Lion comes with Apache and PHP installed. We just need to enable PHP, install MySql and create a database, then download drupal.

Enable PHP

My new laptop which came with Lion has PHP 5.3.15, using the test page we’ll build below you can verify you’ve got a good version of PHP to go with the Drupal you need:

• Drupal 6: PHP 4.4.0 or higher (5.2 recommended).
• Drupal 7: PHP 5.2.5 or higher (5.3 recommended).
• Drupal 8: PHP 5.3.10 or higher.

Commands below use vi (of course, you should use your editor of choice). (thank you stackoverflow)

You’ll need sudo to edit the Apache config file:

 
sudo vi /etc/apache2/httpd.conf

uncomment the following line:

LoadModule php5_module libexec/apache2/libphp5.so

On the following line change _www to the username you log in with:

User _www

By default, Apache only loads index.html, so update that line to:

DirectoryIndex index.html index.php index.htm

Restart apache on the command line

sudo apachectl restart

Now, let’s make a test file:

cd ~/Sites
mkdir php-test
cd php-test/
vi index.php

Then paste in this test file and browse to http://localhost/~yourusername/php-test/

Install MySql

I like to install everything with homebrew which is my favorite package manager for osx. It keeps everything in /usr/local/ by default, and then I don’t have to remember where GUI installers put everything.

 
brew install mysql

I like to have MySql always start up, so I use a Launch Agent, which homebrew describes how to do after the install:

To have launchd start mysql at login:
    ln -sfv /usr/local/opt/mysql/*.plist ~/Library/LaunchAgents
Then to load mysql now:
    launchctl load ~/Library/LaunchAgents/homebrew.mxcl.mysql.plist
Or, if you don't want/need launchctl, you can just run:
    mysql.server start

Now make a database:

mysqladmin -uroot create drupal_dev

The default way this is set up is for a dev environment, so there’s no password and root has full access. You can see this in the mysql console:

mysql -uroot
show databases;
show grants;

Now we need to fix the PHP configuration to refer to mysql correctly so we don’t get PDO errors (thanks Hiraash):

sudo cp /etc/php.ini.default /etc/php.ini
vi /etc/php.ini

replace all instances of /var/mysql/mysql.sock with /tmp/mysql.sock
and restart apache

sudo apachectl restart

Download Drupal

I followed the drupal.org instructions, but you need to go find the right version. As of this writing, 7.22 is the recommended v7 release, which is what I’ll be working with.

cd ~/Sites
wget http://ftp.drupal.org/files/projects/drupal-7.22.tar.gz
tar -xzvf drupal-7.22.tar.gz
rm drupal-7.22.tar.gz

Now, I’ll just rename it to be the same name as the database we set up:

mv drupal-7.22 drupal_dev

browse to http://localhost/~yourusername/drupal-dev and proceed with the install wizard

step through the wizard and drupal sets itself up.