bitcoin-s/docs/wallet/wallet-rescan.md
Chris Stewart 4b83286922
2022 07 25 wallet api refactor (#4545)
* Move MockChainQueryApi/NodeApi out of BaseWalletTest

* refactor BitcoinSServerMain.start() to return WalletHolder

* Add walletConfig to WalletWithBitcoind

* Move findOutputsBeingSpent into WalletApi

* Add WalletApi.clearAllAddresses(), HDWalletApi.{findAccount, getnewaddress(account)}

* Add HDWalletApi.fundRawTransaction() with an account as parameter

* Add WalletApi.findByScriptPubKey()

* Fix lots of tests in WalletIntegrationTest

* Create WalletApi.processOurTransaction()

* Get things compiling

* Fix tag integration test

* Refactor AnyDLCHDWalletApi -> DLCNeutrinoHDWalletApi

* Fix docs

* Get postgres tests passing locally

* Move initBalance map before calling callback in CallBackUtilTest

* Get compile working, rename to destroyOnlyWalletWithBitcoindCached

* Fix docs

* Fix missing destroyWalletAppConfig

* Fix scalafmt

* Fix bug in dlcWalletTest where wallet db thread pools weren't being shutdown after unit test completes

* Empty commit
2022-07-31 08:04:39 -05:00

126 lines
4.1 KiB
Markdown

---
title: Wallet Rescans
id: wallet-rescan
---
With [BIP157](https://github.com/bitcoin/bips/blob/master/bip-0157.mediawiki) you can cache block filters locally to use
later for rescans in the case you need to restore your wallets. Our [chain](../chain/chain.md) project gives us
an API with the ability to query for filters.
### Rescan from CLI
To execute a rescan from the cli because you are restoring a wallet or it has gotten out of sync is fairly simple.
If you have an empty wallet it can be done by simply calling rescan
```bash
./bitcoin-s-cli rescan
```
If your wallet is not empty then you will need to call it with the force command
```bash
./bitcoin-s-cli rescan --force
```
You can also specify start and stop heights
```bash
./bitcoin-s-cli rescan --start <start height> --stop <stop height>
```
By default, if you do not set the start height, the rescan will begin at your wallet's creation time.
If you wish to ignore this and start from genesis use the `ignorecreationtime` flag
```bash
./bitcoin-s-cli rescan --ignorecreationtime
```
### Code Example
You can rescan your wallet with filters with [`WalletApi.rescanNeutrinoWallet()`](https://github.com/bitcoin-s/bitcoin-s/blob/master/core/src/main/scala/org/bitcoins/core/api/wallet/NeutrinoWalletApi.scala#L77)
To run this example you need to make sure you have access to a bitcoind binary.
You can download this with bitcoin-s by doing `sbt downloadBitcoind`
```scala mdoc:invisible
import org.bitcoins.testkit.chain.MockChainQueryApi
import org.bitcoins.testkit.BitcoinSTestAppConfig
import org.bitcoins.testkit.fixtures._
import org.bitcoins.testkit.wallet._
import org.bitcoins.rpc.client.common.BitcoindVersion
import org.bitcoins.server.BitcoinSAppConfig
import org.bitcoins.wallet.config.WalletAppConfig
import org.bitcoins.wallet.WalletCallbacks
import org.bitcoins.testkit.node.MockNodeApi
import akka.actor.ActorSystem
import scala.concurrent._
import scala.concurrent.duration.DurationInt
```
```scala mdoc:compile-only
//we need an actor system and app config to power this
implicit val system: ActorSystem = ActorSystem(s"wallet-rescan-example")
implicit val ec: ExecutionContext = system.dispatcher
implicit val appConfig: BitcoinSAppConfig = BitcoinSTestAppConfig.getNeutrinoTestConfig()
implicit val walletAppConfig: WalletAppConfig = appConfig.walletConf
//ok now let's spin up a bitcoind and a bitcoin-s wallet with funds in it
val walletWithBitcoindF = for {
walletWithBitcoind <- BitcoinSWalletTest.fundedWalletAndBitcoind(
Some(BitcoindVersion.newest),
MockNodeApi,
MockChainQueryApi,
WalletCallbacks.empty)
} yield walletWithBitcoind
val walletF = walletWithBitcoindF.map(_.wallet)
val bitcoindF = walletWithBitcoindF.map(_.bitcoind)
//let's see what our initial wallet balance is
val initBalanceF = for {
w <- walletF
balance <- w.getBalance()
} yield {
println(s"Initial wallet balance=${balance}")
balance
}
//ok great! We have money in the wallet to start,
//now let's delete our internal tables that hold our utxos
//and addresses so that we end up with a 0 balance
val clearedWalletF = for {
w <- walletF
_ <- initBalanceF
clearedWallet <- w.clearAllUtxos()
zeroBalance <- clearedWallet.getBalance()
} yield {
println(s"Balance after clearing utxos: ${zeroBalance}")
clearedWallet
}
//we need to pick how many addresses we want to generate off of our keychain
//when doing a rescan, this means we are generating 100 addrsses
//and then looking for matches. If we find a match, we generate _another_
//100 fresh addresses and search those. We keep doing this until we find
//100 addresses that do not contain a match.
val addrBatchSize = 100
//ok now that we have a cleared wallet, we need to rescan and find our fudns again!
val rescannedBalanceF = for {
_ <- clearedWalletF
w <- walletF
_ <- w.fullRescanNeutrinoWallet(addrBatchSize)
balanceAfterRescan <- w.getBalance()
} yield {
println(s"Wallet balance after rescan: ${balanceAfterRescan}")
()
}
//cleanup
val cleanupF = for {
_ <- rescannedBalanceF
walletWithBitcoind <- walletWithBitcoindF
_ <- BitcoinSWalletTest.destroyWalletWithBitcoind(walletWithBitcoind)
} yield ()
Await.result(cleanupF, 60.seconds)
```