From 908d82acdb06adc871e54dd14843249915f24406 Mon Sep 17 00:00:00 2001
From: Olaoluwa Osuntokun <laolu32@gmail.com>
Date: Wed, 6 Mar 2019 18:22:46 -0800
Subject: [PATCH] loop: extract code from client package into new loop primary
 package

---
 client/client.go => client.go                 | 25 ++++---
 client/log.go                                 | 24 -------
 client/utils.go                               | 20 ------
 client/client_test.go => client_test.go       |  2 +-
 client/config.go => config.go                 |  2 +-
 client/executor.go => executor.go             |  6 +-
 client/interface.go => interface.go           | 69 +++---------------
 lndclient/chainnotifier_client.go             |  6 +-
 lndclient/lnd_services.go                     |  4 +-
 lndclient/signer_client.go                    |  4 +-
 lndclient/walletkit_client.go                 |  6 +-
 log.go                                        | 70 +++++++++++++++++++
 ...server_mock_test.go => server_mock_test.go |  2 +-
 .../store_mock_test.go => store_mock_test.go  |  2 +-
 client/swap.go => swap.go                     |  2 +-
 ..._server_client.go => swap_server_client.go |  2 +-
 test/lightning_client_mock.go                 |  4 +-
 ...testcontext_test.go => testcontext_test.go | 11 +--
 client/uncharge.go => uncharge.go             |  9 ++-
 uncharge_state.go                             |  1 +
 client/uncharge_test.go => uncharge_test.go   |  2 +-
 21 files changed, 126 insertions(+), 147 deletions(-)
 rename client/client.go => client.go (94%)
 delete mode 100644 client/log.go
 delete mode 100644 client/utils.go
 rename client/client_test.go => client_test.go (99%)
 rename client/config.go => config.go (95%)
 rename client/executor.go => executor.go (98%)
 rename client/interface.go => interface.go (77%)
 create mode 100644 log.go
 rename client/server_mock_test.go => server_mock_test.go (99%)
 rename client/store_mock_test.go => store_mock_test.go (99%)
 rename client/swap.go => swap.go (99%)
 rename client/swap_server_client.go => swap_server_client.go (99%)
 rename client/testcontext_test.go => testcontext_test.go (95%)
 rename client/uncharge.go => uncharge.go (99%)
 create mode 100644 uncharge_state.go
 rename client/uncharge_test.go => uncharge_test.go (99%)

diff --git a/client/client.go b/client.go
similarity index 94%
rename from client/client.go
rename to client.go
index 359650b..dc11b9b 100644
--- a/client/client.go
+++ b/client.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"context"
@@ -46,8 +46,8 @@ var (
 	republishDelay = 10 * time.Second
 )
 
-// Client performs the client side part of swaps. This interface exists to
-// be able to implement a stub.
+// Client performs the client side part of swaps. This interface exists to be
+// able to implement a stub.
 type Client struct {
 	started uint32 // To be used atomically.
 	errChan chan error
@@ -118,9 +118,9 @@ func (s *Client) GetUnchargeSwaps() ([]*PersistentUncharge, error) {
 }
 
 // Run is a blocking call that executes all swaps. Any pending swaps are
-// restored from persistent storage and resumed.  Subsequent updates
-// will be sent through the passed in statusChan. The function can be
-// terminated by cancelling the context.
+// restored from persistent storage and resumed.  Subsequent updates will be
+// sent through the passed in statusChan. The function can be terminated by
+// cancelling the context.
 func (s *Client) Run(ctx context.Context,
 	statusChan chan<- SwapInfo) error {
 
