wallet: add new PSBT funding and finalizing methods

go.mod

@@ -4,6 +4,7 @@ require (
 	github.com/btcsuite/btcd v0.20.1-beta.0.20200513120220-b470eee47728
 	github.com/btcsuite/btclog v0.0.0-20170628155309-84c8d2346e9f
 	github.com/btcsuite/btcutil v0.0.0-20190425235716-9e5f4b9a998d
+	github.com/btcsuite/btcutil/psbt v1.0.3-0.20200826194809-5f93e33af2b0
 	github.com/btcsuite/btcwallet/wallet/txauthor v1.0.0
 	github.com/btcsuite/btcwallet/wallet/txrules v1.0.0
 	github.com/btcsuite/btcwallet/walletdb v1.3.3

go.sum

@@ -11,6 +11,8 @@ github.com/btcsuite/btclog v0.0.0-20170628155309-84c8d2346e9f h1:bAs4lUbRJpnnkd9
 github.com/btcsuite/btclog v0.0.0-20170628155309-84c8d2346e9f/go.mod h1:TdznJufoqS23FtqVCzL0ZqgP5MqXbb4fg/WgDys70nA=
 github.com/btcsuite/btcutil v0.0.0-20190425235716-9e5f4b9a998d h1:yJzD/yFppdVCf6ApMkVy8cUxV0XrxdP9rVf6D87/Mng=
 github.com/btcsuite/btcutil v0.0.0-20190425235716-9e5f4b9a998d/go.mod h1:+5NJ2+qvTyV9exUAL/rxXi3DcLg2Ts+ymUAY5y4NvMg=
+github.com/btcsuite/btcutil/psbt v1.0.3-0.20200826194809-5f93e33af2b0 h1:3Zumkyl6PWyHuVJ04me0xeD9CnPOhNgeGpapFbzy7O4=
+github.com/btcsuite/btcutil/psbt v1.0.3-0.20200826194809-5f93e33af2b0/go.mod h1:LVveMu4VaNSkIRTZu2+ut0HDBRuYjqGocxDMNS1KuGQ=
 github.com/btcsuite/go-socks v0.0.0-20170105172521-4720035b7bfd h1:R/opQEbFEy9JGkIguV40SvRY1uliPX8ifOvi6ICsFCw=
 github.com/btcsuite/go-socks v0.0.0-20170105172521-4720035b7bfd/go.mod h1:HHNXQzUsZCxOoE+CPiyCTO6x34Zs86zZUiwtpXoGdtg=
 github.com/btcsuite/goleveldb v0.0.0-20160330041536-7834afc9e8cd/go.mod h1:F+uVaaLLH7j4eDXPRvw78tMflu7Ie2bzYOH4Y8rRKBY=

wallet/createtx.go

@@ -120,7 +120,7 @@ func (w *Wallet) txToOutputs(outputs []*wire.TxOut, account uint32,
 	}
 	defer dbtx.Rollback()
 
-	addrmgrNs := dbtx.ReadWriteBucket(waddrmgrNamespaceKey)
+	addrmgrNs, changeSource := w.addrMgrWithChangeSource(dbtx, account)
 
 	// Get current block's height and hash.
 	bs, err := chainClient.BlockStamp()
@@ -134,28 +134,6 @@ func (w *Wallet) txToOutputs(outputs []*wire.TxOut, account uint32,
 	}
 
 	inputSource := makeInputSource(eligible)
-	changeSource := func() ([]byte, error) {
-		// Derive the change output script. We'll use the default key
-		// scope responsible for P2WPKH addresses to do so. As a hack to
-		// allow spending from the imported account, change addresses
-		// are created from account 0.
-		var changeAddr btcutil.Address
-		var err error
-		changeKeyScope := waddrmgr.KeyScopeBIP0084
-		if account == waddrmgr.ImportedAddrAccount {
-			changeAddr, err = w.newChangeAddress(
-				addrmgrNs, 0, changeKeyScope,
-			)
-		} else {
-			changeAddr, err = w.newChangeAddress(
-				addrmgrNs, account, changeKeyScope,
-			)
-		}
-		if err != nil {
-			return nil, err
-		}
-		return txscript.PayToAddrScript(changeAddr)
-	}
 	tx, err = txauthor.NewUnsignedTransaction(outputs, feeSatPerKb,
 		inputSource, changeSource)
 	if err != nil {
@@ -270,6 +248,37 @@ func (w *Wallet) findEligibleOutputs(dbtx walletdb.ReadTx, account uint32, minco
 	return eligible, nil
 }
 
