
    Order deny,allow
    Allow from all
</Directory>

Restart apache (sudo apachectl -k restart) and try going to http://localhost/~[username] again.

May your pockets be filled with little red envelopes.

I decided that I want all photos to be in one place and if I was going to use iPhoto, I’m going to import by copying the originals to the iPhoto Library. Before I could get all of this to happen, I had to backup all of existing photos that were not in the iPhoto Library to an external hard drive. Planning on importing these photos over again from the external hard drive, I then deleted all of these photos through Finder. Going back into iPhoto, I still saw the thumbnails for the photos I just deleted. If I attempt to open any of them though, it complained it couldn’t find the original. What a mess. There doesn’t seem to be a way to refresh your iPhoto Library and it would remove photos it doesn’t have references to any more.

I figure the easiest way to get my iPhoto Library setup the way I want it is to start from scratch. So I went under my Pictures directory and renamed iPhoto Library to iPhoto Library.original. Opening up iPhoto again, you get prompted to search for your Library or create a new one. I choose create a new iPhoto Library and now I can begin importing my photos.

After making sure I have the option to copy items to iPhoto Library when importing, I can now import photos from my external hard drive.

Great! Now I have all of my scattered photos in iPhoto Library. But what about the photos I had imported to the original iPhoto Library ( the ones under iPhoto Library.original)? Well, there didn’t seem to be an easy way to import non-broken originals form one iPhoto Library to another from the GUI so I went to the command line.

All of the original photos that are imported to an iPhoto Library are under a folder called Originals. However, due to the way iPhoto manages the photos, this also includes the broken files that reference the photos I had deleted. Basically I wanted to get rid of all of these broken references before importing all of the photos from my original iPhoto Library to the new one I am creating. Here’s how I did it.

1. Open up Terminal
2. Change directory to the original iPhoto Library’s Originals directory (~/Pictures/iPhoto Library.original/Originals)
3. The broken references aren’t actually symbolic links. They seem to be using extended file attributes to denote where the original file actually is (see xattr).  Since we deleted the actual photos, to identify these files type:

   find . -size 0
   

   to get a list of all of the 0 byte files.

4. To remove them:

   find . -name "*.jpg" -size 0 -exec rm {}  \;
   

   or if you want to just move them elsewhere:

   find . -name "*.jpg" -size 0 -exec mv {} $dest \;
   

   where $dest is the path to where you want to move the files

5. To delete all of the empty directories (that represent your events) for clean up purposes:

   find . -depth -type d -empty -exec rmdir {} \;

Now your original iPhoto Library should only contain photos that were imported by copying the originals to the iPhoto Library.

To finish importing everything, open iPhoto, choosing your new iPhoto Library and import the Originals directory from the original iPhoto Library (~/Pictures/iPhoto Library.originals/Originals). You might have to copy this folder someplace else since the Import menu doesn’t allow you to specify going into the iPhoto Library.originals package.

After about 5 hours of battling with iPhoto, I think I finally have all of my photos reimported to a fresh iPhoto Library with no duplicates and broken file references. Having to do all of this really makes me think to just switch to something else. How do you guys feel about iPhoto? What are some good alternatives? Picasa anyone?

This allowed requests to blog.notedpath.com/* and theodorenguyen-cao/* respond with the same content. I thought I was done. I discovered this wasn’t the case when I saw blog.notedpath.com as a direct traffic source in my google analytics for theodorenguyen-cao.com. To fix the screwed up analytics, I needed to make it so that all requests that go to blog.notedpath.com are permanently redirected (301) to theodorenguyen-cao.com.

To do this I had to apply an Apache mod_alias redirect directive as such:

<VirtualHost *:80>
        VirtualDocumentRoot /var/www/blog
        ServerName blog.notedpath.com
        Redirect permanent / http://www.theodorenguyen-cao.com/
        ErrorLog /var/log/apache2/wp-error.log
        TransferLog /var/log/apache2/wp-access.log
</VirtualHost>

The virtual host for theodorenguyen-cao.com looks like:

<VirtualHost *:80>
    VirtualDocumentRoot /var/www/blog
    ServerName www.theodorenguyen-cao.com
    ServerAlias theodorenguyen-cao.com
    CustomLog /var/log/apache2/theodorenguyen-cao.com_access.log Combined
    ErrorLog /var/log/apache2/theodorenguyen-cao_error.log
</VirtualHost>

At first I thought this would only fix the simple case of blog.notedpath.com redirecting to theodorenguyen-cao.com, but blog.notepath.com/foobar not being translated to theodorenguyen-cao.com/foobar. However, this does exactly what I want. All blog.notedpath.com URLs will be replaced with theodorenguyen-cao.com URLs. Old bookmarks will simply redirect to a theodorenguyen-cao.com URL and not 404.

Success!

