Git Untrack Already Tracked Files

To remove files that are currently being tracked by git, you have to remove them from the “cache”. Note, doing this will NOT delete the file on your local machine. It will still be there but not be tracked.

 git rm -r --cached supersecretpasswords.txt 

You then need to add the file to the .gitignore file in the root of the project so that it isn’t tracked again on your next commit.

vim .gitignore
supersecretpasswords.txt

.gitignore files are tracked so remember to check in these changes.

git commit -am'my super secret passwords are safe!'

If you want to completely delete the file, on your local machine and from git

git rm supersecretpasswords.txt

If you’re working with a directory remember to add the -r flag for recursive removal!

Setting Up Users, Permissions and Groups for SSH Access to a Shared Git Repository

If you are having permission problems using git, such as

error: insufficient permission for adding an object to repository database ./objects

There are a couple thing you can do to remedy the situation, before moving to a full on git server like gitosis.

Create your users and add them to a group. Create (if you haven’t already) your git repo on the server and change permission and ownship and set the git config sharedRepository to true.

Here are all the commands, quick and dirty!

adduser sean
adduser jackson
groupadd developers
adduser sean developers
adduser jackson developers

mkdir -p /git/dev/app.git
cd /git/dev/app.git
git --bare init
vim description  #edit this file (mac os x complains otherwise)
chmod -R g+ws *
chgrp -R developers *
git repo-config core.sharedRepository true

Found from: http://mapopa.blogspot.com/2009/10/git-insufficient-permission-for-adding.html

Installing and Using Rvm on Mac OS X, Creating Gemsets and Reverting to Original Environment

What is RVM and why should you use it? RVM is a Ruby interpreter, version management tool. In short, it enables you to switch between different versions and releases of Ruby (for instance, version 1.8.6, 1.8.7, jruby 1.9.2, ruby enterprise edition) on the same machine, while associating different gems with each version of the ruby interpreter. This is super useful and awesome. If you want to play with Rails 3 and Ruby 1.9.1, for 5 minutes, and then want to switch back to your production apps, which are running on Rails 2.3.5 and Ruby 1.8.7, you can do so with a single command from the terminal. With RVM this is a fairly simple process so there is no reason not to install it. You can also revert back to your system settings (not using RVM) with a single command. After all Rails is just a gem, so you can easily create and manage different RVM “gemsets”, (sets of different gems), for the different versions of Ruby (rubies as RVM refers to them) you have installed.

Installing RVM

bash < <(curl -s https://rvm.beginrescueend.com/install/rvm)

Next you have to add rvm to your bash profile

# place in ~/.bash_profile as the very last line
[[ -s "$HOME/.rvm/scripts/rvm" ]] && . "$HOME/.rvm/scripts/rvm"

To check everything went well

type rvm | head -n1

Should tell you “rvm is a function”

How to add ruby, pass it the version to install

rvm install 1.8.7

*The current terminal session will load this environment. New sessions will not. To use a version of ruby and set it as the default, pass it the –default option

rvm use 1.8.7 --default

Next create a gemset, which will make available different gems for different versions

rvm gemset create rails_2_3_5

When you run “gem list”, you should see nothing!

gem install rails -v=2.3.5

Set a default rvm and default gemset, specify which gemset with the @ sign and include the –default option

rvm use 1.8.7@rails_2_3_5 --default

which gem
gem list
ruby --version
rails --version

And to get back to where you started and revert to using your original ruby setup

rvm system

For upgrading your version of RVM check out this post I wrote http://seanbehan.com/ruby/how-to-upgrade-rvm-on-mac-os-x/

Finally, you can create a .rvmrc file and put it in any directory and when you cd into that directory the environment specified in the file will be loaded automatically. This way you don’t have to remember the version and gemsets and type them into the console. All you have to do is put the ruby version and gemset name in the file like so

ruby1.8.7@rails2.3.5

You’ll be prompted to trust the .rvmrc file the first time, type “y” for yes. Also, subdirectories will inherit this .rvmrc so you can just put it in the parent directory like

rails2/
     .rvmrc
     app1
     app2
rails3/
     .rvmrc
     app1
     app2

And both app1 and app2 will use the .rvmrc environment while your rails3 directory apps will load the environment in its directory!

