LIGHTNING-PAY(7) ================ :doctype: manpage NAME ---- lightning-pay - Protocol for sending a payment to a BOLT11 invoice SYNOPSIS -------- *pay* 'bolt11' ['msatoshi'] ['description'] ['riskfactor'] ['maxfeepercent'] DESCRIPTION ----------- The *pay* RPC command attempts to find a route to the given destination, and send the funds it asks for. If the 'bolt11' does not contain an amount, 'msatoshi' is required, otherwise if it is specified it must be 'null'. If 'bolt11' contains a description hash ('h' field) 'description' is required, otherwise it is unused. The 'riskfactor' is described in detail in lightning-getroute(7), and defaults to 1.0. The 'maxfeepercent' limits the money paid in fees, and defaults to 0.5. The `maxfeepercent' is a percentage of the amount that is to be paid. The *pay* RPC command will randomize routes slightly, as long as the route achieves the targeted 'maxfeepercent'. The response will occur when the payment fails or succeeds. Once a payment has succeeded, calls to *pay* with the same 'bolt11' will succeed immediately. When using 'lightning-cli', you may skip optional parameters by using 'null'. Alternatively, use *-k* option to provide parameters by name. RETURN VALUE ------------ On success, this returns the payment 'preimage' which hashes to the 'payment_hash' to prove that the payment was successful. It will also return, a 'getroute_tries' and a 'sendpay_tries' statistics for the number of times it internally called *getroute* and *sendpay*. On error, if the error occurred from a node other than the final destination, the route table will be updated so that getroute(7) should return an alternate route (if any). An error from the final destination implies the payment should not be retried. The following error codes may occur: * -1. Catchall nonspecific error. * 200. A previous *sendpay* or *pay* is in progress. * 201. Already paid with this 'hash' using different amount or destination. * 203. Permanent failure at destination. The 'data' field of the error will be routing failure object. * 205. Unable to find a route. * 206. Route too expensive. The 'data' field of the error will indicate the actual 'fee' as well as the 'feepercent' percentage that the fee has of the destination payment amount. * 207. Invoice expired. Payment took too long before expiration, or already expired at the time you initiated payment. The 'data' field of the error indicates 'now' (the current time) and 'expiry' (the invoice expiration) as UNIX epoch time in seconds. Error codes 202 and 204 will only get reported at *sendpay*; in *pay* we will keep retrying if we would have gotten those errors. A routing failure object has the fields below: * 'erring_index'. The index of the node along the route that reported the error. 0 for the local node, 1 for the first hop, and so on. * 'erring_node'. The hex string of the pubkey id of the node that reported the error. * 'erring_channel'. The short channel ID of the channel that has the error, or '0:0:0' if the destination node raised the error. * 'failcode'. The failure code, as per BOLT #4. * 'channel_update'. The hex string of the 'channel_update' message received from the remote node. Only present if error is from the remote node and the 'failcode' has the UPDATE bit set, as per BOLT #4. AUTHOR ------ Rusty Russell is mainly responsible. SEE ALSO -------- lightning-listpayments(7), lightning-decodepay(7), lightning-listinvoice(7), lightning-delinvoice(7), lightning-getroute(7), lightning-invoice(7). RESOURCES --------- Main web site: https://github.com/ElementsProject/lightning