Nginx HTTP Server - Fourth Edition

Conditional structure

The following set of commands will allow you to include text or other directives, depending on a condition. The conditional structure can be established with the following syntax:

<!--# if expr="expression1" --> 
[...] 
<!--# elif expr="expression2" --> 
[...] 
<!--# else --> 
[...] 
<!--# endif --> 

The expression can be formulated in three different ways:

• Inspecting a variable: <!--# if expr="$variable" -->. Similar to the if block in the Rewrite module, the condition is true if the variable is not empty.
• Comparing two strings: <!--# if expr="$variable = hello" -->. The condition is true if the first string is equal to the second string. Use != instead of = to revert the condition (the condition is true if the first string ...