You might have read recently that composer made some changes to drastically improve performance of 'composer update' operations. Inspired by this I will give you further tips to make composer operations even faster. I will also cover a few other composer power user tips to make you even more productive when using composer.

1. Composer
Power User Tips
Tom Corrigan
Lead Developer - EstimateOne
@tommygnr
Melbourne PHP Users Group
January 2015

2. Composer just got way faster
• My biggest (and only) complaint about composer is
its speed
• One simple function call has slashed composer
update calls by up to %90
• gc_disable()
• See Anthony Ferrara’s brilliant explanation of how
PHP’s garbage collector works here: http://
blog.ircmaxell.com/2014/12/what-about-
garbage.html

3. First: What happens when you run
composer update
• Parses your composer.json
• Recurses through dependencies creating Rules for every possible version
• Recurses through the ruleset to determine installable versions
• Performance gets exponentially worse as package count increases
• Downloads updates/ new packages

4. Let’s find out why
• Running composer update for the packagist app
resulted in over 15 million function calls
• Lots of classes being created, lots of garbage
collector runs
• Except there were no circular references
• The garbage collector was wasting its time

5. Run composer with HHVM
$ hhvm /usr/local/bin/composer update
or create a simple wrapper
#!/bin/bash
hhvm /usr/local/bin/composer update -v "$@"

6. Speeding up download
• composer install --prefer-source will give you git
repositories rather than zipballs
• Use it for ongoing projects where you will be
running composer update often
• This isn’t faster the first time
• It will pay you back in spades subsequently

7. Bonus when installing from source
Tom@Toms-iMac:~/Sites/ascension (master)$ composer update -v
Loading composer repositories with package information
Updating dependencies (including require-dev)
- Updating phpunit/php-token-stream (1.3.0 => 1.4.0)
Checking out db32c18eba00b121c145575fcbcd4d4d24e6db74
Pulling in changes:
db32c18 - Sebastian Bergmann: Update the branch alias to 1.4
802c518 - Milad Rastian: Added tokens introduced in HackLang #43
- Updating mopa/bootstrap-bundle dev-master (184a761 => 32f5c47)
Checking out 32f5c47b575278236dbf28245cb26acbe1d1d5ea
Pulling in changes:
8be5b94 - auipga: Updated @icon-font-path
b500dde - auipga: make $icon-font-path able to override
fa3abea - Marc Valldepérez: added compatibility with symfony 2.3
98ff7b0 - Marc Valldepérez: added compatibility with label_format
Writing lock file
Generating autoload files
Tom@Toms-iMac:~/Sites/ascension (master)$
• composer update -v will
show you the commit
messages for all
changes
• this is extremely useful
when using unstable
deps

8. Tracking down bugs in third party
code
Scenario:
After running composer update your application
breaks. You track it down to a single library that was
upgraded from 1.0 to 1.1. There were 300 commits
between the two releases and the CHANGELOG
isn’t helpful.
How do you find which commit broke your app?

9. git bisect to the rescue
• Check the diff for your composer.lock file
• Find the SHA1 hash for the working version
$ git bisect start
$ git bisect bad #Current version is bad
$ git bisect good OLD_SHA1

10. git bisect to the rescue
• run your tests
• if they pass:
$ git bisect good
• if they fail:
$ git bisect bad
• repeat until you find the guilty commit

11. Fixing bugs in third party code
Scenario:
After bisecting the third party library to find the bug
you fork the repo, fix the bug and issue a pull request.
You have a warm fuzzy open source feeling but your
app is still broken until the maintainer merges your fix
How do I use my fix before it is merged upstream?

12. Overriding a package with an inline alias
See: https://getcomposer.org/doc/articles/aliases.md
//composer.json
"require": {
"simplethings/entity-audit-bundle": "dev-m2m-audit as dev-master",
//...
},
"repositories": [
{
"type": "vcs",
"url": "https://github.com/tommygnr/EntityAudit"
}
],

13. ToranProxy
• Created by Jordi Boggiano
• Acts as a proxy & cache for packagist and
github
• Helps support ongoing development of
composer
• https://toranproxy.com/

14. Questions
?