More information available here:
http://rvm.beginrescueend.com/rvm/install/
http://www.stjhimy.com/posts/4
http://eddorre.com/posts/installing-rails-3-beta-4-using-rvm

Defining Application Constants for Ruby on Rails Application

The best place to keep application constants which are environment specific is in config/environments directory. For instance…

# in RAILS_ROOT/config/environments/development.rb
APP_DOMAIN = "localhost"
# in RAILS_ROOT/config/environments/production.rb
APP_DOMAIN = "real-domain.com"

…will set the APP_DOMAIN constant to either “localhost” or “real-domain.com” depending on which environment Rails boots up.

Output Logger and SQL to the Rails Console in Development Mode

If you want to take a look at the SQL being generated by active record while your using the console, you can either type this into the console when it loads

ActiveRecord::Base.logger = Logger.new(STDOUT)

Or you can add it to your environment so that it’ll be the default behavior
rails_root/config/environments/development.rb

#...
ActiveRecord::Base.logger = Logger.new(STDOUT)

It’s a nice way to keep you away of any expensive queries you may unknowingly be writing!

Installing Scala on Mac OS X Leopard

I followed the instructions from here http://arvinderkang.com/2009/09/01/installing-scala-on-snow-leopard/ but I used version 2.7.6 (rather than .5) I installed scala under /usr/local/scala so I had to include it to my path. Type

vim .bash_profile
export PATH="/usr/local/bin:/usr/local/sbin:/usr/local/scala/scala-2.7.6.final/bin:$PATH"

Now to download and install…

curl -O http://www.scala-lang.org/downloads/distrib/files/scala-2.7.6.final-installer.jar
sudo java -jar scala-2.7.6.final-installer.jar

This will launch an installer. Just follow the instructions and when it asks for the destination folder, remember that it’s in /usr/local/scala
Simple as pie!

Manage Sinatra Server in Development Mode with Shotgun

Sinatra won’t reload your files. So if you’re developing your app and want to see any changes made in the browser, install the shotgun gem.

gem install shotgun

You can then use shotgun to run your server

shotgun your_sinatra_ditty.rb

Presto, your ditty will never be out of key :)

Installing Sphinx Search Engine on Mac OS X… or ld: library not found for -lmysqlclient

If you are trying to install Sphinx on Mac OS X, it will most likely fail. The current version of MySQL bundled with Mac OS X is not supported and therefore, it will spit out the error message because it can’t find the correct libraries.

 ld: library not found for -lmysqlclient

There is a quick solution to the problem -upgrade mysql! You’ll need Mac Ports installed, available at

http://macports.org/

Run the command

sudo port install mysql5

This will not destroy any existing data from your previous MySQL installation. The mac port installation will take a while, and it will appear as if it is just hanging. It’s not. It just takes a while. I clocked it at 15 minutes on a relatively fast network connection. Drink a cappuccino!

After you have the upgrade you’ll need to download Sphinx available at:
http://sphinxsearch.com/downloads.html (latest stable) and build the Sphinx engine from source like so:

wget http://sphinxsearch.com/downloads/sphinx-0.9.8.1.tar.gz
tar xzvf sphinx-0.9.8.1.tar.gz
cd  sphinx-0.9.8.1/
./configure --with-mysql-libs=/opt/local/lib/mysql5/mysql/
--with-mysql-includes=/opt/local/include/mysql5/mysql/
make
sudo make install

Much thanks to this post b/c I spent forever trying to get the bundled version of MySQL linked properly:

http://www.fozworks.com/2008/9/5/rake-installation-of-sphinx-in-mac-osx

Postfix, ActionMailer and OpenSSL Fix on Ubuntu

If you run into problems using ActionMailer > 2.2, Postfix and OpenSSL while sending mail from your application, try changing the following:

  vim /etc/postfix/main.cf

Change

 smtpd_use_tls=yes

to

smtpd_use_tls=no

OpenSSL support with Postfix does not work out of the box. You can either generate valid certificates or tell Postfix not to use the certificates. More information is available in this discussion forum.

http://forum.slicehost.com/comments.php?DiscussionID=2656

Sending eMail with Rails on Mac OS X Development Environment

You’ll need a mail transport agent (MTA). I installed and used postfix using Mac Ports.

sudo port install postfix

You’ll need to start postfix, to send mail from your Rails application. You can set it as a startup item and it will start on boot. However, since I don’t send too much mail from my Rails app, just for testing normally, I start it manually.

sudo postfix start

That should do it!