turnkey_api_key_stamper 0.5.0

# turnkey_api_key_stamper

This crate contains structs and utilities to work with P-256 keys, which [Turnkey](https://docs.turnkey.com/) uses as a primary way of authentication.

## Creating a new P-256 API key

```rust
use turnkey_api_key_stamper::TurnkeyP256ApiKey;

let api_key = TurnkeyP256ApiKey::generate();
```

## Loading API keys from env

If you keep API keys in env vars, load it with `from_bytes` or `from_strings`:

```rust,no_run
use std::env;
use turnkey_api_key_stamper::TurnkeyP256ApiKey;

// Assuming the env var is a hex-encoded string
let api_private_key = env::var("TURNKEY_API_PRIVATE_KEY").expect("cannot load TURNKEY_API_PRIVATE_KEY");
let api_key = TurnkeyP256ApiKey::from_strings(api_private_key, None).expect("loading API key failed");
```

If you want to store API keys in `.env` files, use [`dotenvy`](https://docs.rs/dotenvy/latest/dotenvy/).

## Load API keys from files

If you have generated API keys with Turnkey's [command-line tool](https://github.com/tkhq/tkcli) you can load them with:

```rust
use turnkey_api_key_stamper::TurnkeyP256ApiKey;

let api_key = TurnkeyP256ApiKey::from_files(
    "/home/user/.config/turnkey/keys/key.priv",
    Some("/home/user/.config/turnkey/keys/key.pub"
).expect("loading should succeed"));
```

## Creating an API stamp to sign Turnkey requests

The API is straightforward, once you have a handle on an API key, call `stamp`:

```rust
use turnkey_api_key_stamper::{TurnkeyP256ApiKey, Stamp};

let api_key = TurnkeyP256ApiKey::generate();
let stamp = api_key.stamp("POST request body goes here".as_bytes());
```

The stamp produced is a base64-encoded value, ready to be used as a stamp header. See [our documentation](https://docs.turnkey.com/developer-reference/api-overview/stamps#api-keys) for more information.

## Error handling

Errors are centralized in `StamperError`.