Setting up an Ubuntu 10.10 laptop for LAMP development

I’m blogging this mostly for my reference as I occasionally reinstall my laptop and always forget the steps to get back to a good state.

Aim:

• Ubuntu Linux 10.10 desktop
• Apache 2.2
• MySQL 5.1
• PHP 5.2

Firstly, install Ubuntu 10.10. Make sure you opt to encrypt your home directory. While this means it’s difficult to recover contents of your home directory in the event of an OS crash, it’s also means you can sleep at night knowing that if you lose your laptop you haven’t lost your intellectual property. The system overhead for doing this is not really noticable. The down side of this is that you cannot access the files unless you’re logged on (see the bit later about the projects directory and Apache).

Now, let’s install Apache, MySQL and PHP. Note that I’m installing some extra packages that I need for my development purposes.

bob@bob-laptop:~$ sudo apt-get install libapache2-mod-php5 mysql-server php5-mysql
bob@bob-laptop:~$ sudo apt-get install php5-curl php-pear  # some extras I use
bob@bob-laptop:~$ sudo apt-get install openssh-server subversion bzr  # some extras I use

During the installation of those packages you’ll be asked for a password for the MySQL root user. I always use “root” for my convenience. You can use whatever you like. This user does not have root access to the system, but will have full access to the MySQL databases. By default MySQL only listens on the localhost interface so an insecure password like “root” is acceptable for my purposes. You’ll see later that we can shift certain databases to reside on the encrypted home directory if that’s important to you.

Set up the projects directory

I like to keep all my web stuff in a subdirectory of my home directory called projects. The full path to that will be /home/bob/projects. In order to be able to browse these projects with Apache I’ll put a symlink in /var/www (Apache’s default web root directory) to it.

Here’s a terminal session where I create the projects directory.

bob@bob-laptop:~$ mkdir ~/projects
bob@bob-laptop:~$ sudo ln -s ~/projects /var/www/projects
bob@bob-laptop:~$ ls -l /var/www
total 4
-rw-r--r-- 1 root root 177 2011-12-11 15:30 index.html
lrwxrwxrwx 1 root root  18 2011-12-12 21:25 projects -> /home/bob/projects

Great. But now if you try to access http://localhost/projects you’ll get a 403 Forbidden page. This is because Apache isn’t able to see your home directory. A small tweak will fix that.

bob@bob-laptop:~$ chmod o+x ~

Note that this command will allow any other user (of which Apache’s www-data is one) on your system to see the files in your home directory. For me this isn’t an issue as I’m the only user on my system.

Now if you revisit http://localhost/projects you’ll get a directory index instead of a 403 Forbidden page. You can now create files in /home/bob/projects (or whatever your user name is) and Apache will be able to serve them up to your web browser.

Note that because we opted to encrypt the home directory, the /home/bob directory is only mounted when bob logs in. This means that if you boot your system and try to access it over the network without being logged in, you’ll likely get a 403 Forbidden or 404 Page Not Found error for any URL in /projects. Other files can be placed in /var/www/whateveryoulike and will be accessible regardless.

Example:

bob@bob-laptop:~/projects$ cat > phpinfo.php
<?php phpinfo(); ?>

(press Ctrl-D after typing the phpinfo() line to save the file)

Now if you browse to http://localhost/projects/phpinfo.php you will get the standard PHP Information page.

Using an encrypted database

We’re not so much using an encrypted database as we are moving it onto an encrypted file system. We use the same trick that we used for Apache but we’re doing this for MySQL. Note that while it is possible to have all databases encrypted, you will need to make sure you log on first before you start MySQL. Here I will just encrypt one database:

-- Create a mysql directory in my home dir.
bob@bob-laptop:~$ mkdir ~/mysql

-- Create a sample mysql database called 'secure'
bob@bob-laptop:~$ mysqladmin -uroot -proot create secure

-- Stop the mysql service
bob@bob-laptop:~$ sudo stop mysql
mysql stop/waiting

-- Move the newly created 'secure' database to my home dir
bob@bob-laptop:~$ sudo mv /var/lib/mysql/secure ~/mysql

-- Create a symbolic link for mysql to use
bob@bob-laptop:~$ sudo ln -s ~/mysql/secure /var/lib/mysql/secure

-- Start mysql again
bob@bob-laptop:~$ sudo start mysql
mysql start/running, process 2778

-- Now access the database in the new place
bob@bob-laptop:~$ mysql -uroot -proot
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 34
Server version: 5.1.49-1ubuntu8.1 (Ubuntu)

Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
This software comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to modify and redistribute it under the GPL v2 license

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> use secure;
Database changed

No errors – the connection was successful. Again the same thing applies in that you can only access this database while you are logged on.

.htaccess files (optional, but recommended)
Out of the box, Apache won’t read .htaccess files. To enable these permanently for all directories under your /var/www directory (including the project directory), edit the /etc/apache2/sites-enabled/000-default file (as root) and change line 11 to say “AllowOverride All” (instead of None).

mod_rewrite (optional, but recommended)

Also, you may want to enable mod_rewrite as many web applications use this to generate nice looking URL’s.

bob@bob-laptop:~$ sudo a2enmod rewrite
bob@bob-laptop:~$ sudo apache2ctl restart

xdebug plugin for PHP

The xdebug plugin gives you nice stack traces and formatted var_dump()s which makes it easier to develop. It also comes with breakpoints, remote debugging and a range of other things. Check out the whole shebang at http://xdebug.org/.

