mpp-test-sdk (Rust)

Rust SDK for the Machine Payments Protocol (MPP) — HTTP 402 payment flow on Solana.

No external Solana wallet libraries needed. Pure Rust: ed25519 signing, base58, and JSON-RPC over standard async HTTP.

[dependencies]
mpp-test-sdk = "1.0"
tokio = { version = "1", features = ["full"] }

---

Client

use mpp_test_sdk::{create_test_client, TestClientConfig};

#[tokio::main]
async fn main() {
    // Zero config — generates wallet, airdrops 2 SOL on devnet
    let client = create_test_client(TestClientConfig::default()).await.unwrap();
    println!("Wallet: {}", client.address);

    let resp = client.fetch("http://localhost:3001/api/data", None).await.unwrap();
    println!("Status: {}", resp.status());
}

Mainnet

use mpp_test_sdk::{create_test_client, SolanaNetwork, TestClientConfig};

let client = create_test_client(TestClientConfig {
    network: Some(SolanaNetwork::Mainnet),
    secret_key: Some(my_keypair_bytes), // 32-byte seed or 64-byte keypair
    ..Default::default()
})
.await
.unwrap();

Lifecycle callbacks

use mpp_test_sdk::{create_test_client, TestClientConfig};

let client = create_test_client(TestClientConfig {
    on_step: Some(Box::new(|step| println!("[{:?}] {}", step.step_type, step.message))),
    ..Default::default()
})
.await
.unwrap();

Shared client (drop-in fetch)

use mpp_test_sdk::mpp_fetch;

let resp = mpp_fetch("http://localhost:3001/api/data", None).await.unwrap();

---

Server

MppServer::charge is framework-agnostic — pass the raw payment-receipt header value and act on the result.

use mpp_test_sdk::{create_test_server, ChargeOptions, ChargeResult, TestServerConfig};

let server = create_test_server(TestServerConfig::default()).unwrap();

// Inside your request handler:
let receipt = request.headers().get("payment-receipt").and_then(|v| v.to_str().ok());
match server.charge(receipt, &ChargeOptions { amount: "0.001" }).await {
    ChargeResult::NeedsPayment { payment_request_header, body } => {
        // respond 402, set Payment-Request header
    }
    ChargeResult::Authorized => {
        // serve the response
    }
    ChargeResult::Denied(reason) => {
        // respond 403
    }
}

---

Error types

Type	When thrown
Error::Faucet(MppFaucetError)	Devnet/testnet airdrop failed after 3 retries
Error::Payment(MppPaymentError)	HTTP error or malformed Payment-Request
Error::Timeout(MppTimeoutError)	Full flow exceeded timeout (default 30 s)
Error::Network(MppNetworkError)	Mainnet used without secret_key

---

Networks

Constant	RPC	Airdrop
SolanaNetwork::Devnet	api.devnet.solana.com	✓
SolanaNetwork::Testnet	api.testnet.solana.com	✓
SolanaNetwork::Mainnet	api.mainnet-beta.solana.com	—

---

Related

• mpptestkit.com — interactive playground
• npm: mpp-test-sdk — TypeScript SDK
• PyPI: mpp-test-sdk — Python SDK
• GitHub: sdk-go — Go SDK
• GitHub: sdk-rust — this SDK