`globalbalance` returns wrong onchain balance

[rorp]

eclair-cli globalbalance returns these values

"onChain": {
    "confirmed": x.yyyyyyy9000000001,
    "unconfirmed": 0
  }

whereas bitcoin-cli getbalace returns x.yyyyyyy9.

Eclair found 0.00000000000000001 somewhere.

[t-bast]

@pm47 could that be related to something eclair does, or is that just a rounding issue from scala's double?

[pm47]

My bet is a conversion error from BigDecimal to Decimal at serialization (we should probably use Formats.withBigDecimal() and not convert to Decimal):

eclair/eclair-core/src/main/scala/fr/acinq/eclair/json/JsonSerializers.scala

Lines 169 to 171 in e298ba9

	object BtcSerializer extends MinimalSerializer({
	case x: Btc => JDecimal(x.toDouble)
	})

We do use Formats.withBigDecimal() to parse bitcoind responses, the rounding could potentially come from here too:

eclair/eclair-core/src/main/scala/fr/acinq/eclair/blockchain/bitcoind/rpc/BasicBitcoinJsonRPCClient.scala

Line 37 in e298ba9

implicit val formats: Formats = DefaultFormats.withBigDecimal +

Or when summing individual amounts to build the CorrectedOnChainBalance (note that we don't call getbalance):

eclair/eclair-core/src/main/scala/fr/acinq/eclair/balance/CheckBalance.scala

Lines 293 to 296 in e298ba9

	detailed = utxos.foldLeft(DetailedBalance()) {
	case (total, utxo) if utxo.confirmations == 0 => total.modify(_.unconfirmed).using(_ + utxo.amount)
	case (total, utxo) => total.modify(_.confirmed).using(_ + utxo.amount)
	}