Overall, the conference was really good. Berlin is an amazing city and the majority of the talks were really good. Of special note were the ones by Dr. Nic, Topfunky, and Evan Phoenix. Their talks about ruby magic, css generation, and rubinius were really well done.

To make things easier for you, I’ve also embeded the videos after the jump. Francis’s video is first with mine second. Sorry for the occasional fuzzy video quality, I’m still not good at filming presentations.

Unfortunately, the version of ctags that ships with Mac OS X is a piece of crap. Looking at the man page it’s only version 3.0 from 1993. That’s 13 years ago for those of you not into math. Anyway, the fix is simple (that’s in bold for those of you from google). Just install Darwin Port and then enter

sudo port install ctags

That’ll get you up and good with a modern version.

P.S. – If you really want to install this by source and do not know how, let me know. I can easily do another write up on how that’s done.

Pound is dead simple to setup and configure. Unfortunately, the darwin port for pound is old and does not work. So this guide will help you build pound on your own. Besides, everyone feels cooler after compiling that hot fire. Click on for the steps.

1. Open terminal.
2. Install zlib

mkdir ~/temp
curl -O http://www.zlib.net/zlib-1.2.3.tar.gz
tar xzvf zlib-1.2.3.tar.gz
cd zlib-1.2.3
./configure --prefix=/usr/local --shared
make
sudo make install

3. Install openssl

curl -O http://www.openssl.org/source/openssl-0.9.8b.tar.gz
tar xzvf openssl-0.9.8b.tar.gz
cd openssl-0.9.8b
./config -L/usr/local/lib --openssldir=/usr/local/etc/openssl \\
    zlib no-asm no-krb5 shared
make
sudo make install

4. Install Pound 2.0 or greater

curl -O http://www.apsis.ch/pound/Pound-2.0.tgz
tar xzvf Pound-2.0.tgz
cd Pound-2.0
sed "s/-o bin -g bin //g" < Makefile.in > Makefile.in.new
mv Makefile.in.new Makefile.in  # Hit y to override any restrictions
./configure --with-ssl=/usr/local/etc/openssl/ --prefix=/usr/local
make
sudo make install

5. Generate an ssl certificate.

cd /usr/local/etc

You can put the next line in ~/.bash_profile if you want openssl available everytime you open the terminal.

export PATH="/usr/local/etc/openssl/bin:$PATH"
sudo openssl/bin/openssl req -x509 -newkey rsa:1024 -keyout our_cert.pem \\
    -out our_cert.pem -days 365 -nodes

Fill out the required information to generate the ssl certificate.

6. Create a pound.cfg file.

cd /usr/local/etc # You should already be here

This next piece uses a trick called a heredoc. Instead of copying and pasting the below command into terminal, you could also just copy and paste the text into pound.cfg in /usr/local/etc/pound.cfg

cat > ~/tmp_file <<EOF
ListenHTTP
  Address 0.0.0.0
  Port    80
  Service
    BackEnd
      Address 127.0.0.1
      Port    3000
    End
  End
End

ListenHTTPS
  Address 0.0.0.0
  Port    443
  Cert    "/usr/local/etc/our_cert.pem"
  # pass along https hint
  AddHeader "X-Forwarded-Proto: https"
  HeadRemove "X-Forwarded-Proto"
  Service
    BackEnd
      Address 127.0.0.1
      Port    3000
    End
  End
End
EOF
sudo mv ~/tmp_file ./pound.cfg

7. Make sure that pound works.

pound -v -c

You should see Config file /usr/local/etc/pound.cfg is OK.
If not, make sure that you copied your config file correctly
using ‘cat pound.cfg’ to view what is in the file.

8. Turn off apache (assuming it’s running).

sudo apachectl stop

9. Turn on pound.

sudo pound -v

10. Start mongrel/webrick/lighty.

cd ~/work/my_killer_app
mongrel_rails start # Or ruby script/server (if you're still on lighty/webrick)

11. Marvel at your wonderous creation by pointing your browser to http://localhost/ or https://localhost/

TODO (feel free to do these and post how to do them in the comments):

• Make pound start when the computer loads.
• Use darwin ports to install zlib and openssl, but not pound.

I am broken! I should be below the text that is to my left.

As you can see, the code above is definitely broken. To fix this problem, we need only insert a <br style="clear:both;" /> at the bottom of the div. Look now:

I am fixed! The crazy floating text plagues me no more.

Let’s look at an example of user behavior to see why:

1. The user types http://superapp.com/account/logged_in into their browser.
2. This url is protected to the user is redirected to http://superapp.com/account/login and /account/logged_in is stored in session[:jump_to].
3. The user gets confused, lost, or just behaves like a typical user and navigates somewhere else.
4. Sometime later, the user goes to http://superapp.com/account/login and logs in.
5. The user is taken to ‘/account/logged_in’ instead of ‘account/welcome’. The user is confused.

Though user confusion on its own is bad, this still may not seem like much of a problem. So the user gets redirected to a different url than usual, how bad is that? In the app I’m currently working on, this behavior can be very bad. Depending on how the user is coming to the site and logging in, a bad return url can cause significant confusion to the user.

To fix this problem, the flash should be used instead of the session. Though the flash technically is the session, it is automatically cleared after each request. This prevents time sensitive data such as redirection urls from being stored longer than necessary and guarantees that you do not confuse your user with seemingly different points of entry on login.

[Model.find(1), Model.find(2), Model.find(3)] -
  [Model.find(1)] != [Model.find(2), Model.find(3)]

This does not behave as you would expect, because array subtraction compares elements on their object ids. Each find generates a new object, with a new id, so subtraction does not work. To get the behavior desired, do this instead:

to_be_removed = [Model.find(1)].map{|m| m.id}
[Model.find(1), Model.find(2), Model.find(3)].
  delete_if{|m| to_be_removed.include?(m.id)}

It’s not as beautiful, but it gets the job done.