Filtering Reference

This section reference all Rhai functions used through the rule engine and vSMTP configuration. Those functions are split by modules.

They list:

• All standard functions available for email filtering. (referred by the fn keyword)
• Operators. (referred by the op keyword)
• Objects getters. (referred by the get keyword)
• Objects setters. (referred by the set keyword)

Documentation

Documentation for each function is written using markdown, and is split between sections (tabs):

Section	Description
Args	Arguments to pass to the function.
Return	Value that the function returns.
SMTP Stages	SMTP stages where this function can be called from.
Note	Additional comments for the function.
Examples	Code examples using the function.
Errors	Errors that can happen during the execution of the function.

Errors

A function that is marked with the Errors section can fail. (It can throw a Rhai exception)

Exceptions stops the evaluation of the rule engine and return a deny code. To handle exceptions, you can use the try catch statement in Rhai.

Dynamic objects

Rhai uses the concept of dynamic objects, which means that some functions can take any parameter types or return anything.

A function with a dynamic parameter and dynamic return value

fn my_function(arg1: ?) -> ? {
    return arg1;
}

As you can see, dynamic values are marked with the ? symbol in the documentation. This means that my_function can be passed any type of parameter, and will return any object type.

calling my_function with mutliple parameters types

my_function("hello, world!"); // using a string, returns the "hello, world!" string.
my_function(42);              // using a number, returns the 42 number.
// ...

Checkout the Rhai Dynamic reference for more details.

Example

Here is an example of how a function will be rendered in the documentation.

fn my_function

fn hello_world(name: String) -> String

Description

This is the description section of the hello_world function.

This function returns a "hello world!" string with the name passed as parameter.

Args

• name - The name to display next to the "hello world" string.

Return

• String - A "hello world!" string.

SMTP stages

All of them!

Example

let hello_world = hello_world("John"); // Returns "Hello World, John!".