Struct SecureString 

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

A secure string that automatically zeros its memory on drop.

This type should be used for any sensitive data like API keys, tokens, or passwords to prevent potential memory disclosure through:

• Core dumps
• Swap files
• Memory scanning tools
• Debuggers

Security

The contained data is automatically zeroed when the value is dropped, using the zeroize crate which provides compiler-fence-backed guarantees that the zeroing operation won’t be optimized away.

Design: Why No Deref<Target=str>?

This type intentionally does NOT implement Deref to maintain security:

• Explicit access: Requires .as_ref() call, making code auditable
• Prevents silent leakage: No implicit coercion to &str in logs/errors
• Grep-able security: Easy to audit with git grep "\.as_ref\(\)"
• Industry standard: Aligns with secrecy crate’s proven approach

The slight ergonomic cost of typing .as_ref() is a worthwhile security trade-off that prevents accidental secret exposure.

Example

use api_keys_simplified::SecureString;

let sensitive = SecureString::from("my_secret_api_key");

// Explicit access (good - auditable)
let key = sensitive.as_ref();

// Debug output is automatically redacted (safe)
println!("{:?}", sensitive);  // Output: "SecureString([REDACTED])"

// Memory is automatically zeroed when sensitive goes out of scope

Implementations

impl SecureString

pub fn new(s: String) -> Self

Creates a new SecureString from a String.

The original string is moved and will be zeroed when this SecureString is dropped.

pub fn len(&self) -> usize

Returns the length of the string in bytes.

pub fn is_empty(&self) -> bool

Returns true if the string is empty.

Trait Implementations

impl AsRef<str> for SecureString

fn as_ref(&self) -> &str

Converts this type into a shared reference of the (usually inferred) input type.

impl Clone for SecureString

fn clone(&self) -> SecureString

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SecureString

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

Formats the value using the given formatter.

impl Display for SecureString

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

Formats the value using the given formatter.

impl Drop for SecureString

fn drop(&mut self)

Executes the destructor for this type.

impl From<&str> for SecureString

fn from(s: &str) -> Self

Converts to this type from the input type.

impl From<String> for SecureString

fn from(s: String) -> Self

Converts to this type from the input type.

impl Zeroize for SecureString

fn zeroize(&mut self)

Zero out this object from memory using Rust intrinsics which ensure the zeroization operation is not “optimized away” by the compiler.