@@ -213,11 +213,10 @@ func (s *Client) resumeSwaps(ctx context.Context,
 	}
 }
 
-// Uncharge initiates a uncharge swap. It blocks until the swap is
-// initiation with the swap server is completed (typically this takes
-// only a short amount of time). From there on further status
-// information can be acquired through the status channel returned from
-// the Run call.
+// Uncharge initiates a uncharge swap. It blocks until the swap is initiation
+// with the swap server is completed (typically this takes only a short amount
+// of time). From there on further status information can be acquired through
+// the status channel returned from the Run call.
 //
 // When the call returns, the swap has been persisted and will be
 // resumed automatically after restarts.
@@ -258,8 +257,8 @@ func (s *Client) Uncharge(globalCtx context.Context,
 }
 
 // UnchargeQuote takes a Uncharge amount and returns a break down of estimated
-// costs for the client. Both the swap server and the on-chain fee estimator are
-// queried to get to build the quote response.
+// costs for the client. Both the swap server and the on-chain fee estimator
+// are queried to get to build the quote response.
 func (s *Client) UnchargeQuote(ctx context.Context,
 	request *UnchargeQuoteRequest) (*UnchargeQuote, error) {
 
diff --git a/client/log.go b/client/log.go
deleted file mode 100644
index d510225..0000000
--- a/client/log.go
+++ /dev/null
@@ -1,24 +0,0 @@
-package client
-
-import (
-	"github.com/btcsuite/btclog"
-	"os"
-)
-
-// log is a logger that is initialized with no output filters.  This
-// means the package will not perform any logging by default until the caller
-// requests it.
-var (
-	backendLog     = btclog.NewBackend(logWriter{})
-	logger         = backendLog.Logger("CLIENT")
-	servicesLogger = backendLog.Logger("SERVICES")
-)
-
-// logWriter implements an io.Writer that outputs to both standard output and
-// the write-end pipe of an initialized log rotator.
-type logWriter struct{}
-
-func (logWriter) Write(p []byte) (n int, err error) {
-	os.Stdout.Write(p)
-	return len(p), nil
-}
diff --git a/client/utils.go b/client/utils.go
deleted file mode 100644
index 8937bc8..0000000
--- a/client/utils.go
+++ /dev/null
@@ -1,20 +0,0 @@
-package client
-
-import (
-	"errors"
-
-	"github.com/btcsuite/btcd/wire"
-)
-
-// getTxInputByOutpoint returns a tx input based on a given input outpoint.
-func getTxInputByOutpoint(tx *wire.MsgTx, input *wire.OutPoint) (
-	*wire.TxIn, error) {
-
-	for _, in := range tx.TxIn {
-		if in.PreviousOutPoint == *input {
-			return in, nil
-		}
-	}
-
-	return nil, errors.New("input not found")
-}
diff --git a/client/client_test.go b/client_test.go
similarity index 99%
rename from client/client_test.go
rename to client_test.go
index 31d2d04..6600b03 100644
--- a/client/client_test.go
+++ b/client_test.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"bytes"
diff --git a/client/config.go b/config.go
similarity index 95%
rename from client/config.go
rename to config.go
index 2d3b017..1f4086a 100644
--- a/client/config.go
+++ b/config.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"time"
diff --git a/client/executor.go b/executor.go
similarity index 98%
rename from client/executor.go
rename to executor.go
index c6a4931..6116d10 100644
--- a/client/executor.go
+++ b/executor.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"context"
@@ -21,6 +21,8 @@ type executorConfig struct {
 }
 
 // executor is responsible for executing swaps.
+//
+// TODO(roasbeef): rename to SubSwapper
 type executor struct {
 	wg            sync.WaitGroup
 	newSwaps      chan genericSwap
@@ -91,6 +93,7 @@ func (s *executor) run(mainCtx context.Context,
 	nextSwapID := 0
 	for {
 		select {
+
 		case newSwap := <-s.newSwaps:
 			queue := queue.NewConcurrentQueue(10)
 			queue.Start()
@@ -115,6 +118,7 @@ func (s *executor) run(mainCtx context.Context,
 			}()
 
 			nextSwapID++
+
 		case doneID := <-swapDoneChan:
 			queue, ok := blockEpochQueues[doneID]
 			if !ok {
diff --git a/client/interface.go b/interface.go
similarity index 77%
rename from client/interface.go
rename to interface.go
index f8d15fa..bed2e5c 100644
--- a/client/interface.go
+++ b/interface.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"time"
@@ -29,9 +29,9 @@ type UnchargeRequest struct {
 	MaxPrepayRoutingFee btcutil.Amount
 
