Add assumevalid option for channel announcements

[ariard]

Right now, we ask to our chain backend to check every UTXO for channel announcement. Assumevalid until we run through them and only in case of failure prune channel.

Add to add UserConfig access in Router as it would be a user-configured value.

[TheBlueMatt]

We already support assumevalid-ing...I'm not really sure what the value is to having the user go back and remove things which are invalid - if they don't support chain queries, they probably filter the chain download and wont/shouldnt download a ton of channel txn.

[ariard]

My intuition was than get_chain_utxo could be reused by client for another component and you may want chain access for this one (like checking inputs for splicing) and don't want to tie ChainWatchInterface implementation on how you expect a consumer interface to behave.

Whatever, how to get assumevalid (as it's a LN-node targeted feature now) should be better documented (maybe in the Router top-level documentation)

[TheBlueMatt]

It should definitely be better documented. I also wouldn’t object to a different API since the trend has been to split up chain-access stuff. I’m not sure what you’d reuse get_chain_utxo for - splice is a wallet action and requires a get_wallet_utxo, not any one (which would be on a different interface).

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On Feb 10, 2020, at 19:50, Antoine Riard ***@***.***> wrote:  My intuition was than get_chain_utxo could be reused by client for another component and you may want chain access for this one (like checking inputs for splicing) and don't want to tie ChainWatchInterface implementation on how you expect a consumer interface to behave. Whatever, how to get assumevalid (as it's a LN-node targeted feature now) should be better documented (maybe in the Router top-level documentation) — You are receiving this because you commented. Reply to this email directly, view it on GitHub, or unsubscribe.

[ariard]

I’m not sure what you’d reuse get_chain_utxo for - splice is a wallet action and requires a get_wallet_utxo, not any one (which would be on a different interface).

I see get_chain_utxo has a way to verify utxo you get from LN wire, with tx composition you may have to verify inputs announced by your counter-party, but yes we should start thinking how to make dual-funding/splicing support the less restrictive we can.

[TheBlueMatt]

Splicing absolutely should not require any knowledge of the chain to verify some data your counterparty provided you - until its confirmed, its just something you signed for them in case they can do something.