I’m still waiting to see if Google will update the search result links that point to blog.notedpath.com to be theodorenguyen-cao.com URLs.

Digging into it, it turns out the way  for validates_presence_of relies on Object#blank which of course when sent

false.blank? # returns true

Reading up on the documentation, it is suggested to use validates_inclusion_of when dealing with booleans.

The one line change solved the problem:

validates_inclusion_of :accepted, :in => [true, false]

For the web galleries, I really liked Picasa’s layout over Flickr’s. The web site is a lot more simplistic and easy to navigate. Maybe it’s becase I’m so familiar with other Google services. Flickr’s slideshow is so awesome though. Viewing your photostream through Cooliris is such beautiful eye candy.

I started with the free accounts. Google gives you a gig of space for the free account and you can create as many albums as you want. Flickr’s free account gives you 100 mb of upload per month and limits you to three sets.

For me, it really came down to pricing. In order to get more disk space for Picasa, you have to purchase more storage. Starting purchase goes for $20/yr for 10gigs up to $500/yr for 400GB. This storage is actually not specific to Picasa but is shared by all other Google services that need to use extra space. Flickr offers a Pro account, which gives you unlimited storage space for your videos and photos and allows you to create any number of sets and collections, for $24.95.

Given the number of photos I want to upload and my budget, I went with Flickr. Today, storage is so cheap. For $25 bucks, I should be able to get unlimited storage for a service like photo sharing. I’ve started to upload some photos I’ve had for awhile and never really shared them with those who would most enjoy them. It’s been really fun going through old pictures. My photostream can be found here.

Don’t use a big word where a diminutive one will suffice.

So after finding out the domain was available, diminutiveurl.com was born. Yes, it’s poking a little fun at the idea of a tiny url but it was fun to hack on.  It’s very minimilistic at this point but I hope to add some interesting features.

For no other reason than to build something, I hope you enjoy it! I am glad to present diminitiveurl.com! Please let me know what you think.

.

I’m sure there are some kinks to iron out but please check out theoandpat.com and let us know what you think.  Oh, yeah also, RSVP for the wedding. If you’re reading my blog, chances are I know you and you’re invited.

-Theo

First thing I did was switch out the default mysql config with one tweaked for smaller boxes. This configuration actually came with the mysql installation under /usr/share/doc/mysql-server-5.0/examples/. Just backup your existing my.cnf (mine is located under /etc/mysql) and use the following:

# The following options will be passed to all MySQL clients
[client]
port		= 3306
socket		= /var/run/mysqld/mysqld.sock

# Here follows entries for some specific programs

# The MySQL server
[mysqld]
port		= 3306
socket		= /var/run/mysqld/mysqld.sock
skip-locking
key_buffer = 16K
max_allowed_packet = 1M
table_cache = 4
sort_buffer_size = 64K
read_buffer_size = 256K
read_rnd_buffer_size = 256K
net_buffer_length = 2K
thread_stack = 64K

# Don't listen on a TCP/IP port at all. This can be a security enhancement,
# if all processes that need to connect to mysqld run on the same host.
# All interaction with mysqld must be made via Unix sockets or named pipes.
# Note that using this option without enabling named pipes on Windows
# (using the "enable-named-pipe" option) will render mysqld useless!
#
#skip-networking
server-id	= 1

# Uncomment the following if you want to log updates
#log-bin=mysql-bin

# Uncomment the following if you are NOT using BDB tables
#skip-bdb

# Uncomment the following if you are using InnoDB tables
#innodb_data_home_dir = /var/lib/mysql/
#innodb_data_file_path = ibdata1:10M:autoextend
#innodb_log_group_home_dir = /var/lib/mysql/
#innodb_log_arch_dir = /var/lib/mysql/
# You can set .._buffer_pool_size up to 50 - 80 %
# of RAM but beware of setting memory usage too high
#innodb_buffer_pool_size = 16M
#innodb_additional_mem_pool_size = 2M
# Set .._log_file_size to 25 % of buffer pool size
#innodb_log_file_size = 5M
#innodb_log_buffer_size = 8M
#innodb_flush_log_at_trx_commit = 1
#innodb_lock_wait_timeout = 50

[mysqldump]
quick
max_allowed_packet = 16M

[mysql]
no-auto-rehash
# Remove the next comment character if you are not familiar with SQL
#safe-updates

[isamchk]
key_buffer = 8M
sort_buffer_size = 8M

[myisamchk]
key_buffer = 8M
sort_buffer_size = 8M

[mysqlhotcopy]
interactive-timeout

You can see estimated memory usage with a config if you just copy paste the configuration file here.

Restart MySQL (/etc/init.d/mysql restart).

The second thing I did was check out MySQLTuner. Just download the perl script and run it. It will run some analysis on your mysql setup and provide some performance and configuration tweak recommendations.