 	// MaxSwapFee is the maximum we are willing to pay the server for the
-	// swap. This value is not disclosed in the swap initiation call, but if
-	// the server asks for a higher fee, we abort the swap. Typically this
-	// value is taken from the response of the UnchargeQuote call. It
+	// swap. This value is not disclosed in the swap initiation call, but
+	// if the server asks for a higher fee, we abort the swap. Typically
+	// this value is taken from the response of the UnchargeQuote call. It
 	// includes the prepay amount.
 	MaxSwapFee btcutil.Amount
 
@@ -66,28 +66,6 @@ type UnchargeRequest struct {
 	UnchargeChannel *uint64
 }
 
-// UnchargeContract contains the data that is serialized to persistent storage for
-// pending swaps.
-type UnchargeContract struct {
-	SwapContract
-
-	DestAddr btcutil.Address
-
-	SwapInvoice string
-
-	// MaxSwapRoutingFee is the maximum off-chain fee in msat that may be
-	// paid for the swap payment to the server.
-	MaxSwapRoutingFee btcutil.Amount
-
-	// SweepConfTarget specifies the targeted confirmation target for the
-	// client sweep tx.
-	SweepConfTarget int32
-
-	// UnchargeChannel is the channel to uncharge. If zero, any channel may
-	// be used.
-	UnchargeChannel *uint64
-}
-
 // UnchargeSwapInfo contains status information for a uncharge swap.
 type UnchargeSwapInfo struct {
 	UnchargeContract
@@ -152,7 +130,8 @@ type UnchargeTerms struct {
 	// SwapFeeRate is the variable fee in parts per million.
 	SwapFeeRate int64
 
-	// PrepayAmt is the fixed part of the swap fee that needs to be prepaid.
+	// PrepayAmt is the fixed part of the swap fee that needs to be
+	// prepaid.
 	PrepayAmt btcutil.Amount
 
 	// MinSwapAmount is the minimum amount that the server requires for a
@@ -172,42 +151,10 @@ type UnchargeTerms struct {
 	SwapPaymentDest [33]byte
 }
 
-// SwapContract contains the base data that is serialized to persistent storage
-// for pending swaps.
-type SwapContract struct {
-	Preimage        lntypes.Preimage
-	AmountRequested btcutil.Amount
-
-	PrepayInvoice string
-
-	SenderKey   [33]byte
-	ReceiverKey [33]byte
-
-	CltvExpiry int32
-
-	// MaxPrepayRoutingFee is the maximum off-chain fee in msat that may be
-	// paid for the prepayment to the server.
-	MaxPrepayRoutingFee btcutil.Amount
-
-	// MaxSwapFee is the maximum we are willing to pay the server for the
-	// swap.
-	MaxSwapFee btcutil.Amount
-
-	// MaxMinerFee is the maximum in on-chain fees that we are willing to
-	// spend.
-	MaxMinerFee btcutil.Amount
-
-	// InitiationHeight is the block height at which the swap was initiated.
-	InitiationHeight int32
-
-	// InitiationTime is the time at which the swap was initiated.
-	InitiationTime time.Time
-}
-
 // SwapInfoKit contains common swap info fields.
 type SwapInfoKit struct {
-	// Hash is the sha256 hash of the preimage that unlocks the htlcs. It is
-	// used to uniquely identify this swap.
+	// Hash is the sha256 hash of the preimage that unlocks the htlcs. It
+	// is used to uniquely identify this swap.
 	Hash lntypes.Hash
 
