Function on_lsps_lsps2_invoice

plugins/lsps-plugin/src/client.rs:303–508

RPC Method handler for `lsps-jitchannel`. Calls lsps2.get_info, selects parameters, calculates fee, calls lsps2.buy, creates invoice.

(
    p: cln_plugin::Plugin<State>,
    v: serde_json::Value,
)

/// Calls lsps2.get_info, selects parameters, calculates fee, calls lsps2.buy,
/// creates invoice.
async fn on_lsps_lsps2_invoice(
    p: cln_plugin::Plugin<State>,
    v: serde_json::Value,
) -> Result<serde_json::Value, anyhow::Error> {
    #[derive(Deserialize)]
    struct Request {
        lsp_id: String,
        // Optional: for discounts/API keys
        token: Option<String>,
        // Pass-through of cln invoice rpc params
        pub amount_msat: cln_rpc::primitives::AmountOrAny,
        pub description: String,
        pub label: String,
    }

    let req: Request = serde_json::from_value(v).context("Failed to parse request JSON")?;
    debug!(
        "Handling lsps-buy-jit-channel request for peer {} with payment_size {:?} and token {:?}",
        req.lsp_id, req.amount_msat, req.token
    );

    let dir = p.configuration().lightning_dir;
    let rpc_path = Path::new(&dir).join(&p.configuration().rpc_file);
    let mut cln_client = cln_rpc::ClnRpc::new(rpc_path.clone()).await?;

    // 1. Get LSP's opening fee menu.
    let info_res: Lsps2GetInfoResponse = cln_client
        .call_raw(
            "lsps-lsps2-getinfo",
            &ClnRpcLsps2GetinfoRequest {
                lsp_id: req.lsp_id.clone(),
                token: req.token,
            },
        )
        .await?;

    // 2. Select Fee Parameters.
    // Simple strategy for now: choose the first valid option as LSPS2 requires
    // this to be the cheapest. Could be more sophisticated (e.g., user choice).
    let selected_params = info_res
        .opening_fee_params_menu
        .iter()
        .find(|params| {
            // Basic validation on client side: check expiry and promise length
            let fut_now = Utc::now() + Duration::minutes(1); // Add some extra time for network delay
            let expiry_valid = params.valid_until > fut_now;
            if !expiry_valid {
                warn!("Ignoring expired fee params from LSP {:?}", params);
            }
            expiry_valid
        })
        .cloned() // Clone the selected params
        .ok_or_else(|| {
            anyhow!(
                "No valid/unexpired fee parameters offered by LSP {}",
                req.lsp_id
            )
        })?;