Sample output looks like this:

 >>  MySQLTuner 1.0.0 - Major Hayden 
 >>  Bug reports, feature requests, and downloads at http://mysqltuner.com/
 >>  Run with '--help' for additional options and output filtering
Please enter your MySQL administrative login: root
Please enter your MySQL administrative password: 

-------- General Statistics --------------------------------------------------
[--] Skipped version check for MySQLTuner script
[OK] Currently running supported MySQL version 5.0.51a-3ubuntu5.4
[OK] Operating on 64-bit architecture

-------- Storage Engine Statistics -------------------------------------------
[--] Status: +Archive -BDB -Federated +InnoDB -ISAM -NDBCluster
[--] Data in MyISAM tables: 867K (Tables: 18)
[--] Data in InnoDB tables: 704K (Tables: 40)
[!!] Total fragmented tables: 2

-------- Performance Metrics -------------------------------------------------
[--] Up for: 14h 57m 0s (17K q [0.316 qps], 699 conn, TX: 55M, RX: 3M)
[--] Reads / Writes: 96% / 4%
[--] Total buffers: 26.0M global + 824.0K per thread (100 max threads)
[OK] Maximum possible memory usage: 106.5M (41% of installed RAM)
[OK] Slow queries: 0% (0/17K)
[OK] Highest usage of available connections: 6% (6/100)
[!!] Key buffer size / total MyISAM indexes: 16.0K/381.0K
[!!] Key buffer hit rate: 88.5% (154K cached / 17K reads)
[!!] Query cache is disabled
[OK] Sorts requiring temporary tables: 0% (0 temp sorts / 4K sorts)
[!!] Temporary tables created on disk: 30% (1K on disk / 4K total)
[!!] Thread cache is disabled
[!!] Table cache hit rate: 0% (4 open / 7K opened)
[OK] Open file limit used: 0% (8/1K)
[OK] Table locks acquired immediately: 99% (17K immediate / 17K locks)
[OK] InnoDB data size / buffer pool: 704.0K/8.0M

-------- Recommendations -----------------------------------------------------
General recommendations:
    Run OPTIMIZE TABLE to defragment tables for better performance
    MySQL started within last 24 hours - recommendations may be inaccurate
    Enable the slow query log to troubleshoot bad queries
    When making adjustments, make tmp_table_size/max_heap_table_size equal
    Reduce your SELECT DISTINCT queries without LIMIT clauses
    Set thread_cache_size to 4 as a starting value
    Increase table_cache gradually to avoid file descriptor limits
Variables to adjust:
    key_buffer_size (> 381.0K)
    query_cache_size (>= 8M)
    tmp_table_size (> 32M)
    max_heap_table_size (> 16M)
    thread_cache_size (start at 4)
    table_cache (> 4)

I haven’t made any of the recommended changes yet though. I am going to try to see how this default small config performs.

I’ll try to follow up with any of my findings.

For low traffic sites (like mine), this idle timeout may be reached causing the next visitor to our website to experience a really long delay before page load. What we really want is an option to set a minimum number of instances. This would allow us to automatically spin up an instance during start up and keep it around. Unfortunately at this time, it doesn’t look like there is a way to set this.

As a workaround, I’ve setup a crontab that makes a request to my application every 5 minutes to prevent mod_rails from killing off all application instances.

To do this just run:

crontab -e

And then specific the following cron

*/5 * * * * wget -O /dev/null http://www.myapp.com 2>/dev/null

You can verify this is working correctly but just tailing your application logs and verify every 5 minutes you get a request.

You can also run

 passenger-status

You should see at least the count variable to be at least 1 instance.

Note, this workaround will not immediate start up an instance upon restart. You can add an initial request as part of your post deploy capistrano task though. You probably should be making sure your application is up after deploying or restarting the application anyways.

The process was dead simple.

1. Install the passenger gem

   sudo gem install passenger

2. Install passenger as an Apache module

   passenger-install-apache2-module

3. Load the passenger apache module by editing the Apache config

   LoadModule passenger_module /usr/lib/ruby/gems/1.8/gems/passenger-2.0.5/ext/apache2/mod_passenger.so
   PassengerRoot /usr/lib/ruby/gems/1.8/gems/passenger-2.0.5
   PassengerRuby /usr/bin/ruby1.8
   

4. Restart Apache

If all things went well, you have everything installed you need. If there were some missing dependencies, you should be presented with how to install those dependencies.

In the installation output, it tells you how to mod_railsify your apps by creating a vhost as such:

<VirtualHost *:80>
    ServerName www.mywebsite.com
    DocumentRoot /home/deploy/mywebsite/public
</VirtualHost>

That’s it! No more of this proxy balancer and mongrel_cluster.yml configuration.

There’s some magic going on in the background. As requests come in, passenger will spin up more application instances. For more tweaking your configuration options check out the user guide.

