Two days ago, I had to switch projects at work and go work on a different project. As with a new project, setting up the project on my dev machine was the first thing I needed to do. I decided to setup the project with Docker for obvious reasons; on-boarding future engineers to the project will be a breeze.

While setting up the project, I realised that Docker —env and PHP-FPM don’t quite mix properly. While passing in an environment variable file when running the containers will work, getting those environment variables with PHP’s getenv becomes an issue. The solution to this is to add the environment variables into the config file of PHP-FPM located at etc/php5/fpm/pool.d/www.conf.

Environment variables in the PHP-FPM config file follow a regular pattern, every variable begins with the word env followed by brackets for the actual variable name and a value e.g. env[DB_HOST] = 127.0.0.1. Another thing you want to watch out for when setting up variables and values are the use of reserve words and special characters. Words like yes,null, etc, shouldn’t be used in variables and also special characters like ! should be avoided.

Note: There are reserved words which must not be used as keys for ini files. These include: null, yes, no, true, false, on, off, none. Values null, off, no and false result in “”, and values on, yes and true result in “1”, unless INI_SCANNER_TYPED mode is used (as of PHP 5.6.1). Characters ?{}

&~!()^” must not be used anywhere in the key and have a special meaning in the value.

Why am I talking about this?

I spent almost an entire trying to debug my variables and just didn’t know why PHP-FPM was failing each time I ran a syntax check test for the configuration file — php-fpm -t. It turns out, one of the variable value had an exclamation sign (!), which made PHP-FPM really unhappy.

PHP:  syntax error, unexpected '!' in Unknown on line 1
[16-Jul-2016 05:24:41] ERROR: Unable to include /etc/php5/fpm/pool.d/www.conf from /etc/php5/fpm/php-fpm.conf at line 404
[16-Jul-2016 05:24:41] ERROR: failed to load configuration file '/etc/php5/fpm/php-fpm.conf'
[16-Jul-2016 05:24:41] ERROR: FPM initialization failed

I hope this helps someone and save you from the trouble I had to deal with.

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Do you want to say hello? Email me - celestineomin@gmail.com

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