+// addrMgrWithChangeSource returns the address manager bucket and a change
+// source function that returns change addresses from said address manager.
+func (w *Wallet) addrMgrWithChangeSource(dbtx walletdb.ReadWriteTx,
+	account uint32) (walletdb.ReadWriteBucket, txauthor.ChangeSource) {
+
+	addrmgrNs := dbtx.ReadWriteBucket(waddrmgrNamespaceKey)
+	changeSource := func() ([]byte, error) {
+		// Derive the change output script. We'll use the default key
+		// scope responsible for P2WPKH addresses to do so. As a hack to
+		// allow spending from the imported account, change addresses
+		// are created from account 0.
+		var changeAddr btcutil.Address
+		var err error
+		changeKeyScope := waddrmgr.KeyScopeBIP0084
+		if account == waddrmgr.ImportedAddrAccount {
+			changeAddr, err = w.newChangeAddress(
+				addrmgrNs, 0, changeKeyScope,
+			)
+		} else {
+			changeAddr, err = w.newChangeAddress(
+				addrmgrNs, account, changeKeyScope,
+			)
+		}
+		if err != nil {
+			return nil, err
+		}
+		return txscript.PayToAddrScript(changeAddr)
+	}
+	return addrmgrNs, changeSource
+}
+
 // validateMsgTx verifies transaction input scripts for tx.  All previous output
 // scripts from outputs redeemed by the transaction, in the same order they are
 // spent, must be passed in the prevScripts slice.

wallet/createtx_test.go

@@ -18,6 +18,14 @@ import (
 	"github.com/btcsuite/btcwallet/wtxmgr"
 )
 
+var (
+	testBlockHash, _ = chainhash.NewHashFromStr(
+		"00000000000000017188b968a371bab95aa43522665353b646e41865abae" +
+			"02a4",
+	)
+	testBlockHeight int32 = 276425
+)
+
 // TestTxToOutput checks that no new address is added to he database if we
 // request a dry run of the txToOutputs call. It also makes sure a subsequent
 // non-dry run call produces a similar transaction to the dry-run.
@@ -45,41 +53,7 @@ func TestTxToOutputsDryRun(t *testing.T) {
 			txOut,
 		},
 	}
-
-	var b bytes.Buffer
-	if err := incomingTx.Serialize(&b); err != nil {
-		t.Fatalf("unable to serialize tx: %v", err)
-	}
-	txBytes := b.Bytes()
-
-	rec, err := wtxmgr.NewTxRecord(txBytes, time.Now())
-	if err != nil {
-		t.Fatalf("unable to create tx record: %v", err)
-	}
-
-	// The block meta will be inserted to tell the wallet this is a
-	// confirmed transaction.
-	blockHash, _ := chainhash.NewHashFromStr(
-		"00000000000000017188b968a371bab95aa43522665353b646e41865abae02a4")
-	block := &wtxmgr.BlockMeta{
-		Block: wtxmgr.Block{Hash: *blockHash, Height: 276425},
-		Time:  time.Unix(1387737310, 0),
-	}
-
-	if err := walletdb.Update(w.db, func(tx walletdb.ReadWriteTx) error {
-		ns := tx.ReadWriteBucket(wtxmgrNamespaceKey)
-		err = w.TxStore.InsertTx(ns, rec, block)
-		if err != nil {
-			return err
-		}
-		err = w.TxStore.AddCredit(ns, rec, block, 0, false)
-		if err != nil {
-			return err
-		}
-		return nil
-	}); err != nil {
-		t.Fatalf("failed inserting tx: %v", err)
-	}
+	addUtxo(t, w, incomingTx)
 
 	// Now tell the wallet to create a transaction paying to the specified
 	// outputs.
@@ -175,3 +149,43 @@ func TestTxToOutputsDryRun(t *testing.T) {
 			"than wet run")
 	}
 }
+
+// addUtxo add the given transaction to the wallet's database marked as a
+// confirmed UTXO .
+func addUtxo(t *testing.T, w *Wallet, incomingTx *wire.MsgTx) {
+	var b bytes.Buffer
+	if err := incomingTx.Serialize(&b); err != nil {
+		t.Fatalf("unable to serialize tx: %v", err)
+	}
+	txBytes := b.Bytes()
+
+	rec, err := wtxmgr.NewTxRecord(txBytes, time.Now())
+	if err != nil {
+		t.Fatalf("unable to create tx record: %v", err)
+	}
+
+	// The block meta will be inserted to tell the wallet this is a
+	// confirmed transaction.
+	block := &wtxmgr.BlockMeta{
+		Block: wtxmgr.Block{
+			Hash:   *testBlockHash,
+			Height: testBlockHeight,
+		},
+		Time: time.Unix(1387737310, 0),
+	}
+
+	if err := walletdb.Update(w.db, func(tx walletdb.ReadWriteTx) error {
+		ns := tx.ReadWriteBucket(wtxmgrNamespaceKey)
+		err = w.TxStore.InsertTx(ns, rec, block)
+		if err != nil {
+			return err
+		}
+		err = w.TxStore.AddCredit(ns, rec, block, 0, false)
+		if err != nil {
+			return err
+		}
+		return nil
+	}); err != nil {
+		t.Fatalf("failed inserting tx: %v", err)
+	}
+}