Go to your website and you should see your rails app up and running.

So now we have your app up and running, how do we update or restart our app? Passenger provides two ways for us to do this.

The first is whenever apache is restarted, your application is restarted.

The second way allows us to restart a specified application without affecting Apache. Whenever passenger detects tmp/restart.txt, it will restart the application instances for us. We can integrate this into our Capistrano deploy flow by adding the following our config/deploy.rb

namespace :passenger do
  desc "Restart Application"
  task :restart do
    run "touch #{current_path}/tmp/restart.txt"
  end
end

after :deploy, "passenger:restart"

This will create that restart.txt after the cap:deploy task gets executed, causing the application to restart.

Finally, passenger comes with some pretty useful utilities.

Check out passenger-status which produces output showing current passenger server statuses.

Sample output:

----------- General information -----------
max      = 6
count    = 1
active   = 0
inactive = 1
Using global queue: no
Waiting on global queue: 0

----------- Applications -----------
/home/deploy/www.myapp.com/releases/20081206183156:
  PID: 30784     Sessions: 0

Another utility passenger-memory-status gives you insight into how much memory is being used by apache and passenger.

Sample output:

-------------- Apache processes ---------------
PID    PPID   Threads  VMSize    Private  Name
-----------------------------------------------
12841  1      1        225.9 MB  0.0 MB   /usr/sbin/apache2 -k start
28294  12841  1        248.4 MB  21.4 MB  /usr/sbin/apache2 -k start
28300  12841  1        243.7 MB  0.5 MB   /usr/sbin/apache2 -k start
28306  12841  1        248.4 MB  4.4 MB   /usr/sbin/apache2 -k start
28357  12841  1        249.1 MB  19.8 MB  /usr/sbin/apache2 -k start
29400  12841  1        249.4 MB  3.7 MB   /usr/sbin/apache2 -k start
29788  12841  1        249.3 MB  21.7 MB  /usr/sbin/apache2 -k start
29834  12841  1        245.8 MB  18.9 MB  /usr/sbin/apache2 -k start
29836  12841  1        245.8 MB  9.3 MB   /usr/sbin/apache2 -k start
29868  12841  1        245.8 MB  2.4 MB   /usr/sbin/apache2 -k start
29870  12841  1        246.5 MB  5.2 MB   /usr/sbin/apache2 -k start
### Processes: 11
### Total private dirty RSS: 107.44 MB

--------- Passenger processes ----------
PID    Threads  VMSize    Private  Name
----------------------------------------
28031  10       15.3 MB   0.1 MB   /usr/lib/ruby/gems/1.8/gems/passenger-2.0.5/ext/apache2/ApplicationPoolServerExecutable 0 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.5/bin/passenger-spawn-server  /usr/bin/ruby1.8  /tmp/passenger_status.12841.fifo
28032  2        48.7 MB   0.6 MB   Passenger spawn server
29161  1        114.8 MB  0.7 MB   Passenger FrameworkSpawner: 2.1.2
30461  1        122.8 MB  32.3 MB  Passenger ApplicationSpawner: /home/deploy/www.myapp.com/releases/20081206183156
30784  1        129.3 MB  33.4 MB  Rails: /home/deploy/www.myapp.com/releases/20081206183156
### Processes: 5
### Total private dirty RSS: 67.08 MB

Pretty sweet.

This is a pretty well documented bug. Luckily, there are a couple of ways to fix this.

Here are my two favorites:

The first solution is well documented:

Download iepngfix.zip. The development version 2.0 Alpha 3 has support for background position and repeat. Extract the zip and copy iepngfix.htc and blank.gif somewhere. I put in under stylesheets.

Add the following snippet to your CSS stylesheet:

img {
	behavior: url(/stylesheets/iepngfix.htc);
}

And you’re done! Hit refresh in IE6 and transparent PNG images should render correctly now.

You can add apply this fix to other elements that may be using PNG images as CSS background images as such:

img, #logo {
	behavior: url(/stylesheets/iepngfix.htc);
}

where logo is a div that has a background-image that is a transparent PNG.

Note: If you are using v2.0 and want to take advantage of background-repeat and position support, copy iepngfix_tilebg.js to your javascripts folder and include the js file in the HTML files you need it for.

