From 1ee8d7518c9a0d13554c83ea9c92fa23a37e4c63 Mon Sep 17 00:00:00 2001
From: Wilmer Paulino <wilmer.paulino@gmail.com>
Date: Thu, 6 Dec 2018 21:14:02 -0800
Subject: [PATCH] chainntnfs/btcdnotify: add chainParams parameter to
 btcdnotify.New

In this commit, we add the current chain parameters to the BtcdNotifier.
This will be used in a future commit in order to convert outputs scripts
into addresses. This is needed since the btcd backend uses these
addresses to detect whether the script encoded within it was spent by a
transaction in the chain.
---
 chainntnfs/btcdnotify/btcd.go      |  9 +++++++--
 chainntnfs/btcdnotify/btcd_test.go |  2 +-
 chainntnfs/btcdnotify/driver.go    | 23 +++++++++++++++--------
 3 files changed, 23 insertions(+), 11 deletions(-)

diff --git a/chainntnfs/btcdnotify/btcd.go b/chainntnfs/btcdnotify/btcd.go
index 4e900608..4d83ae62 100644
--- a/chainntnfs/btcdnotify/btcd.go
+++ b/chainntnfs/btcdnotify/btcd.go
@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"github.com/btcsuite/btcd/btcjson"
+	"github.com/btcsuite/btcd/chaincfg"
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/rpcclient"
 	"github.com/btcsuite/btcd/wire"
@@ -64,7 +65,8 @@ type BtcdNotifier struct {
 	started int32 // To be used atomically.
 	stopped int32 // To be used atomically.
 
-	chainConn *rpcclient.Client
+	chainConn   *rpcclient.Client
+	chainParams *chaincfg.Params
 
 	notificationCancels  chan interface{}
 	notificationRegistry chan interface{}
@@ -98,10 +100,13 @@ var _ chainntnfs.ChainNotifier = (*BtcdNotifier)(nil)
 // New returns a new BtcdNotifier instance. This function assumes the btcd node
 // detailed in the passed configuration is already running, and willing to
 // accept new websockets clients.
-func New(config *rpcclient.ConnConfig, spendHintCache chainntnfs.SpendHintCache,
+func New(config *rpcclient.ConnConfig, chainParams *chaincfg.Params,
+	spendHintCache chainntnfs.SpendHintCache,
 	confirmHintCache chainntnfs.ConfirmHintCache) (*BtcdNotifier, error) {
 
 	notifier := &BtcdNotifier{
+		chainParams: chainParams,
+
 		notificationCancels:  make(chan interface{}),
 		notificationRegistry: make(chan interface{}),
 
diff --git a/chainntnfs/btcdnotify/btcd_test.go b/chainntnfs/btcdnotify/btcd_test.go
index 18bd1bb3..f76f9b94 100644
--- a/chainntnfs/btcdnotify/btcd_test.go
+++ b/chainntnfs/btcdnotify/btcd_test.go
@@ -37,7 +37,7 @@ func setUpNotifier(t *testing.T, h *rpctest.Harness) *BtcdNotifier {
 	hintCache := initHintCache(t)
 
 	rpcCfg := h.RPCConfig()
-	notifier, err := New(&rpcCfg, hintCache, hintCache)
+	notifier, err := New(&rpcCfg, chainntnfs.NetParams, hintCache, hintCache)
 	if err != nil {
 		t.Fatalf("unable to create notifier: %v", err)
 	}
diff --git a/chainntnfs/btcdnotify/driver.go b/chainntnfs/btcdnotify/driver.go
index 1cda9192..901426f2 100644
--- a/chainntnfs/btcdnotify/driver.go
+++ b/chainntnfs/btcdnotify/driver.go
@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 
+	"github.com/btcsuite/btcd/chaincfg"
 	"github.com/btcsuite/btcd/rpcclient"
 	"github.com/lightningnetwork/lnd/chainntnfs"
 )
@@ -11,30 +12,36 @@ import (
 // createNewNotifier creates a new instance of the ChainNotifier interface
 // implemented by BtcdNotifier.
 func createNewNotifier(args ...interface{}) (chainntnfs.ChainNotifier, error) {
-	if len(args) != 3 {
+	if len(args) != 4 {
 		return nil, fmt.Errorf("incorrect number of arguments to "+
-			".New(...), expected 2, instead passed %v", len(args))
+			".New(...), expected 4, instead passed %v", len(args))
 	}
 
 	config, ok := args[0].(*rpcclient.ConnConfig)
 	if !ok {
-		return nil, errors.New("first argument to btcdnotifier.New " +
+		return nil, errors.New("first argument to btcdnotify.New " +
 			"is incorrect, expected a *rpcclient.ConnConfig")
 	}
 
-	spendHintCache, ok := args[1].(chainntnfs.SpendHintCache)
+	chainParams, ok := args[1].(*chaincfg.Params)
 	if !ok {
-		return nil, errors.New("second argument to btcdnotifier.New " +
+		return nil, errors.New("second argument to btcdnotify.New " +
+			"is incorrect, expected a *chaincfg.Params")
+	}
+
+	spendHintCache, ok := args[2].(chainntnfs.SpendHintCache)
+	if !ok {
+		return nil, errors.New("third argument to btcdnotify.New " +
 			"is incorrect, expected a chainntnfs.SpendHintCache")
 	}
 
-	confirmHintCache, ok := args[2].(chainntnfs.ConfirmHintCache)
+	confirmHintCache, ok := args[3].(chainntnfs.ConfirmHintCache)
 	if !ok {
-		return nil, errors.New("third argument to btcdnotifier.New " +
+		return nil, errors.New("fourth argument to btcdnotify.New " +
 			"is incorrect, expected a chainntnfs.ConfirmHintCache")
 	}
 
-	return New(config, spendHintCache, confirmHintCache)
+	return New(config, chainParams, spendHintCache, confirmHintCache)
 }
 
 // init registers a driver for the BtcdNotifier concrete implementation of the