Configuration

Validators are instantiated with a default configuration. You can override some values to your needs by providing a Configuration when instantiating your validator, using Validator<T>(CONFIGURATION_INSTANCE) { ... }.

Here's an example where we override the default violation message and the root path:

val customConfig = Configuration {
    defaultViolationMessage = "The field contains an invalid value"
    rootPath("custom", "root", "path")
}

val validateString = Validator<String>(customConfig) {
    length.constrain { false }
}

when (val result = validateString("foo")) {
    is ValidationResult.Success -> {}

    is ValidationResult.Failure -> {
        for ((message, path) in result.violations) {
            println("$path: $message")
        }
    }
}

The output is the following:

[custom, root, path, length]: The field contains an invalid value

Without providing any custom configuration, it would have been:

[length]: The value is invalid.

Last modified: 19 December 2024