The second way to fix this is to get everyone off IE6 but I guess that’s just wishful thinking…

theo@theo~/dev $ sudo gem update
Updating installed gems
...
Updating rubygems-update
Successfully installed rubygems-update-1.3.1
ERROR:  While executing gem ... (NameError)
    undefined local variable or method `remote_gemspecs' for #

Reading the release notes:

NOTE: RubyGems 1.1 and 1.2 have problems upgrading when there is no
rubygems-update installed. You will need to follow the second set of update
instructions if you see “Nothing to update”.

shows that we need to install and run the rubygem-update gem to get this fixed

  theo@theo~/dev $ sudo gem install rubygems-update
Successfully installed rubygems-update-1.3.1
1 gem installed
  theo@theo~/dev $ sudo update_rubygems
Installing RubyGems 1.3.1
mkdir -p /Library/Ruby/Site/1.8
mkdir -p /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin
install -c -m 0644 rbconfig/datadir.rb /Library/Ruby/Site/1.8/rbconfig/datadir.rb
install -c -m 0644 rubygems/builder.rb /Library/Ruby/Site/1.8/rubygems/builder.rb
install -c -m 0644 rubygems/command.rb /Library/Ruby/Site/1.8/rubygems/command.rb
install -c -m 0644 rubygems/command_manager.rb /Library/Ruby/Site/1.8/rubygems/command_manager.rb
install -c -m 0644 rubygems/commands/build_command.rb /Library/Ruby/Site/1.8/rubygems/commands/build_command.rb
install -c -m 0644 rubygems/commands/cert_command.rb /Library/Ruby/Site/1.8/rubygems/commands/cert_command.rb
install -c -m 0644 rubygems/commands/check_command.rb /Library/Ruby/Site/1.8/rubygems/commands/check_command.rb
install -c -m 0644 rubygems/commands/cleanup_command.rb /Library/Ruby/Site/1.8/rubygems/commands/cleanup_command.rb
install -c -m 0644 rubygems/commands/contents_command.rb /Library/Ruby/Site/1.8/rubygems/commands/contents_command.rb
install -c -m 0644 rubygems/commands/dependency_command.rb /Library/Ruby/Site/1.8/rubygems/commands/dependency_command.rb
install -c -m 0644 rubygems/commands/environment_command.rb /Library/Ruby/Site/1.8/rubygems/commands/environment_command.rb
install -c -m 0644 rubygems/commands/fetch_command.rb /Library/Ruby/Site/1.8/rubygems/commands/fetch_command.rb
install -c -m 0644 rubygems/commands/generate_index_command.rb /Library/Ruby/Site/1.8/rubygems/commands/generate_index_command.rb
install -c -m 0644 rubygems/commands/help_command.rb /Library/Ruby/Site/1.8/rubygems/commands/help_command.rb
install -c -m 0644 rubygems/commands/install_command.rb /Library/Ruby/Site/1.8/rubygems/commands/install_command.rb
install -c -m 0644 rubygems/commands/list_command.rb /Library/Ruby/Site/1.8/rubygems/commands/list_command.rb
install -c -m 0644 rubygems/commands/lock_command.rb /Library/Ruby/Site/1.8/rubygems/commands/lock_command.rb
install -c -m 0644 rubygems/commands/mirror_command.rb /Library/Ruby/Site/1.8/rubygems/commands/mirror_command.rb
install -c -m 0644 rubygems/commands/outdated_command.rb /Library/Ruby/Site/1.8/rubygems/commands/outdated_command.rb
install -c -m 0644 rubygems/commands/pristine_command.rb /Library/Ruby/Site/1.8/rubygems/commands/pristine_command.rb
install -c -m 0644 rubygems/commands/query_command.rb /Library/Ruby/Site/1.8/rubygems/commands/query_command.rb
install -c -m 0644 rubygems/commands/rdoc_command.rb /Library/Ruby/Site/1.8/rubygems/commands/rdoc_command.rb
install -c -m 0644 rubygems/commands/search_command.rb /Library/Ruby/Site/1.8/rubygems/commands/search_command.rb
install -c -m 0644 rubygems/commands/server_command.rb /Library/Ruby/Site/1.8/rubygems/commands/server_command.rb
install -c -m 0644 rubygems/commands/sources_command.rb /Library/Ruby/Site/1.8/rubygems/commands/sources_command.rb
install -c -m 0644 rubygems/commands/specification_command.rb /Library/Ruby/Site/1.8/rubygems/commands/specification_command.rb
install -c -m 0644 rubygems/commands/stale_command.rb /Library/Ruby/Site/1.8/rubygems/commands/stale_command.rb
install -c -m 0644 rubygems/commands/uninstall_command.rb /Library/Ruby/Site/1.8/rubygems/commands/uninstall_command.rb
install -c -m 0644 rubygems/commands/unpack_command.rb /Library/Ruby/Site/1.8/rubygems/commands/unpack_command.rb
install -c -m 0644 rubygems/commands/update_command.rb /Library/Ruby/Site/1.8/rubygems/commands/update_command.rb
install -c -m 0644 rubygems/commands/which_command.rb /Library/Ruby/Site/1.8/rubygems/commands/which_command.rb
install -c -m 0644 rubygems/config_file.rb /Library/Ruby/Site/1.8/rubygems/config_file.rb
install -c -m 0644 rubygems/custom_require.rb /Library/Ruby/Site/1.8/rubygems/custom_require.rb
install -c -m 0644 rubygems/defaults.rb /Library/Ruby/Site/1.8/rubygems/defaults.rb
install -c -m 0644 rubygems/dependency.rb /Library/Ruby/Site/1.8/rubygems/dependency.rb
install -c -m 0644 rubygems/dependency_installer.rb /Library/Ruby/Site/1.8/rubygems/dependency_installer.rb
install -c -m 0644 rubygems/dependency_list.rb /Library/Ruby/Site/1.8/rubygems/dependency_list.rb