 	// LastUpdateTime is the time of the last update of this swap.
diff --git a/lndclient/chainnotifier_client.go b/lndclient/chainnotifier_client.go
index 7170fba..12e727e 100644
--- a/lndclient/chainnotifier_client.go
+++ b/lndclient/chainnotifier_client.go
@@ -7,7 +7,7 @@ import (
 
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/wire"
-	"github.com/lightninglabs/loop/utils"
+	"github.com/lightninglabs/loop/swap"
 	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/lnrpc/chainrpc"
 	"google.golang.org/grpc"
@@ -77,7 +77,7 @@ func (s *chainNotifierClient) RegisterSpendNtfn(ctx context.Context,
 		if err != nil {
 			return err
 		}
-		tx, err := utils.DecodeTx(d.RawSpendingTx)
+		tx, err := swap.DecodeTx(d.RawSpendingTx)
 		if err != nil {
 			return err
 		}
@@ -165,7 +165,7 @@ func (s *chainNotifierClient) RegisterConfirmationsNtfn(ctx context.Context,
 
 			// Script confirmed
 			case *chainrpc.ConfEvent_Conf:
-				tx, err := utils.DecodeTx(c.Conf.RawTx)
+				tx, err := swap.DecodeTx(c.Conf.RawTx)
 				if err != nil {
 					errChan <- err
 					return
diff --git a/lndclient/lnd_services.go b/lndclient/lnd_services.go
index f15591e..ab40949 100644
--- a/lndclient/lnd_services.go
+++ b/lndclient/lnd_services.go
@@ -4,13 +4,13 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"github.com/lightninglabs/loop/utils"
 	"io/ioutil"
 	"path/filepath"
 	"time"
 
 	"github.com/btcsuite/btcd/chaincfg"
 	"github.com/btcsuite/btcutil"
+	"github.com/lightninglabs/loop/swap"
 	"github.com/lightningnetwork/lnd/lncfg"
 	"github.com/lightningnetwork/lnd/macaroons"
 	"google.golang.org/grpc"
@@ -53,7 +53,7 @@ func NewLndServices(lndAddress string, application string,
 
 	logger.Infof("Connected to lnd")
 
-	chainParams, err := utils.ChainParamsFromNetwork(network)
+	chainParams, err := swap.ChainParamsFromNetwork(network)
 	if err != nil {
 		return nil, err
 	}
diff --git a/lndclient/signer_client.go b/lndclient/signer_client.go
index 5e7b5eb..e9397ba 100644
--- a/lndclient/signer_client.go
+++ b/lndclient/signer_client.go
@@ -4,7 +4,7 @@ import (
 	"context"
 
 	"github.com/btcsuite/btcd/wire"
-	"github.com/lightninglabs/loop/utils"
+	"github.com/lightninglabs/loop/swap"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/lnrpc/signrpc"
 	"google.golang.org/grpc"
@@ -29,7 +29,7 @@ func newSignerClient(conn *grpc.ClientConn) *signerClient {
 func (s *signerClient) SignOutputRaw(ctx context.Context, tx *wire.MsgTx,
 	signDescriptors []*input.SignDescriptor) ([][]byte, error) {
 
-	txRaw, err := utils.EncodeTx(tx)
+	txRaw, err := swap.EncodeTx(tx)
 	if err != nil {
 		return nil, err
 	}
diff --git a/lndclient/walletkit_client.go b/lndclient/walletkit_client.go
index ba506c8..a477978 100644
--- a/lndclient/walletkit_client.go
+++ b/lndclient/walletkit_client.go
@@ -6,7 +6,7 @@ import (
 	"github.com/btcsuite/btcd/btcec"
 	"github.com/btcsuite/btcd/wire"
 	"github.com/btcsuite/btcutil"
-	"github.com/lightninglabs/loop/utils"
+	"github.com/lightninglabs/loop/swap"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/lnrpc/signrpc"
 	"github.com/lightningnetwork/lnd/lnrpc/walletrpc"
@@ -117,7 +117,7 @@ func (m *walletKitClient) NextAddr(ctx context.Context) (
 func (m *walletKitClient) PublishTransaction(ctx context.Context,
 	tx *wire.MsgTx) error {
 
