Set up a web server on your Pi and install WordPress

Apache is a popular web server application you can install on the Raspberry Pi to allow it to serve web pages.

On its own, Apache can serve HTML files over HTTP, and with additional modules can serve dynamic web pages using scripting languages such as PHP.

First install the apache2 package by typing the following command into the terminal:

sudo apt-get install apache2 -y

By default, Apache puts a test HTML file in the web folder. This default web page is served when you browse to http://localhost/ on the Pi itself, or http://192.168.1.10 (whatever the Pi's IP address is) from another computer on the network. To find out the Pi's IP address, type hostname -I at the command line (or read more about finding your IP address).

Browse to the default web page, either on the Pi or from another computer on the network, and you should see the following:

This means you have Apache working!

This default web page is just an HTML file on the filesystem; it is located at /var/www/index.html. Navigate to this directory in the terminal and have a look at what's inside:

cd /var/www
ls -al

This will show you:

total 12
drwxr-xr-x  2 root root 4096 Jan  8 01:29 .
drwxr-xr-x 12 root root 4096 Jan  8 01:28 ..
-rw-r--r--  1 root root  177 Jan  8 01:29 index.html

This shows that there is one file in /var/www/ called index.html. The . refers to the directory itself /var/www/, and the .. refers to the parent directory /var/.

1. The permissions of the file or directory
2. The number of files in the directory (or 1 if it's a file)
3. The user who owns the file or directory
4. The group which owns the file or directory
5. The file size
6. The last modification date and time

As you can see, by default the www directory and index.html file are both owned by the root user. In order to edit the file, you must gain root permissions. Either change the owner to your own user before editing (using sudo chown pi: index.html), or edit with sudo (using sudo nano index.html).

Try editing this file and refreshing the browser to see the web page change.

PHP is a preprocessor; it's code that runs when the server receives a request for a web page. It runs, works out what needs to be shown on the page, then sends that page to the browser. Unlike static HTML, PHP can show different content under different circumstances. Other languages are capable of this, but since WordPress is written in PHP, that's what we need to use this time. PHP is a very popular language on the web; large projects like Facebook and Wikipedia are written in PHP.

Install the PHP and Apache packages with the following command:

sudo apt-get install php5 libapache2-mod-php5 -y

Now move the index.html file to index.php:

sudo mv index.html index.php

Edit the file:

sudo nano index.php

Put some PHP content in it:

<?php echo "hello world";

Now save and refresh your browser. You should see "hello world". This is not dynamic but it is still served by PHP. Try something dynamic, for example:

<?php echo date('Y-m-d H:i:s');

Or show your PHP info:

<?php phpinfo();

MySQL (pronounced My Sequel or My S-Q-L) is a popular database engine. Like PHP, its overwhelming presence on web servers enhanced its popularity. This is why projects like WordPress use it, and why those projects are so popular.

Install the MySQL Server and PHP-MySQL packages by entering the following command into the terminal:

sudo apt-get install mysql-server php5-mysql -y

When installing MySQL you will be asked for a root password. You'll need to remember this to allow your website to access the database.

You can download WordPress from wordpress.org using the wget command. Helpfully, a copy of the latest version of WordPress is always available at wordpress.org/latest.tar.gz and wordpress.org/latest.zip, so you can grab the latest version without having to look it up on the website. At the time of writing, this is version 3.8.1.

Navigate to /var/www/, and download WordPress to this location. You'll need to empty the folder first (be sure to check you're not deleting files you need before running rm); change the ownership of this folder to the pi user too.

cd /var/www
chown pi: .
rm *
wget http://wordpress.org/latest.tar.gz

Now extract the tarball, move the contents of the folder it extracted (wordpress) to the current directory and remove the (now empty) folder and the tarball to tidy up:

tar xzf latest.tar.gz
mv wordpress/* .
rm -rf wordpress latest.tar.gz

Running the ls or (tree -L 1) command here will show you the contents of a WordPress project:

.
├── index.php
├── license.txt
├── readme.html
├── wp-activate.php
├── wp-admin
├── wp-blog-header.php
├── wp-comments-post.php
├── wp-config-sample.php
├── wp-content
├── wp-cron.php
├── wp-includes
├── wp-links-opml.php
├── wp-load.php
├── wp-login.php
├── wp-mail.php
├── wp-settings.php
├── wp-signup.php
├── wp-trackback.php
└── xmlrpc.php

This is the source of a default WordPress installation. The files you edit to customise your installation belong in the wp-content folder.

To get your WordPress site set up, you need a database. Run the mysql command in the terminal and provide your login credentials (e.g. username root, password password):

mysql -uroot -ppassword

Here I have provided my password (the word password) on the command line; there is no space between -p and your password.

Alternatively you can simply supply an empty -p flag and wait to be asked for a password:

mysql -uroot -p

Now you will be prompted to enter the root user password you created earlier.

Once you're connected to MySQL, you can create the database your WordPress installation will use:

mysql> create database wordpress;

Note the semicolon ending the statement. On success you should see the following message:

Query OK, 1 row affected (0.00 sec)

Exit out of the MySQL prompt with Ctrl + D.

You need to find out your Pi's IP address to access it in the browser, so in a terminal type the command hostname -I.

Navigate to http://YOUR-IP-ADDRESS e.g. http://192.168.1.5 in the web browser on your Pi.

You should see a WordPress error page; this is good! Click the big button marked Create a Configuration File followed by the Let's go! button on the next page.

Now fill out the basic site information as follows:

Database Name:      wordpress
User Name:          root
Password:           <YOUR PASSWORD>
Database Host:      localhost
Table Prefix:       wp_

Upon successful database connection, you will be given the contents of your wp-config.php file:

Copy this text, return to the terminal on the Pi and edit the file with nano wp-config.php. Paste the text into this file, and save and exit with Ctrl + X, then Y for yes and Enter.

Now hit the Run the install button.

Now you're getting close.

Fill out the information: give your site a title, create a username and password, put in your email address and untick the search engines box. Hit the Install WordPress button, then log in using the account you just created.

Now you're logged in and have your site set up, you can see the website by visiting your IP address in the browser on the Pi or another computer on the network. To log in again (or on another computer), go to http://YOUR-IP-ADDRESS/wp-admin.

It's recommended that you change your permalink settings to make your URLs more friendly. To do this, log in to WordPress and go to the dashboard. Go to Settings then Permalinks. Select the Post name option and click Save Changes. After saving, you will be prompted to update your .htaccess file. You probably don't have one yet, so add one in /var/www/ by typing nano .htaccess; note this is a hidden file, so it starts with a dot. Then paste in the contents provided:

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

Save the file and return to the website homepage. Click on the post title or the sample page link and you'll probably see a Not Found error page. This is because the rewrite module has not been enabled in Apache. To do this, enter sudo a2enmod rewrite.

You'll also need to tell the virtual host serving the site to allow requests to be overwritten. Do this by editing the virtual host file (with root permissions): sudo nano /etc/apache2/sites-available/default; also, change the AllowOverride setting on line 11 (inside the <Directory /var/www/> block) from None to All. Save the file and then restart Apache with sudo service apache2 restart. Once it's restarted, refresh the page and it should load successfully. Now posts have URLs like /hello-world/ instead of /?p=123, and pages have URLs like /sample-page/ instead of /?page_id=2.

WordPress is very customisable. By clicking your site name in the WordPress banner along the top of the page (when logged in), you'll be taken to the Dashboard. From here you can change the theme, add pages and posts, edit the menu, add plugins and lots more. This is just a taster for getting something interesting set up on the Raspberry Pi's web server.