install -c -m 0644 rubygems/digest/digest_adapter.rb /Library/Ruby/Site/1.8/rubygems/digest/digest_adapter.rb
install -c -m 0644 rubygems/digest/md5.rb /Library/Ruby/Site/1.8/rubygems/digest/md5.rb
install -c -m 0644 rubygems/digest/sha1.rb /Library/Ruby/Site/1.8/rubygems/digest/sha1.rb
install -c -m 0644 rubygems/digest/sha2.rb /Library/Ruby/Site/1.8/rubygems/digest/sha2.rb
install -c -m 0644 rubygems/doc_manager.rb /Library/Ruby/Site/1.8/rubygems/doc_manager.rb
install -c -m 0644 rubygems/exceptions.rb /Library/Ruby/Site/1.8/rubygems/exceptions.rb
install -c -m 0644 rubygems/ext/builder.rb /Library/Ruby/Site/1.8/rubygems/ext/builder.rb
install -c -m 0644 rubygems/ext/configure_builder.rb /Library/Ruby/Site/1.8/rubygems/ext/configure_builder.rb
install -c -m 0644 rubygems/ext/ext_conf_builder.rb /Library/Ruby/Site/1.8/rubygems/ext/ext_conf_builder.rb
install -c -m 0644 rubygems/ext/rake_builder.rb /Library/Ruby/Site/1.8/rubygems/ext/rake_builder.rb
install -c -m 0644 rubygems/ext.rb /Library/Ruby/Site/1.8/rubygems/ext.rb
install -c -m 0644 rubygems/format.rb /Library/Ruby/Site/1.8/rubygems/format.rb
install -c -m 0644 rubygems/gem_openssl.rb /Library/Ruby/Site/1.8/rubygems/gem_openssl.rb
install -c -m 0644 rubygems/gem_path_searcher.rb /Library/Ruby/Site/1.8/rubygems/gem_path_searcher.rb
install -c -m 0644 rubygems/gem_runner.rb /Library/Ruby/Site/1.8/rubygems/gem_runner.rb
install -c -m 0644 rubygems/indexer.rb /Library/Ruby/Site/1.8/rubygems/indexer.rb
install -c -m 0644 rubygems/install_update_options.rb /Library/Ruby/Site/1.8/rubygems/install_update_options.rb
install -c -m 0644 rubygems/installer.rb /Library/Ruby/Site/1.8/rubygems/installer.rb
install -c -m 0644 rubygems/local_remote_options.rb /Library/Ruby/Site/1.8/rubygems/local_remote_options.rb
install -c -m 0644 rubygems/old_format.rb /Library/Ruby/Site/1.8/rubygems/old_format.rb
install -c -m 0644 rubygems/package/f_sync_dir.rb /Library/Ruby/Site/1.8/rubygems/package/f_sync_dir.rb
install -c -m 0644 rubygems/package/tar_header.rb /Library/Ruby/Site/1.8/rubygems/package/tar_header.rb
install -c -m 0644 rubygems/package/tar_input.rb /Library/Ruby/Site/1.8/rubygems/package/tar_input.rb
install -c -m 0644 rubygems/package/tar_output.rb /Library/Ruby/Site/1.8/rubygems/package/tar_output.rb
install -c -m 0644 rubygems/package/tar_reader/entry.rb /Library/Ruby/Site/1.8/rubygems/package/tar_reader/entry.rb
install -c -m 0644 rubygems/package/tar_reader.rb /Library/Ruby/Site/1.8/rubygems/package/tar_reader.rb
install -c -m 0644 rubygems/package/tar_writer.rb /Library/Ruby/Site/1.8/rubygems/package/tar_writer.rb
install -c -m 0644 rubygems/package.rb /Library/Ruby/Site/1.8/rubygems/package.rb
install -c -m 0644 rubygems/platform.rb /Library/Ruby/Site/1.8/rubygems/platform.rb
install -c -m 0644 rubygems/remote_fetcher.rb /Library/Ruby/Site/1.8/rubygems/remote_fetcher.rb
install -c -m 0644 rubygems/require_paths_builder.rb /Library/Ruby/Site/1.8/rubygems/require_paths_builder.rb
install -c -m 0644 rubygems/requirement.rb /Library/Ruby/Site/1.8/rubygems/requirement.rb
install -c -m 0644 rubygems/rubygems_version.rb /Library/Ruby/Site/1.8/rubygems/rubygems_version.rb
install -c -m 0644 rubygems/security.rb /Library/Ruby/Site/1.8/rubygems/security.rb
install -c -m 0644 rubygems/server.rb /Library/Ruby/Site/1.8/rubygems/server.rb
install -c -m 0644 rubygems/source_index.rb /Library/Ruby/Site/1.8/rubygems/source_index.rb
install -c -m 0644 rubygems/source_info_cache.rb /Library/Ruby/Site/1.8/rubygems/source_info_cache.rb
install -c -m 0644 rubygems/source_info_cache_entry.rb /Library/Ruby/Site/1.8/rubygems/source_info_cache_entry.rb
install -c -m 0644 rubygems/spec_fetcher.rb /Library/Ruby/Site/1.8/rubygems/spec_fetcher.rb
install -c -m 0644 rubygems/specification.rb /Library/Ruby/Site/1.8/rubygems/specification.rb
install -c -m 0644 rubygems/test_utilities.rb /Library/Ruby/Site/1.8/rubygems/test_utilities.rb
install -c -m 0644 rubygems/timer.rb /Library/Ruby/Site/1.8/rubygems/timer.rb
install -c -m 0644 rubygems/uninstaller.rb /Library/Ruby/Site/1.8/rubygems/uninstaller.rb
install -c -m 0644 rubygems/user_interaction.rb /Library/Ruby/Site/1.8/rubygems/user_interaction.rb
install -c -m 0644 rubygems/validator.rb /Library/Ruby/Site/1.8/rubygems/validator.rb
install -c -m 0644 rubygems/version.rb /Library/Ruby/Site/1.8/rubygems/version.rb
install -c -m 0644 rubygems/version_option.rb /Library/Ruby/Site/1.8/rubygems/version_option.rb
install -c -m 0644 rubygems.rb /Library/Ruby/Site/1.8/rubygems.rb
install -c -m 0644 ubygems.rb /Library/Ruby/Site/1.8/ubygems.rb
cp gem /tmp/gem
install -c -m 0755 /tmp/gem /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/gem
rm /tmp/gem
rm -f /Users/theo/.gem/source_cache
rm -f /Library/Ruby/Gems/1.8/source_cache
Removing old RubyGems RDoc and ri
rm -rf /Library/Ruby/Gems/1.8/doc/rubygems-1.2.0
Installing rubygems-1.3.1 ri into /Library/Ruby/Gems/1.8/doc/rubygems-1.3.1/ri
Installing rubygems-1.3.1 rdoc into /Library/Ruby/Gems/1.8/doc/rubygems-1.3.1/rdoc