-	txHex, err := utils.EncodeTx(tx)
+	txHex, err := swap.EncodeTx(tx)
 	if err != nil {
 		return err
 	}
@@ -155,7 +155,7 @@ func (m *walletKitClient) SendOutputs(ctx context.Context,
 		return nil, err
 	}
 
-	tx, err := utils.DecodeTx(resp.RawTx)
+	tx, err := swap.DecodeTx(resp.RawTx)
 	if err != nil {
 		return nil, err
 	}
diff --git a/log.go b/log.go
new file mode 100644
index 0000000..3423dd5
--- /dev/null
+++ b/log.go
@@ -0,0 +1,70 @@
+package loop
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/btcsuite/btclog"
+	"github.com/lightningnetwork/lnd/lntypes"
+)
+
+// log is a logger that is initialized with no output filters.  This
+// means the package will not perform any logging by default until the caller
+// requests it.
+var (
+	backendLog     = btclog.NewBackend(logWriter{})
+	logger         = backendLog.Logger("CLIENT")
+	servicesLogger = backendLog.Logger("SERVICES")
+)
+
+// logWriter implements an io.Writer that outputs to both standard output and
+// the write-end pipe of an initialized log rotator.
+type logWriter struct{}
+
+func (logWriter) Write(p []byte) (n int, err error) {
+	os.Stdout.Write(p)
+	return len(p), nil
+}
+
+// SwapLog logs with a short swap hash prefix.
+type SwapLog struct {
+	// Logger is the underlying based logger.
+	Logger btclog.Logger
+
+	// Hash is the hash the identifies the target swap.
+	Hash lntypes.Hash
+}
+
+// Infof formats message according to format specifier and writes to
+// log with LevelInfo.
+func (s *SwapLog) Infof(format string, params ...interface{}) {
+	s.Logger.Infof(
+		fmt.Sprintf("%v %s", ShortHash(&s.Hash), format),
+		params...,
+	)
+}
+
+// Warnf formats message according to format specifier and writes to
+// to log with LevelError.
+func (s *SwapLog) Warnf(format string, params ...interface{}) {
+	s.Logger.Warnf(
+		fmt.Sprintf("%v %s", ShortHash(&s.Hash), format),
+		params...,
+	)
+}
+
+// Errorf formats message according to format specifier and writes to
+// to log with LevelError.
+func (s *SwapLog) Errorf(format string, params ...interface{}) {
+	s.Logger.Errorf(
+		fmt.Sprintf("%v %s", ShortHash(&s.Hash), format),
+		params...,
+	)
+
+}
+
+// ShortHash returns a shortened version of the hash suitable for use in
+// logging.
+func ShortHash(hash *lntypes.Hash) string {
+	return hash.String()[:6]
+}
diff --git a/client/server_mock_test.go b/server_mock_test.go
similarity index 99%
rename from client/server_mock_test.go
rename to server_mock_test.go
index eab38eb..28494bd 100644
--- a/client/server_mock_test.go
+++ b/server_mock_test.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"context"
diff --git a/client/store_mock_test.go b/store_mock_test.go
similarity index 99%
rename from client/store_mock_test.go
rename to store_mock_test.go
index 6c462a0..e492aa4 100644
--- a/client/store_mock_test.go
+++ b/store_mock_test.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"errors"
diff --git a/client/swap.go b/swap.go
similarity index 99%
rename from client/swap.go
rename to swap.go
index 63b098b..3b447bd 100644
--- a/client/swap.go
+++ b/swap.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"context"
diff --git a/client/swap_server_client.go b/swap_server_client.go
similarity index 99%
rename from client/swap_server_client.go
rename to swap_server_client.go
index 0e695f0..b005231 100644
--- a/client/swap_server_client.go
+++ b/swap_server_client.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"context"
diff --git a/test/lightning_client_mock.go b/test/lightning_client_mock.go
index 2d2ea83..e90a0f5 100644
--- a/test/lightning_client_mock.go
+++ b/test/lightning_client_mock.go
@@ -9,7 +9,7 @@ import (
 	"github.com/btcsuite/btcd/chaincfg"
 	"github.com/btcsuite/btcutil"
 	"github.com/lightninglabs/loop/lndclient"
-	"github.com/lightninglabs/loop/utils"
+	"github.com/lightninglabs/loop/swap"
 	"github.com/lightningnetwork/lnd/lnrpc/invoicesrpc"
 	"github.com/lightningnetwork/lnd/lntypes"
 	"github.com/lightningnetwork/lnd/lnwire"
@@ -34,7 +34,7 @@ func (h *mockLightningClient) PayInvoice(ctx context.Context, invoice string,
 	go func() {
 		defer h.wg.Done()
 