Installation is simple:

bob@bob-laptop:~$ sudo apt-get install php5-xdebug

Restart Apache for the change to take effect (sudo apache2ctl restart).

Enabling display of errors in your browser

By default PHP ships with display_errors = Off. This is a requirement for a production system but it will drive you nuts on a development box. When off, any errors are logged to Apache’s error_log file in /var/log/apache.

To turn it on, edit the file /etc/php5/apache2/php.ini and look for the lines like this:

display_errors = Off
display_startup_errors = Off
html_errors = Off

And change them all to “On”. Again, restart Apache for the change to take effect (sudo apache2ctl restart).

Happy developing!

Consistency

Warning: this may be the most valuable blog post you ever read.

I’ve been developing for a long time – the first programs that I first wrote that other people were using was back in 1992. At the time, I was the only one working on the code and there was no reason for others to get involved. In fact back then it seemed that we were driven by one-upmanship and sharing code was almost unheard of, unless you had to get an assignment in the next day and you had some stupid reason for not being able to complete it, then someone might take pity on your ass and bail you out. Back then, consistency wasn’t important – what mattered was whether the code ran or not. Even better if it ran and you got paid.

If there’s one thing I could share with you about my experiences over the last twenty years, I would have to say that it’s this. Be consistent.

Consider the following code:

<?php
  $query = 'select * from customer where id = 123';
  $result = mysql_query($query);
  $row = mysql_fetch_assoc($result);
  $identifier = $row['id'];
  echo $identifier;
?>

We’re fetching a row from a table and echoing out the id field. The code above doesn’t really matter, but what does matter is the inconsistency. Can you spot it?

The inconsistency is that the field in the database is called “id” and we put it into a variable called $identifier. This does not break the code, but it does mean that you have just introduced an inconsistency that will bite you.

That’s a pretty simple example, but imagine those kind of differences across an entire application, a database schema or even your whole organisation. It happens, and all too frequently.

The consistency issue isn’t a coding style issue – let me be very clear on that – it’s more a culture issue. You need to work hard to spot these inconsistencies in your organisation and nip them in the bud really early. And they may not appear in code either. You can find them anywhere from code, to documentation, to common usage in discussions in the workplace.

If you let these inconsistencies propagate you’re going to have to deal with them time and time again. Here’s a real world example: I am dealing with a system at the moment where products are identified by their SKU number (Stock Keeping Unit). This number has been referred to as the following in various places (code, documentation, wiki pages, emails etc):

• ItemCode
• ItemId
• Item_Id
• ItemID (yes, case makes a difference!)
• ItemSKU
• Identifier
• Identifer (yes, misspelling of Identifier)
• ProductId
• ProductSku
• SKU

The boat has sailed on that one – there is no way that this situation could be wrestled under control, you’ll have to do what you can if you come across this. But if you have the luxury of a fresh project then it’s time to gather your troops and spell it out on the board – CONSISTENCY. Drum it into your processes and procedures, your code reviews and commit messages. There’s no excuse for any inconsistency at all – especially when it will cost you in time chasing bugs because the value isn’t turning up like it should or the record isn’t saving.

If you haven’t already I highly recommend putting together some coding standards for your company – or even for yourself. And follow them to the letter. It doesn’t really matter what style of indenting you use (K&R, Allman, BSD KNF, Whitesmiths etc) – what matters is that you’re … you know what I’m going to say don’t you.

Feel free to borrow from the Turboweb Coding Standards (which in turn were based on the Drupal Coding Standards). Make sure that your new starts read your coding standards and understand them. And take time to teach them well.

Addendum: Ironically I managed to misspell the title of this blog post, I’ve now corrected it but as the link is out and about on various social media sites I can’t change that, therefore if you’re viewing this post by itself you’ll see that the URL says “consitency”

Using the Grid plugin in Compiz

Recently I’ve been introduced to the Grid plugin in Compiz – this is a fantastic little plugin that snaps your windows to predefined positions on the screen. After using it for the last couple of weeks I can’t imagine going back to not using it.

To get access to it you will need to install the compiz settings manager, and load Compiz’s “Fusion Plugins Extra”:

sudo apt-get install \
    compizconfig-settings-manager \
    compiz-fusion-plugins-extra

Once you’ve done this simply enable it:

1. System, Preferences, CompizConfig Settings Manager
2. In the Filter box in the top left, type in “grid”
3. Tick the box to enable it and click “Close” (bottom left)

Now try using Ctrl-Alt and numbers on your keypad. CA-9 will snap a window into the top right corner (press it a few more times to get different sizes) and CA-8 will make it snap to the top half of the screen (the number is the position on the screen, you’ll get the gist of it).

Check out this demo video:

Happy Ubuntuing!

Mosgiel Centenary Celebrations – 1985.

