coult 0.3.0

# Coult

A simple, async Vault client in Rust using **Hyper v1**, **hyper-rustls**, and **Tokio** for secure communication with HashiCorp Vault.

## Features

- Supports Vault HTTP API v1 (health check, secrets retrieval)
- Compatible with Vault secret engines v1 and v2
- TLS support with `hyper-rustls` and WebPKI roots
- Async and efficient using `hyper-util` and `tokio`
- Customizable Vault connection options (address, port, token, protocol)
- Error handling with detailed Vault status codes


## Usage

```rust
use coult::{Config, Vault};
use serde::Deserialize;
#[derive(Debug, Deserialize)]
struct Secret {
    password: String,
}

#[tokio::main]
async fn main() {
    tracing_subscriber::fmt::init();
    let vault = Vault::new()
        .address("localhost")
        .protocol("http")
        .token("imtokenbro")
        .port(8200)
        .secret_path("kv/data/test")
        .build().await.unwrap();
    let data = vault.get_secret::<Secret>().await.unwrap();
    println!("{:?}", data)
}

```

Replace YourSecretStruct with your custom struct that implements serde::Deserialize.

## API

### VaultBuilder
- address(String): Set Vault server address (default: 127.0.0.1)
- port(u16): Set Vault server port (default: 8200)
- token(String): Set Vault token for authentication
- secret_path(String): Set the Vault secret path to retrieve
- https(): Use HTTPS protocol (default: http)
- protocol(String): Set protocol (http or https)
- build(): Build and return a Vault instance asynchronously

### Vault
- health_check(): Check Vault health status
- get_secret<T>(): Get secret from Vault using secret engine v1
- get_secret_v2<T>(): Get secret from Vault using secret engine v2

### Error Handling
The client returns detailed errors based on Vault HTTP status codes, such as:

- VaultSealed (503)
- VaultInvalidPath (404)
- VaultNotInitialized (501)
- VaultActiveDRsecondaryNode (472)
- VaultStandbyPerformanceNode (473)
- Other Vault-specific errors

### Environment Variables

If values are not explicitly set in the builder, these environment variables will be used as defaults:

- **VAULT_ADDRESS** - Vault server address
- **VAULT_PORT** - Vault server port
- **VAULT_TOKEN** - Vault authentication token
- **VAULT_SECRET_PATH** - Vault secret path
- **VAULT_PROTOCOL** - Protocol (http or https)

## Contributing
Contributions are welcome! Please open issues or submit pull requests.