pub fn validate_base64_urlsafe(s: &str) -> Result<(), ValidationError>Expand description
Validate that s is a well-formed URL-safe base64 string:
characters from [A-Za-z0-9_-], length a multiple of 4 after
optional = padding (or, by RFC 4648 convention, padding may
be omitted in URL-safe encoding — we accept either).
§Errors
ValidationError { code: "invalid_base64", ... }.