WordPress¶

Deploy the stack¶

WordPress usually runs on PHP + MySQL. Therefore, we will need to deploy a PHP service and a MySQL one:

$ dotcloud deploy -t php louis.wordpress
$ dotcloud deploy -t mysql louis.mysql

Download and configure WordPress¶

Download WordPress, and unzip it:

$ wget http://wordpress.org/latest.zip
$ unzip latest.zip

Everything should have been decompressed into a “wordpress” directory.

We need to edit “wp-config.php” to configure the database, some magic WordPress variables, and the language of your blog.

First, retrieve your database parameters with the following command:

$ dotcloud info louis.mysql
cluster: wolverine
config:
    mysql_password: U9a6FgZ3
deployment: sanfran
name: sanfran.db
ports:
-   name: mysql
    url: mysql://root:U9a6FgZ3@mysql.louis.dotcloud.com:1234
-   name: ssh
    url: ssh://dotcloud@mysql.louis.dotcloud.com:1235
type: mysql

Copy wp-config-sample.php to wp-config.php, and open the wp-config copy in your favourite editor.

Edit the following lines:

/** The name of the database for WordPress */
define('DB_NAME', 'mysql');

/** MySQL database username */
define('DB_USER', 'root');

/** MySQL database password */
define('DB_PASSWORD', 'U9a6FgZ3');

/** MySQL hostname */
define('DB_HOST', 'mysql.louis.dotcloud.com:1234');

A little farther in the wp-config.php file, you will see a section similar to the following one:

define('AUTH_KEY',         'put your unique phrase here');
define('SECURE_AUTH_KEY',  'put your unique phrase here');
define('LOGGED_IN_KEY',    'put your unique phrase here');
define('NONCE_KEY',        'put your unique phrase here');
define('AUTH_SALT',        'put your unique phrase here');
define('SECURE_AUTH_SALT', 'put your unique phrase here');
define('LOGGED_IN_SALT',   'put your unique phrase here');
define('NONCE_SALT',       'put your unique phrase here');

Point your browser to https://api.wordpress.org/secret-key/1.1/salt/ (or just run “curl https://api.wordpress.org/secret-key/1.1/salt/”) and use the lines generated by the online service.

Add DotCloud specific files¶

WordPress will need to create all sorts of files while it is running: when you upload a media file, but also if you install a plugin through the web administration interface.

If we don’t do anything special, those files will be erased each time you do a new “dotcloud push”. We could chose to never do “dotcloud push” again, but that would bar you from leveraging all the power of DotCloud, should you decide to tweak or scale your blog. So let’s see how we can work around that.

We are lucky, because all those files are located under the “wp-content” subdirectory. So we just have to take care about this specific directory. Create the following script, “wordpress/postinstall”:

#!/bin/sh
if [ -d ~/data/wp-content ]
then
      rm -rf ~/current/wp-content
else
      mkdir -p ~/data
      mv ~/current/wp-content ~/data/wp-content
fi
ln -s ~/data/wp-content ~/current/wp-content

The “postinstall” script is run each time you push your code to DotCloud. The first time, it will move the “wp-content” directory in a safe place (straight under /home/dotcloud), and replace it with a symbolic link. From the second time you push (and onwards), the symbolic link will just be recreated.

Don’t forget to set this script as executable:

$ chmod +x wordpress/postinstall

If you want to enable nice permalinks (i.e., http://www.myblog.com/my-post instead of http://www.myblog.com/?p=123), you also have to create the file “wordpress/nginx.conf” with the following line:

try_files $uri $uri/ /index.php;

Push your WordPress install to DotCloud¶

Just run the following (from the wordpress directory):

wordpress$ dotcloud push louis.wordpress .

Then go to http://wordpress.louis.dotcloud.com/: you will be prompted to create the admin user for your blog.

Your blog is ready!

Nicer permalinks¶

Note that you can give your permalinks any syntax you like. You can use http://wordpress.louis.dotcloud.com/index.php/2011/02/19/sample-post/ but you can also strip out the “index.php”. Just go to the permalinks settings in the dashboard, use the custom setting and put “/%year%/%monthnum%/%day%/%postname%/” there, for instance.

Plugins installation and setup¶

You can safely install WordPress plugins from the admin dashboard. The PHP code for the plugins is downloaded into the “wp-content” directory, which will not be touched by “dotcloud push”, thanks to our custom postinstall script.

WordPress upgrades¶

If you perform a WordPress upgrade through the online dashboard, it will be undone next time you do a “dotcloud push”. The preferred way to upgrade is to:

• fetch the latest source zip,
• uncompress it,
• copy over wp-config.php, postinstall and nginx.conf,
• “dotcloud push” the new directory.