VariableSerialization.config Custom Config file

Question

Hope you all are well. I am new in Sitecore. So,I have few queries to clear my doubts. I have shared a picture which is a part of config file.

1. In the picture why we used xmlns:role and xmlns:env ?
2. Inside the role:require attribute can I set any random text like demo/test or I need to set the predefined text like Standalone or ContentManagement ?
3. Inside the env:require attribute I can see there are two value set for two different parts. What is the meaning of env:require="user" and env:require="dev or qa or prod" ?

Answer 1

1. role and env is used in order to allow a rule-based configuration. This allow you to set configuration specific for given role or for given environment without a need to deploying different files to every separate Sitecore role or environment.

Full documentation can be found here: https://doc.sitecore.com/xp/en/developers/103/platform-administration-and-architecture/use-a-rule-based-configuration.html

2. For the role:require attribute you should use one (or more) of Sitecore roles which are:

• ContentDelivery
• ContentManagement
• Processing
• Reporting
• Standalone

In theory the setting will allow any other texts but I cannot think of any real live use case when you may need it.

More about roles can be found here: https://doc.sitecore.com/xp/en/developers/103/platform-administration-and-architecture/define-the-server-role.html

3. Those 2 setting means that if in web:config there will be setting:

sourceFolder variable will be set to D:\project\src. And if there will be any of dev, qa or prod in web.config, value of the variable will be set to /App_Data/unicorn.

More to be read here: https://doc.sitecore.com/xp/en/developers/103/platform-administration-and-architecture/add-a-custom-rule-to-your-configuration.html