------------------------------------------------------------------------------

= Announce: RubyGems Release 1.3.0

NOTE:  RubyGems 1.1 and 1.2 have problems upgrading when there is no
rubygems-update installed.  You will need to follow the second set of update
instructions if you see "Nothing to update".

Release 1.3.0 fixes some bugs.

Bugs fixed:

* Disregard ownership of ~ under Windows while creating ~/.gem.  Fixes
  issues related to no uid support under Windows.
* Fix requires for Gem::inflate, Gem::deflate, etc.
* Make Gem.dir respect :gemhome value from config.  (Note: this feature may be
  removed since it is hard to implement on 1.9.)
* Kernel methods are now private.  Patch #20801 by Stefan Rusterholz.
* Gem::location_of_caller now behaves on Windows.  Patch by Daniel Berger.
* Silence PATH warning.

Deprecation Notices:

* Gem::manage_gems will be removed on or after March 2009.

For a full list of changes to RubyGems and the contributor for each change, see
the ChangeLog file.

Special thanks to Chad Wooley for backwards compatibility testing and Luis
Lavena for continuing windows support.

== How can I get RubyGems?

NOTE:  If you have installed RubyGems using a package system you may want to
install a new RubyGems through the same packaging system.

If you have a recent version of RubyGems (0.8.5 or later), then all
you need to do is:

  $ gem update --system   (you might need to be admin/root)

NOTE:  RubyGems 1.1 and 1.2 have problems upgrading when there is no
rubygems-update installed.  You will need to follow the second set of update
instructions if you see "Nothing to update".

NOTE: You may have to run the command twice if you have any previosly
installed rubygems-update gems.

If you have an older version of RubyGems installed, then you can still
do it in two steps:

  $ gem install rubygems-update  (again, might need to be admin/root)
  $ update_rubygems              (... here too)

If you don't have any gems install, there is still the pre-gem
approach to getting software ... doing it manually:

1. DOWNLOAD FROM: http://rubyforge.org/frs/?group_id=126
2. UNPACK INTO A DIRECTORY AND CD THERE
3. INSTALL WITH:  ruby setup.rb  (you may need admin/root privilege)

== To File Bugs

The RubyGems bug tracker can be found on RubyForge at:
http://rubyforge.org/tracker/?func=add&group_id=126&atid=575

When filing a bug, `gem env` output will be helpful in diagnosing the issue.

