Sitecore use global and environment variables in config files

The Sitecore config files are a complex machine and it requires a healthy mind to work with it. Fortunately Sitecore have implemented a few tricks to ease our pain. This article focuses on 2 parts: global variable replacement and environment variable replacement.

GLOBAL VARIABLES:

Global variables are defined once and can then be reused in all your config settings.

Maybe you have seen these variables:

<sitecore>
  <sc.variable name="dataFolder" value="/App_Data" />
  <sc.variable name="mediaFolder" value="/upload" />
  <sc.variable name="tempFolder" value="/temp" />
</sitecore>

The sc.variable element defines the variable. The variables can then be used where you need them by writing $(variable_name):

<file value="$(dataFolder)/logs/myfile.log"/>
<setting name="IndexFolder" value="$(dataFolder)/indexes" />

The above variables are just the built in ones. You can create your own variables and use them too.

ENVIRONMENT VARIABLES:

Since Sitecore 8.2 we have been blessed with environment variable replacements too.

Let’s say you have an environment variable on your machine:

Global Environment Variables

You can add the environment variable to the config by writing $(env:variable_name):

<setting name="Environment" value="$(env:ASPNETCORE_ENVIRONMENT)" />

This is especially nifty as you can deploy the same config file to different environments and control your application per server.

MORE TO READ:

• Environment variables in Sitecore configs by Søren Kruse
• How to replace variables with values from connectionstrings or applicationsettings in sitecore config files by Bartłomiej Mucha