I recalled an event I participated in back in 1985 which was the Mosgiel 100 year centenary parade. As a pupil of one of the local primary schools (Reid Park Primary) we were primed with dress of the era and a song that was nowhere near as bad as some radio jingles. We got to ride on a float down the main street, oh what joy!

“I’m a hundred year old kid – don’t you see,
I’m proud to see the end of our first century.
From 1885 through ’til 1985,
We’ll still be century children at our next centenary.”

Author unknown, can you help?

Walk To Work Day

Today was Walk To Work Day in Dunedin, an initiative spearheaded by Living Streets Aotearoa with the support of Sport Otago and the DCC. I decided to make the trip as the amount of excercise I get thanks to the extreme convenience of my scotter is minimal. I left home at 7:20 this morning and arrived in the Octagon at about 8:30 where a few stands were laid out for registration. The registration process was rewarded with a $7 voucher redeemable at Barakah, MASH, The Ra Bar, Alibi or The Craic. I chose MASH and a nice looking breakfast bap which was delicious, but unfortunately my order was forgotten in the rush of breakfast time cafe operations. After a reminder it turned up with an apology.

They say New Zealand is a small place and indeed it is – I ran into community advocates Frank Buddingh and Nina Arron from Lawrence who were on the registration stands. A familiar face was very much a welcome sight. I first ran into Frank and Nina some time ago when Frank was looking for an alternative provider for the Buddingtree Consultancy website.

For me the nicest thing (other than the fantastic weather!) about walking into town was it was a chance for me to “sit down” and listen to some podcasts. Listening to Leo Laporte, Jono Bacon and Randal Schwartz interview Jamie Cameron about Webmin on the FLOSS weekly podcast was a delight, especially as in my dark days I had a fair use for Webmin, so much so that I bought Jamie’s “Using Webmin” book.

Now that I have my walking method sussed all I need to do is load up my iPod and get an early night and a good sleep beforehand – unfortunately the early night and good sleep was thwarted last night by some jQuery and AJAX goodness and also by Zoe night-babbling, then Linus who woke up crying because “Ada ate my pie in a dream!” and then some more Zoe babbling. Things had quietened down by about 4am anyway.

Check out the local Channel Nine TV coverage at http://www.ch9.co.nz/node/14223

Installing MagentoCommerce – problems

MagentoCommerce is an open-source enterprise level ecommerce system suitable for high end ecommerce websites. We’re in the throes of developing a large solution for a local company, and the developers involved in provisioning the site are installing local copies of Magento on their Apache servers to test with.

Here’s a list of issues that I’ve come across with installing Magento, and how I’ve solved them. For the record I’m using Magento 1.3.2.2 (released 19.07.2009)

1. Can’t get past the second install step

This is the step that asks you for your database password. If the database you’re specifying doesn’t exist then you can’t proceed. I’m sure there’s a bug here because it’s like an error message isn’t displayed. Would love to dig into this but our project is on a tight time frame. MAKE SURE YOU CREATE THE DATABASE YOURSELF FIRST (no tables required).

2. Can’t log in after installation

If after logging in you go to the /admin directory and you can’t log in, it’s probably because of the URL that you used to install it. I tried installing it to http://localhost/, http://127.0.0.1/ and http://192.168.2.10/ (my IP) all with the same result. After googling it seemed to be something to do with Magento refusing to set a cookie for a top-level domain (or somesuch). Workarounds are to use a host name that has a dot in it, e.g. http://localhost.localdomain/ (or in my case, http://bob-desktop.local). Add this to your hosts file, you may have to restart your browser for it to pick it up.

3. Firefox keeps asking you to download a PHTML file.

After doing a completely fresh install of Apache2, PHP5, mysql, Magento etc on a fresh machine (Ubuntu 9.04, Firefox 3.0.11) Firefox kept asking me what I wanted to do with the PHTML file when accessing the freshly untarred Magento directory. It took me ages to find an answer to this, but it was as simple as clearing your cache in Firefox. I dicked around with the Apache configuration, permissions, .htaccess files etc and finally found a comment about the Firefox cache.

4. AllowOverride All

Magento uses a .htaccess file in the root directory. I noticed that the default for /var/www is AllowOverride None which prevents Apache from looking at the content of .htaccess files. While this didn’t cause me trouble, I did set it to “AllowOverride All” while trying to solve #3. The file is /etc/apache2/sites-enabled/000-default, line 11. Note there may be security implications of doing this if you’re the administrator of a shared hosting environment and as such you should read about the AllowOverride directive.

Installation requirements:

From a stock Ubuntu 9.04 machine I had to install the following packages to support Magento:

• libapache2-mod-php5
• php5-curl
• php5-mcrypt
• php5-mysql
• php5-gd
• mysql-server

Also, I have this command on standby to reset the Magento environment back to scratch (deletes the magento directory, drops the database, untars the source file and creates the empty database again)

cd /var/www ; rm -Rf magento ; tar xvfz /home/bob/magento-1.3.2.2.tar.gz ;
   chmod -R a+rw magento ; mysqladmin -uroot -proot -f drop magento ;
   mysqladmin -uroot -proot create magento

That’s all for now.