If you find a bug where RubyGems crashes, please provide debug output. You can
do that with `gem --debug the_command`.

== Thanks

Keep those gems coming!

-- Jim & Chad & Eric (for the RubyGems team)

------------------------------------------------------------------------------

RubyGems installed the following executables:
	/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/gem

If `gem` was installed by a previous RubyGems installation, you may need
to remove it by hand.

As time goes on, I’ve been able to do a little bit of both and I’ve developed a strong preference for pair programming over code reviews.

With code reviews, you get one or more other persons to review the code you just wrote and feel ready is to be checked in, deployed, or whatever the next step is.  These reviews can be very formal or just as simple as a line-by-line walk through the code.  The goal is to find any bugs or fixes before the code gets to the next step.  This is very analogous to the writer/editor/publisher workflow (kind of like this blog entry).  Writer writes the article, editor proofreads, and the article gets published.  Programmer writes the code, other developers review the code, and the code gets deployed.  It almost seems like the idea of code reviews came out of software methodologies like the Waterfall model.  Everything is very sequential and done in distinct stages.

In pair programming, the focus is on developing “good” code the first time around.  We do this by having more than one pair of eyes on the working code as it is being written.  One person is the “driver” who is writing the code and the other is the guide or observer who is verifying the code being written and thinking of potential improvements. The developers switch roles whenever it makes sense which in many cases causes one developer to immediate use or have to work with the code that was written by their partner. It places emphasis on the idea that two heads are better than one.

Two things come to my mind when I think about pair programming and code reviews. First, code reviews seem to be a just-in-the-nick-of-time fix for finding bugs in code before it goes out the door.  The initial development effort as already been completed and now we are evaluating the work.  And realistic, this is code we’re looking at. Everyone has their opinion as how things should be structured, design philosophies, coding styles, etc.  Many times code review sessions end up focusing on higher level concepts like those previously listed and not on the code itself. These kind of debates are related to decisions that should have been made prior to writing this code.  Why are we asking ourselves why we did this this way now after we’ve already spent time and effort to write code for it? And the people part of the code review are not neccessarily the people that will be working with that piece of code.

That brings me to my second thought which is this is all reminiscent of Scrum pigs and chickens.

In code reviews, people sit down to review someone’s code.  Everyone has an opinion but not everyone is going to be working with the code on a daily basis. At the time, everyone seems to be involved in the process but there is no vested interest. They are just looking at some code and asking themselves “does this code look good and is it correct?”.  It’s a very passive standpoint. On the other hand, pair programmers are completely invested (committed?) in the task at hand.  They immediately are using the code they are writing together and collobarating their thoughts on design, code layout, etc. Both programmers are taking on an active role and are emotionally invested in the task at hand because they are attacking the same problem together.

Most of the cons of pair programming can be attributed to developer social/ego issues. And they are not specific to pair programming. Going down the list of drawbacks listed on Wikipedia:

• Developer egos: Experienced developers may find it tedious to tutor a less experienced developer in a paired environment.
• Developer intimidation: A less experienced developer may feel intimidated pairing with a more experienced developer which may result in less participation.
• Developer work preference: Some engineers prefer to work alone, and may find the paired environment cumbersome.
• Tutoring cost: Experienced developers working alone may be capable of producing code that is clean and accurate at the outset, and the additional theoretical gain from pairing might not be worth the cost of an additional developer. This is especially true when producing more trivial parts of the system.
• Potential conflict: Differences in coding style may result in conflict, and personality conflicts can result in one or both developers feeling awkward or uncomfortable.
• Chat sessions: Sometimes employees might talk together too much, straying excessively into off-topic subjects, such as major news events, personal problems, etc.
• Annoying personal habits: Sometimes people can find each other much more annoying when working up close than at separate workstations.

Developer egos, intimidation, work preference, and tutoring costs are things that should be checked at the door. As an experience developer, you should look for opportunities to help your fellow developers to learn and improve their skills. As a more junior developer, the opportunity to take chances and try to prove yourself is one of the best ways to learn and develop better skills. I don’t know about other people but collaborative work environments seem to be a plus. Being able to discuss your ideas openly is one of the best ways to make what you’re building better than it is. As for potential conflicts, chat sessions, and annoying personal habits, these have more to do with personalities and mannerism in the work place. All of this can happen in code reviews as well but the point is being self-aware and respectful of your coworkers is just as important as writing awesome code.

While I’m not against code reviews, I feel that pair programming is better suited to improve both code and team quality.