📄️ Overview
Expressions in Stalwart Mail Server allow administrators to define complex, dynamic criteria for evaluating and handling email messages based on various attributes of the emails themselves and contextual variables such as IP address, sender, recipient and more. These expressions enable fine-grained control over mail routing, filtering, and processing rules, making them a powerful tool for customizing mail server behavior. Expressions can be applied to most parameters of the configuration file and and also used from Sieve scripts.
📄️ Operators
The following logical, arithmetic and comparison operators can be used within an expression:
📄️ Functions
Functions are integral components of expressions in Stalwart Mail Server. They perform specific operations on one or more operands (parameters) and are used to construct dynamic and powerful expressions for evaluating conditions and generating dynamic values. Functions can vary in the number of parameters they require, from zero to multiple, and each has a distinct purpose in processing and decision-making logic.
📄️ Values
Dynamic Values are an integral part of configuration that allows for more sophisticated and adaptable setups. Through dynamic values, Stalwart Mail Server provides administrators with a high degree of flexibility, allowing them to create configurations that adapt in real-time to the context of the server operation.