Jacob Redding

Alternative title: What every new Drupal developer should know

Over the past few years I've been teaching various Drupal classes ranging from introductory courses to module development courses for seasoned developers. In fact what lit a fire under me to write up this entry was an upcoming course I'm doing with Chapter Three December 14-18th in San Francisco. I'm my classes nearly every student has asked me a variation of the same question; What do I need to know?

If the student was a beginner I'd point them to one of the numerous Top X Drupal modules, such as Lullabot's Top 80, or direct them to review the awesome site showcases up on drupal.org. If the student was a developer (or aspiring developer) the answer was never as concrete. I would explain the concept of a hook, rattle off a few hooks I thought were important, point them to greggle's (or GVS's?) awesome Cheat sheet, tell them about t(), hook_menu, explain how db_query() worked, and then direct them to http://api.drupal.org. Being the geek I am this wasn't good enough for me so I set out to find out what the top hooks and functions were. I wanted something concrete.

I broke out my terminal and used CVS to checkout every module on drupal.org that was listed as stable for Drupal 6 (those in a DRUPAL-6 branch), 3,308 modules. I then wrote a quick and dirty BASH script that went through every function sorting, counting, and ultimately discovering what the most heavily used hooks were. I wrote this script over a year ago at a time when I was living behind the great firewall of China, which made blogging, twittering, and other fun Internet activities a frustrating experience, which is why I have not posted this sooner.
Without much further delay here are the top hooks used in Drupal 6:

The next 12 significant implementations are:

Most Utilized Functions

My curiosity then led me to answer the question: What are the most frequented used functions in a Drupal module?
A few commands later I discovered 143,783 unique functions used a total of 1,008,398 times across the 3,308 modules. Below is how these panned out.
Note: I removed uses of if, foreach, etc.

For the curious here are the BASH commands I ran to discover this information

The completely inefficient but written in roughly ten minutes BASH script I used to discover the top hooks was: --count_functions.sh--

#!/bin/sh
module_dir="/Users/jredding/Downloads/contributions/modules"
for module_name in `find $module_dir -name *.info|xargs basename |awk -F.info '{print $1}'`
do
grep -hr "function * ${module_name}_" *|awk -F${module_name}_ '{print $2}'|awk -F"(" '{print $1}'
done

I then piped the output through

sort |uniq -c |sort -n 

functions_tmp=/tmp/all_functions.txt
module_dir="/Users/jredding/Downloads/contributions/modules"
grep -hR "^function *" modules/* > $functions_tmp

for module in `find $module_dir -name *.info|xargs basename |awk -F".info" '{print $1}'`
do
  grep -h "function * ${module}_" $functions_tmp |awk -F${module}_ '{print $2}'|awk -F"(" '{print $1}'
done
rm $functions_tmp
~                 

To discover every function used I ran the following command:

find ./modules/ -exec awk '/[a-9]\(/ { for (i = 1; i <= NF; i++) printf "%s\n", $i }' {} \; |awk '/[a-9]\(/ {print}'|awk -F\( '{print $1}' |sort |uniq -c |sort

A few interesting stats

I found the following stats interesting.

Raw Data

Function use

Another Drupalcon has come and gone but our work is not over. A dedicated team is actively at work on Drupalcon Paris and another team is being formed to put on Drupalcon 2010. Drupalcon is built by and is for the community. They are what you want them to be. Help us shape the future of Drupalcon by taking a few minutes to answer the questions in the Drupalcon Survey.

Thanks to every one of the over 1,400 people that showed up in D.C, I hope that we can top that number in Paris and then again in 2010!