Broadcast transactions

[rustaceanrob]

There is no transaction sharing logic within node. For the sending half of the wallet POC, a generalized broadcast queue has to be implemented.

[yancyribbens]

Do you have an idea or framework in mind for implementing the send half?

[rustaceanrob]

Sure, on a high level I think we will want to do something like a not-so-private broadcast. When a transaction needs to be sent, we:

1. spin up a connection to a new peer,
2. share the transaction, and
3. wait for it to be advertised back by our current connection.

For an initial go at it, we can also omit 3.

For those that are less familiar, transactions are shared with a wtxid, then we wait for the peer to respond with getdata, then send the transaction. However, technically it is also possible to just send the transaction unsolicited.

This becomes more interesting with one-parent-one-child package relay but I will leave that as a follow up/feature request.

How this looks in Rust code I am agnostic to.

[yancyribbens]

What about transaction building? I thought that was part of the mentioned send half of wallet construction.

[rustaceanrob]

That would fall under #55, which is also up for grabs. I don't have a strong opinion, but the BDK team has been putting a lot of time into bdk-tx so it is worth checking out.

[yancyribbens]

BDK team has been putting a lot of time into bdk-tx so it is worth checking out.

I was thinking of assembling something that uses the coin-selection lib I wrote. That's one of the reasons I've started working on the P2P layer and following projects like this. Although, I'm not sure that goal is very compatible with using BDK.

[rustaceanrob]

#66 confirms this works