ENV variable access on Heroku with Apache - php

Question

I have a PHP/Apache application deployed to Heroku. I want to enable basic auth on this when running on Heroku. This worked well...
AuthUserFile /app/prototypes/.htpasswd
AuthType Basic
AuthName "Restricted Access"
Require valid-user
However, I want to only enable this if PASSWORD_PROTECTED is set. I set a heroku config var like so:
heroku config:set PASSWORD_PROTECTED=true
and then updated .htaccess to look like:
<IfDefine %{ENV:PASSWORD_PROTECTED}>
AuthUserFile /app/prototypes/.htpasswd
AuthType Basic
AuthName "Restricted Access"
Require valid-user
</IfDefine>
But the Require valid-user never gets run, so I don't seem to be able to access ENV vars from .htacess in Heroku or I am doing this wrong. Any thoughts on how to do this properly?

Answer 1

You're on the right track, but your syntax is a little off.
Rather than <IfDefine>, which lets you test for variables set with Define or via the -D parameter on startup, you should use the <If> directive. This was new in Apache 2.4, so examples are a little thin on the ground, but we can use those examples along with this rather technical expression reference to come up with this:
<If "-T reqenv('PASSWORD_PROTECTED')">
AuthUserFile /app/prototypes/.htpasswd
AuthType Basic
AuthName "Restricted Access"
Require valid-user
</If>
reqenv is a function that looks up an environment variable; -T is an operator that returns true unless its argument is empty, 0, "false", "off", or "no".