Negotiate higher version against electrum server to show balance on token addresses

[imaginaryusername]

Per the fulcrum get_balance method, BCH balance on "token" addresses will only be shown if version is >1.5. This has led to results such as https://chipnet.imaginary.cash/address/bchtest:pzn85ff863dnceq0gt5sd88e00afchyur5jasutc0s?sort=desc&limit=10&offset=10 where BCH balances on token'd UTXOs are excluded, and the overall balance is shown as zero.

I don't know where it is, but since token support is added the explorer should be able to report a version of 1.5.0 and make Fulcrum report BCH balance on tokens again.

[sickpig]

actually we are using @dagurval rostrum as electrumX protocol implementation.

having said that I think that the version of rostrum we are using (8.1.0) support the token_filter optional parameter for the get_balance so it seems like just a matter of adapting the /address/ view.

will work on that

[sickpig]

@imaginaryusername

Little heads up

So I set up py script that establishes a connection to your fulcrum instance @ chipnet.imaginary.cash:50001, negotiates protocol version to 1.5 and then issue a get_balance for this address bchtest:pzn85ff863dnceq0gt5sd88e00afchyur5jasutc0s

if ”include_tokens” optional param is passed to get_balance the result we have is:

{
  "id": 0,
  "jsonrpc": "2.0",
  "result": {
    "confirmed": 16000,
    "unconfirmed": 0
  }
}

if ”exclude_tokens” optional param is passed to get_balance the result we have is:

{
  "id": 0,
  "jsonrpc": "2.0",
  "result": {
    "confirmed": 0,
    "unconfirmed": 0
  }
}

[imaginaryusername]

The docs call it token_filter at Fulcrum too but yes that does look right to me.

[sickpig]

The docs call it token_filter at Fulcrum too but yes that does look right to me.

rostrum calls the filter parameter the same, namelytoken_filter, exclude_tokens is actually one of the 3 possible values for that param, see:

https://bitcoinunlimited.gitlab.io/rostrum/protocol/methods/#blockchainaddressget_balance

I'm going to open a PR to fix the problem you described in the OP, namely negotiate version 1.5 for electrum protocol (only if using Fulcrum, 1.4 is enough for Rostrum).

Having said that I think that Fulcrum 1.9.1 behaviour is not coherent with the timing of network upgrades activation, I mean any clients speaking protocol 1.4 should not be aware of token existence, so what's the point of excluding UTXOs from the computation of address amount in case they are "attached" to a cashtoken?

maybe something to forward to @cculianu

[imaginaryusername]

This was a result of two goals:

1. The desire to not have 1.4 clients spend tokens accidentally. They already can't do that for the most part since cashtokens utxo signing method is changed.
2. The desire to not have 1.4 clients see "unspendable" UTXOs they cannot understand, both in code and in meatspace

Removing visibility of token-attached sats to 1.4 clients satisfy both of these goals. If we forward the sats to them anyway, upon receipt there'll be some unspendable and unexplained sats which can cause UX problems.

[sickpig]

This was a result of two goals:

1. The desire to not have 1.4 clients spend tokens accidentally. They already can't do that for the most part since cashtokens utxo signing method is changed.
2. The desire to not have 1.4 clients see "unspendable" UTXOs they cannot understand, both in code and in meatspace

Removing visibility of token-attached sats to 1.4 clients satisfy both of these goals. If we forward the sats to them anyway, upon receipt there'll be some unspendable and unexplained sats which can cause UX problems.

mmmm I have to say that I found the above arguments weird.

Just for the sake of clarity, let me explain my point of view on this matter.

Suppose for a moment we erroneously send UTXOs that represents cashtokens to a client that speaks 1.4 protocol only.

Your point is: since it is probably impossible (not certain) that they won't be able to spend those UTXOs due to signature scheme changes why bother showing the UTXOs among the total amount.

My point is:

• once someone send cashtoken to an non-token aware client those tokens are, for lack of better words, "gone"/"burnt"
  • as you said probably the client won't be able to send it back to you
  • and if it's able to do sign properly he will probably use it as inputs to normal BCH tx.
• if those bch utxos become unspendable I would rather make the result ("error") of the unwanted transfer apparent to the receiver rather than not, for 2 main reasons:
  • this would probably push the client operator to upgrade to 1.5 protocol a
  • this would make aware the client operator that he is now owning something even if it is not something he wanted to in the first place, it's always better to be aware of those kind of things rather that not.

just my 2 cents.