added ability to add route hints to createInvoice/createHoldInvoice

[SeverinAlexB]

Do you have a time eta to get this merged?

[alexbosworth]

Oh I didn't see this, does it actually work? I think it won't do anything

[SeverinAlexB]

Works like a charm.

{
      chain_address: undefined,
      created_at: '2023-07-27T02:23:42.000Z',
      description: 'test jit',
      id: 'a5c3aa5b569b651612456805bb13f7752c25ebef169380133a787a88eb40a0f2',
      mtokens: '100000000',
      payment: '325cd0bc2fc37bfd855889ecdf1005405e148f3b67ff1b28257c4d1511027eac',
      request: 'lnbcrt1m1pjvr4fwpp55hp65k6kndj3vyj9dqzmkylhw5kzt6l0z6fcqye60pag366q5reqdqdw3jhxapqdf5hgcqzzsxqrpcgrzjqfl3vv6xpnr9gxk9d6uw6dvmmcsaq3crp3t4ktvxmsky9r2nl6gmwqqqqyqqqqgqqyqqqqqqqqqqqqqq9qsp5xfwdp0p0cdalmp2c38kd7yq9gp0pfremvll3k2p903x32ygz06kq9qyyssqeppevvey7sr6kuwfnxld7r9c2ucxumxzsr6en0vu7hwgw6g5txxh9fl27kkdsnver9hg2lwxn7ee0uyjzlaradgg4kwtcz22aftpywcph7gstu',
      secret: '7ceac91141b61e1e620d44d531b63f86abc088d06e5e488fe81a7e1876200a26',
      tokens: 100000
    }

Decoded: https://lightningdecoder.com/lnbcrt1m1pjvr4fwpp55hp65k6kndj3vyj9dqzmkylhw5kzt6l0z6fcqye60pag366q5reqdqdw3jhxapqdf5hgcqzzsxqrpcgrzjqfl3vv6xpnr9gxk9d6uw6dvmmcsaq3crp3t4ktvxmsky9r2nl6gmwqqqqyqqqqgqqyqqqqqqqqqqqqqq9qsp5xfwdp0p0cdalmp2c38kd7yq9gp0pfremvll3k2p903x32ygz06kq9qyyssqeppevvey7sr6kuwfnxld7r9c2ucxumxzsr6en0vu7hwgw6g5txxh9fl27kkdsnver9hg2lwxn7ee0uyjzlaradgg4kwtcz22aftpywcph7gstu

[alexbosworth]

ah interesting, i'll have to make a regtest setup to try it out

[alexbosworth]

i've been doing it a different way, like this: https://github.com/alexbosworth/balanceofsatoshis/blob/master/offchain/create_invoice.js

[SeverinAlexB]

So if I understand correctly, the user indicates if they want to add private channel hints with is_hinting and then you add all private channels in there?

[alexbosworth]

It allows for selecting individual hints too

[alexbosworth]

I didn't notice that this was added to LND though so it should be added yeah

The changes on the code side i'm thinking about is to make the input of route hints match the output of route hints on decodePaymentRequest because the formatting is a bit different, and also more comments documenting that and also I need to figure out when this was added to LND exactly

[SeverinAlexB]

It allows for selecting individual hints too

Can you point me to the code line? Can't find it.

The changes on the code side i'm thinking about is to make the input of route hints match the output of route hints on decodePaymentRequest because the formatting is a bit different, and also more comments documenting that and also I need to figure out when this was added to LND exactly

That sounds reasonable. Do you want to do that or shall I?

[alexbosworth]

you could edit it, i think i have some code for that translation somewhere but i can't find it

how I do it actually is I pass channel policies around, then compute the hop hints from those: https://github.com/alexbosworth/balanceofsatoshis/blob/master/offchain/sign_payment_request.js#L123

maybe passing channel policies like done above would even be easier or an alternative approach in order to not make the caller do any translation?

[alexbosworth]

i think this would convert the decodepaymentrequest type hints back to the rpc type hints:

const {chanNumber} = require('bolt07');

const routeHints = args.routes.map(route => {
  const path = route.map((hop, i) => {
    if (!i) {
      return;
    }

    return {
      node_id: route[i - [hop].length].public_key,
      chan_id: chanNumber({channel: hop.channel}).number,
      fee_base_msat: hop.base_fee_mtokens,
      fee_proportional_millionths: hop.fee_rate,
      cltv_expiry_delta: hop.cltv_delta,
    };
  });

  return {hop_hints: path.filter(n => !!n)};
});

[alexbosworth]

oh actually i found where a mapper already exists in the codebase: https://github.com/alexbosworth/lightning/blob/master/lnd_requests/route_hint_from_route.js

[alexbosworth]

I merged the combo of that method with invoice, but I had to remove the types since this now shares the decode payment request hints type - could be another PR? ping @bkiac

[SeverinAlexB]

Thx. Sorry, was busy the recent days

[bkiac]

I merged the combo of that method with invoice, but I had to remove the types since this now shares the decode payment request hints type - could be another PR? ping @bkiac

opened a PR with the types #143