truenas/docs/schema/string.md

String Schema

Example of string schema options:

schema:
    type: string
    private: true
    min_length: 5
    max_length: 12
    valid_chars: "[a-zA-Z0-9]$"

Following attributes can be added to string schema to enforce validation when a chart release is being created/edited:

min_length is an integer field which adds validation to ensure value provided for this variable is at least the specified characters.

max_length is an integer field which adds validation to ensure value provided for this variable is at max the specified characters.

private is a boolean field which when set by chart maintainer, will result in the value of the variable not being shown to the user in the UI. This is useful for sensitive fields like password where a dummy character is placed for each character provided for this string in the UI.

valid_chars is a string field which chart maintainer can specify to provide a regex to enforce that the value provided for the variable should conform to a pattern. TrueNAS Scale will use python3 regex (https://docs.python.org/3/library/re.html) syntax to enforce valid_chars.