Re: Filtering out watched txs

[Anton]

Okay, I think I'll actually take this code out of bitcoinj and make a 
custom Transaction wrapper in my project which I'll be using for filtering 
for now.
LN transactions indeed don't seem to belong to those "payments" since 
they're off-chain, no way for bitcoinj to even catch them, except for 
funding/breach/closing txs which are on-chain.


понедельник, 10 июля 2017 г., 23:26:34 UTC+3 пользователь Andreas 
Schildbach написал:
>
> There is currently no way to have bitcoinj filter the list of 
> transactions, you'll have to do that yourself ATM. 
>
> We always envisioned having a second, more usecase-oriented list of 
> "payments". This would then represent the list shown to the user. 
> Lightning payments could be visible there too in future (although LN is 
> a layer on top, so not sure if it's the right thing). So far, work on 
> this hasn't started. 
>
>
> On 07/08/2017 09:07 AM, Anton wrote: 
> > After an LN payment channel is open there is a constant need to monitor 
> > if it's P2WSH output has been spent, I use `addWatchedScripts` for that 
> > and it works great. The only UX level problem with this approach is when 
> > P2WSH output does get spent a user will see a strange spending tx which 
> > changes nothing in wallet, this may confuse many. 
> > 
> > So what is needed is a way to filter out purely watched transactions 
> > before displaying a tx list on a UI. Currently I do this as follows: 
> > 
> https://github.com/btcontract/bitcoinj/commit/8475c850ef7b5d07ae7b30d605362c2dbea8d0d5,
>  
>
> > the code is based on a fact that a purely watched tx does not change 
> > wallet's balance so it's `getValue` is 0 when watched outputs and inputs 
> > are excluded so we can use that when deciding if a given tx should be 
> > displayed. 
> > 
> > This works but I don't like an approach because it feels hacky 
> > (`getValue` is essentially duplicated in `getExcludeWatchedValue`), 
> > perhaps there are much better ways to do that? 
> > 
> > Other simple approaches I was thinking of which won't do: 
> > 
> > - Immediately stop watching a P2WSH output script once it is spent so a 
> > related watched tx won't be shown anymore (won't do because a peer may 
> > attempt to spend a P2WSH output multiple times using different commit 
> > txs which will create a race of double spends and there's no telling 
> > which of them will win, so we need to continue watching a script even 
> > after the first spend is seen to react accordingly). 
> > 
> > - Just filter out all txs which contain a watched P2WSH output in their 
> > inputs (won't do since that will filter out mutual closing tx which does 
> > spend a P2WSH output but is legitimate since it sends money back to 
> > user's wallet) 
> > 
> > Thanks! 
> > 
> > -- 
> > You received this message because you are subscribed to the Google 
> > Groups "bitcoinj" group. 
> > To unsubscribe from this group and stop receiving emails from it, send 
> > an email to bitcoinj+u...@googlegroups.com  
> > . 
> > For more options, visit https://groups.google.com/d/optout. 
>
>
>

-- 
You received this message because you are subscribed to the Google Groups 
"bitcoinj" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to bitcoinj+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Re: Filtering out watched txs

[Andreas Schildbach]

There is currently no way to have bitcoinj filter the list of
transactions, you'll have to do that yourself ATM.

We always envisioned having a second, more usecase-oriented list of
"payments". This would then represent the list shown to the user.
Lightning payments could be visible there too in future (although LN is
a layer on top, so not sure if it's the right thing). So far, work on
this hasn't started.


On 07/08/2017 09:07 AM, Anton wrote:
> After an LN payment channel is open there is a constant need to monitor
> if it's P2WSH output has been spent, I use `addWatchedScripts` for that
> and it works great. The only UX level problem with this approach is when
> P2WSH output does get spent a user will see a strange spending tx which
> changes nothing in wallet, this may confuse many. 
> 
> So what is needed is a way to filter out purely watched transactions
> before displaying a tx list on a UI. Currently I do this as follows:
> https://github.com/btcontract/bitcoinj/commit/8475c850ef7b5d07ae7b30d605362c2dbea8d0d5,
> the code is based on a fact that a purely watched tx does not change
> wallet's balance so it's `getValue` is 0 when watched outputs and inputs
> are excluded so we can use that when deciding if a given tx should be
> displayed.
> 
> This works but I don't like an approach because it feels hacky
> (`getValue` is essentially duplicated in `getExcludeWatchedValue`),
> perhaps there are much better ways to do that?
> 
> Other simple approaches I was thinking of which won't do:
> 
> - Immediately stop watching a P2WSH output script once it is spent so a
> related watched tx won't be shown anymore (won't do because a peer may
> attempt to spend a P2WSH output multiple times using different commit
> txs which will create a race of double spends and there's no telling
> which of them will win, so we need to continue watching a script even
> after the first spend is seen to react accordingly).
> 
> - Just filter out all txs which contain a watched P2WSH output in their
> inputs (won't do since that will filter out mutual closing tx which does
> spend a P2WSH output but is legitimate since it sends money back to
> user's wallet)
> 
> Thanks!
> 
> -- 
> You received this message because you are subscribed to the Google
> Groups "bitcoinj" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to bitcoinj+unsubscr...@googlegroups.com
> .
> For more options, visit https://groups.google.com/d/optout.


-- 
You received this message because you are subscribed to the Google Groups 
"bitcoinj" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to bitcoinj+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.