Custom Prompt Types

Defining a custom prompt type is a simple as just creating a new Prompt instance and configuring the parameters to match your requirements.

As a simple example we will do a super quick run through through of the built-in YesNoPrompt.

The Prompt itself is defined pretty simply:

func YesNoPrompt(message string, hint string, required Optionality, 
    defaultValue bool) Prompt

Prompt{
    Message:            message,
    ValueHint:          hint,
    DefaultValue:       defaultValue,
    Required:           required,
    RetryIfNoMatch:     true,
    FailIfNoMatch:      true,
    CaseSensitiveMatch: false,
    ValidationFunc: func(prompt *Prompt, value string) (string, Validity) {
        _, validity := isValidYesOrNoValue(value)
        return value, validity
    },
    ValueConverter: func(prompt *Prompt, value string) interface{} {
        return isPositiveStringValue(value, false)
    },
}

The display options (Message and Hint) and the DefaultValue are provided through the functional call, but the validation and conversion functions are designed to match the entered value to a collection of valid yes or no responses and in the end the value is converted to a bool value.

The other parameters are configured so that the matching and failure logic lines up with the appropriate user experience.

To dig deeper, take a look at the built-in Prompt configurations in the prompts.go file.