sorocharge-mpp

MPP’s draft-stellar-charge-00, the "stellar" payment method for the "charge" intent. Wire shapes are copied verbatim from tempoxyz/mpp-specs (draft-stellar-charge-00, draft-payment-intent-charge-00, draft-httpauth-payment-01).

Client

#![allow(unused)]
fn main() {
impl<'a> MppClient<'a> {
    pub fn new(
        rpc: &'a stellar_rpc_client::Client,
        request_timeout: std::time::Duration,
    ) -> Result<Self, MppError>;

    pub async fn get_with_payment(
        &self,
        url: &str,
        signer: &dyn sorocharge_signer::Signer,
        network_passphrase: &str,
    ) -> Result<reqwest::Response, MppError>;
}
}

See Paying with MPP.

Server

#![allow(unused)]
fn main() {
impl<'a> MppServer<'a> {
    pub fn new(
        rpc: &'a stellar_rpc_client::Client,
        signer: &'a dyn sorocharge_signer::Signer,
        network_passphrase: String,
        config: MppServerConfig,
    ) -> Self;

    pub fn build_challenge_header(
        &self,
        id: &str,
        realm: &str,
        request: &ChargeRequest,
        expires: chrono::DateTime<chrono::Utc>,
    ) -> Result<String, MppError>;

    pub async fn settle_credential(
        &self,
        credential: &Credential,
        expected: &ChargeRequest,
        current_time: chrono::DateTime<chrono::Utc>,
        already_consumed: bool,
    ) -> Result<Receipt, MppError>;
}
}

#![allow(unused)]
fn main() {
pub struct MppServerConfig {
    pub max_transaction_fee_stroops: i64,  // default 50_000 — not spec-mandated, this
                                            // crate's own conservative choice
    pub inclusion_buffer_stroops: i64,     // default 100
}
}

See Running an MPP server for what settle_credential deliberately doesn’t own (challenge storage, replay protection) and why.

Wire types

#![allow(unused)]
fn main() {
pub struct MethodDetails {
    pub network: String,   // "stellar:pubnet" | "stellar:testnet"
    pub fee_payer: bool,   // default false
}

pub struct ChargeRequest {
    pub amount: String,                  // decimal string, base units
    pub currency: String,                // SEP-41 SAC contract (C...)
    pub recipient: String,               // account (G...)
    pub description: Option<String>,
    pub external_id: Option<String>,
    pub method_details: MethodDetails,
}

pub struct Challenge {
    pub id: String,
    pub realm: String,
    pub method: String,                  // "stellar"
    pub intent: String,                  // "charge"
    pub request: String,                 // base64url-encoded ChargeRequest, still encoded
    pub description: Option<String>,
    pub opaque: Option<String>,
    pub digest: Option<String>,
    pub expires: Option<String>,         // RFC 3339
    pub header: Option<String>,          // "Payment-Authorization" if the challenge selected it
}

pub enum Payload {
    Transaction { transaction: String },  // base64 TransactionEnvelope — pull mode
    Hash { hash: String },                // 64-char hex tx hash — push mode
}

pub struct Credential {
    pub challenge: Challenge,
    pub payload: Payload,
    pub source: Option<String>,          // e.g. "did:pkh:stellar:testnet:G..."
}

pub struct Receipt {
    pub method: String,                  // "stellar"
    pub reference: String,               // settled tx hash
    pub status: String,                  // "success"
    pub timestamp: String,               // RFC 3339
    pub external_id: Option<String>,
}
}

Headers

MppError