-		amt, err := utils.GetInvoiceAmt(&chaincfg.TestNet3Params, invoice)
+		amt, err := swap.GetInvoiceAmt(&chaincfg.TestNet3Params, invoice)
 		if err != nil {
 			select {
 			case done <- lndclient.PaymentResult{
diff --git a/client/testcontext_test.go b/testcontext_test.go
similarity index 95%
rename from client/testcontext_test.go
rename to testcontext_test.go
index d13260a..45e95d2 100644
--- a/client/testcontext_test.go
+++ b/testcontext_test.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"context"
@@ -139,8 +139,9 @@ func (ctx *testContext) finish() {
 	ctx.assertIsDone()
 }
 
-// notifyHeight notifies swap client of the arrival of a new block and waits for
-// the notification to be processed by selecting on a dedicated test channel.
+// notifyHeight notifies swap client of the arrival of a new block and
+// waits for the notification to be processed by selecting on a dedicated
+// test channel.
 func (ctx *testContext) notifyHeight(height int32) {
 	ctx.T.Helper()
 
@@ -205,7 +206,9 @@ func (ctx *testContext) assertStatus(expectedState SwapState) {
 	}
 }
 
-func (ctx *testContext) publishHtlc(script []byte, amt btcutil.Amount) wire.OutPoint {
+func (ctx *testContext) publishHtlc(script []byte,
+	amt btcutil.Amount) wire.OutPoint {
+
 	// Create the htlc tx.
 	htlcTx := wire.MsgTx{}
 	htlcTx.AddTxIn(&wire.TxIn{
diff --git a/client/uncharge.go b/uncharge.go
similarity index 99%
rename from client/uncharge.go
rename to uncharge.go
index c55d7e7..66cabc0 100644
--- a/client/uncharge.go
+++ b/uncharge.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"context"
@@ -305,10 +305,9 @@ func (s *unchargeSwap) executeSwap(globalCtx context.Context) error {
 		return err
 	}
 
-	// Inspect witness stack to see if it is a success transaction. We don't
-	// just try to match with the hash of our sweep tx, because it may be
-	// swept by a different (fee) sweep tx from a previous run.
-
+	// Inspect witness stack to see if it is a success transaction. We
+	// don't just try to match with the hash of our sweep tx, because it
+	// may be swept by a different (fee) sweep tx from a previous run.
 	htlcInput, err := getTxInputByOutpoint(
 		spendDetails.SpendingTx, htlcOutpoint,
 	)
diff --git a/uncharge_state.go b/uncharge_state.go
new file mode 100644
index 0000000..2d09be7
--- /dev/null
+++ b/uncharge_state.go
@@ -0,0 +1 @@
+package loop
diff --git a/client/uncharge_test.go b/uncharge_test.go
similarity index 99%
rename from client/uncharge_test.go
rename to uncharge_test.go
index 6cd6753..29b8f49 100644
--- a/client/uncharge_test.go
+++ b/uncharge_test.go
@@ -1,4 +1,4 @@
-package client
+package loop
 
 import (
 	"context"