You can parse an .env file as an .ini with PHP - but there's a catch

The humble .env file is a useful and low-tech way of storing persistent environment variables. Drop the file on your server and let your PHP scripts consume it with glee.

But consume it how? There are lots of excellent parsing libraries for PHP. But isn't there a simpler way? Yes! You can use PHP's parse_ini_file() function and it works.

But…

.env and .ini have subtly different behaviour which might cause you to swear at your computer.

Let's take this example:

⧉ ENV# This is a comment
USERNAME="edent"

Run $env = parse_ini_file( ".env" ); and you'll get back an array setting the USERNAME to be "edent". Hurrah! Works perfectly. Ship it!

But consider this:

⧉ ENV# This is a comment
USERNAME="edent" # Don't use an @ symbol here.

It will happily tell you that the username is "edent# Don"

WTAF?

Here's the thing. The comment character for .ini is not # - it's the semicolon ;

Let me give you some other examples of things which will fuck up your parsing:

⧉ ENV# Documentation at https:/example.com/?doc=123
DOCUMENTATION=123
# Set the password
PASSWORD=qwerty;789

That gets us back this PHP array:

⧉ PHP[
  '# Documentation at https:/example.com/?doc' => '123',
  'DOCUMENTATION' => '123',
  'PASSWORD' => 'qwerty',
];

When the .ini is parsed, it ignores every line which doesn't have an = sign. It also treats literal semicolons as the start of a new comment until they're wrapped in quotes.

My code highlighter should show you how it is parsed:

⧉ INI# Documentation at https:/example.com/?doc=123
DOCUMENTATION=123
# Set the password
PASSWORD=qwerty;789

It gets worse. Consider this:

⧉ ENV# Set the "official" name
REALNAME="Arthur, King of the Britons"

That immediately fails with PHP Warning: syntax error, unexpected '"' in envtest on line 1

You can use single quotes in pseudo-comments just fine, but if the ini parser sees a double quote without an equals then it throws a wobbly.

I'm sure there are several other gotchas as well. For example, there are certain reserved words and symbols you can't used as a key.

This will fail:

⧉ ENV# Can we fix it? Yes we can!
FIX=true

It chokes on the exclamation point.

How to solve it (the stupid way)

The comments on an .env file start with a hash.

The comments on an .ini file start with a semicolon.

So, it is perfectly valid for a hybrid file to have its comments start with #;

Look, if it's stupid but it works…

What Have We Learned Here Today?

• There's a right way and a wrong way to do .env parsing.
• The wrong way works, up until the point it doesn't.
• You should probably use a proper parser rather than hoping your .env looks enough like an .ini to pass muster.

On next week's show - why you shouldn't store your passwords inside a JPEG!