Struct Base64String 

pub struct Base64String(/* private fields */);

Validated, URL-safe base64 string wrapper for secret data (no padding).

This struct ensures the contained string is valid URL-safe base64. Provides methods for decoding back to bytes.

Examples

let valid = Base64String::new("SGVsbG8".to_string()).unwrap();
assert_eq!(valid.expose_secret(), "SGVsbG8");
let bytes = valid.decode_into_bytes(); // Vec<u8> of "Hello"

Implementations

impl Base64String

pub fn new(s: String) -> Result<Self, &'static str>

Create a new Base64String from a String, validating it as URL-safe base64 (no padding).

The input String is consumed.

Security Note

Invalid inputs are only securely zeroized if the zeroize feature is enabled. Without zeroize, rejected bytes may remain in memory until the String is dropped normally. Enable the zeroize feature for secure wiping of invalid inputs.

Validation rules:

• Valid URL-safe base64 characters (A-Z, a-z, 0-9, -, _)
• No padding (‘=’ not allowed, as we use no-pad)
• Must be decodable as valid base64 (prevents to_bytes() panics)

Errors

Returns Err("invalid base64 string") if validation fails.

Example

use secure_gate::{encoding::base64::Base64String, ExposeSecret};
let valid = Base64String::new("SGVsbG8".to_string()).unwrap();
assert_eq!(valid.expose_secret(), "SGVsbG8");
let bytes = valid.decode_into_bytes(); // Vec<u8> of "Hello"

pub fn byte_len(&self) -> usize

Exact number of bytes the decoded base64 string represents.

pub fn decode_to_bytes(&self) -> Vec<u8>

decode_to_bytes: borrowing, allocates fresh Vec<u8> from decoded bytes

pub fn decode_into_bytes(self) -> Vec<u8>

decode_into_bytes: consuming, decodes then zeroizes the wrapper immediately

Trait Implementations

impl Debug for Base64String

Debug implementation (always redacted).

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl ExposeSecret for Base64String

Available on crate feature encoding-base64 only.

Implementation for Base64String - read-only access.

Encoding wrappers only provide read-only access to prevent invalidation of validation invariants. The Inner type is str since encoded strings are always valid UTF-8.

type Inner = str

The inner secret type being exposed.

fn expose_secret(&self) -> &str

Expose the secret for read-only access.

fn len(&self) -> usize

Returns the length of the secret.

fn is_empty(&self) -> bool

Returns true if the secret is empty.

impl PartialEq for Base64String

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for Base64String