* refactor(channel/AdjEventSub): Set AdjEventSub to adhere to Adjudic…

…atorSubscription in go-perun. In run method, do not return if adjEvent is found.

* refactor(channel/subscribe.go): Add IMPORTANT fix: In the DifferencesInControls function, if current state and next state are both Closed in the payment contract, then return a CloseEvent. This  triggers a ConcludedEvent in Next(). This fix removes potential problems in edge cases in which the contract is closed, but no event was caught. This could have blocked the conclusion of the channel. The added code prevents such cases and guarantees that a closed channel in the contract is always detected.
Rename variables in Next() to be more descriptive.

* test(channel_test): Add client_test.go, testing the go-perun client functionality with the payment channel workflow.

* refactor(channel/test): Add wallet.EphemeralWallet as return value in MakeRandPerunAccWallet(), satisfying requirements in the client_test.go test. Improve file path parsing, using getDataFilePath.

* refactor(event): Rename PerunEvent methods to adhere to AdjudicatorEvent interface from go-perun.

*add(payment): Add payment package to include test infrastructure for the go-perun client, used by client_test.go.

channel/adjudicator_sub.go

@@ -32,7 +32,6 @@ const (
 	DefaultSubscriptionPollingInterval = time.Duration(5) * time.Second
 )
 
-// AdjudicatorSub implements the AdjudicatorSubscription interface.
 type AdjEventSub struct {
 	challengeDuration *time.Duration
 	stellarClient     *client.Client
@@ -49,7 +48,7 @@ type AdjEventSub struct {
 	log               log.Embedding
 }
 
-func NewAdjudicatorSub(ctx context.Context, cid pchannel.ID, stellarClient *client.Client, perunAddr xdr.ScAddress, assetAddr xdr.ScAddress, challengeDuration *time.Duration) (*AdjEventSub, error) {
+func NewAdjudicatorSub(ctx context.Context, cid pchannel.ID, stellarClient *client.Client, perunAddr xdr.ScAddress, assetAddr xdr.ScAddress, challengeDuration *time.Duration) (pchannel.AdjudicatorSubscription, error) {
 
 	sub := &AdjEventSub{
 		challengeDuration: challengeDuration,
@@ -92,15 +91,14 @@ polling:
 			finish(err)
 			return
 		case <-ctx.Done():
+			s.log.Log().Debug("Timeout during Adjudicator Subscription")
 			finish(nil)
 			return
 		case <-time.After(s.pollInterval):
-
-			newChanInfo, err := s.stellarClient.GetChannelInfo(ctx, s.perunAddr, s.cid) // getChanControl()
+			newChanInfo, err := s.stellarClient.GetChannelInfo(ctx, s.perunAddr, s.cid)
 			newChanControl = newChanInfo.Control
 
 			if err != nil {
-
 				s.subErrors <- err
 			}
 			adjEvent, err := DifferencesInControls(s.chanControl, newChanControl)
@@ -117,7 +115,6 @@ polling:
 				s.log.Log().Debug("Contract event detected, evaluating...")
 				s.log.Log().Debugf("Found contract event: %v", adjEvent)
 				s.events <- adjEvent
-				return
 			}
 		}
 	}
@@ -129,9 +126,6 @@ func DifferencesInControls(controlCurr, controlNext wire.Control) (event.PerunEv
 		if controlCurr.FundedA {
 			return nil, errors.New("channel cannot be unfunded A before withdrawal")
 		}
-		if controlNext.WithdrawnA && controlNext.WithdrawnB {
-			return &event.FundEvent{}, nil
-		}
 	}
 
 	if controlCurr.FundedB != controlNext.FundedB {
@@ -153,6 +147,10 @@ func DifferencesInControls(controlCurr, controlNext wire.Control) (event.PerunEv
 		return &event.CloseEvent{}, nil
 	}
 
+	if controlCurr.Closed && controlNext.Closed {
+		return &event.CloseEvent{}, nil
+	}
+
 	if controlCurr.WithdrawnA != controlNext.WithdrawnA {
 		if controlCurr.WithdrawnA {
 			return nil, errors.New("channel cannot be unwithdrawn")

channel/adjudicator_test.go

@@ -81,16 +81,21 @@ func TestHappyChannel(t *testing.T) {
 			Idx:       pchannel.Index(1),
 			Secondary: false}
 
+		_, err = adjAlice.Subscribe(ctx, next.ID)
+		require.NoError(t, err)
 		require.NoError(t, adjAlice.Withdraw(ctxAliceWithdraw, reqAlice, nil))
+		// ev := subAlice.Next()
+		// if _, ok := ev.(pchannel.ConcludedEvent); ok {
+		// 	fmt.Println("event concluded is here")
+		// }
+
 		perunAddrAlice := adjAlice.GetPerunAddr()
 		stellarChanAlice, err := adjAlice.StellarClient.GetChannelInfo(ctx, perunAddrAlice, next.ID)
-
 		require.True(t, stellarChanAlice.Control.WithdrawnA)
 
 		require.NoError(t, err)
 		require.NoError(t, adjBob.Withdraw(ctx, reqBob, nil))
 		perunAddrBob := adjBob.GetPerunAddr()
-
 		stellarChanBob, err := adjBob.StellarClient.GetChannelInfo(ctxBobWithdraw, perunAddrBob, next.ID)
 
 		require.NoError(t, err)

channel/funder.go

@@ -82,6 +82,7 @@ func (f *Funder) fundParty(ctx context.Context, req pchannel.FundingReq) error {
 		case <-ctx.Done():
 			timeoutErr := makeTimeoutErr([]pchannel.Index{req.Idx}, 0)
 			errAbort := f.AbortChannel(ctx, req.State)
+			log.Printf("%s: Aborting channel due to timeout...\n", party)
 			if errAbort != nil {
 				return errAbort
 			}

channel/subscribe.go

@@ -29,7 +29,6 @@ func (s *AdjEventSub) Next() pchannel.AdjudicatorEvent {
 	if s.getEvents() == nil {
 		return nil
 	}
-
 	select {
 	case ev := <-s.getEvents():
 		if ev == nil {
@@ -38,27 +37,26 @@ func (s *AdjEventSub) Next() pchannel.AdjudicatorEvent {
 
 		switch e := ev.(type) {
 		case *event.DisputedEvent:
-			log.Println("DisputedEvent received")
+			log.Println("DisputedEvent received - build RegisteredEvent")
 			dispEvent := pchannel.AdjudicatorEventBase{
-				VersionV: e.GetVersion(),
-				IDV:      e.GetID(),
+				VersionV: e.Version(),
+				IDV:      e.ID(),
 				TimeoutV: event.MakeTimeout(*s.challengeDuration),
 			}
-			ddn := &pchannel.RegisteredEvent{AdjudicatorEventBase: dispEvent, State: nil, Sigs: nil}
-			s.closer.Close()
-			return ddn
+			adjDispEvent := &pchannel.RegisteredEvent{AdjudicatorEventBase: dispEvent, State: nil, Sigs: nil}
+			return adjDispEvent
 
 		case *event.CloseEvent:
 
-			log.Println("CloseEvent received")
+			log.Println("CloseEvent received - build ConcludedEvent")
+
 			conclEvent := pchannel.AdjudicatorEventBase{
-				VersionV: e.GetVersion(),
-				IDV:      e.GetID(),
+				VersionV: e.Version(),
+				IDV:      e.ID(),
 				TimeoutV: event.MakeTimeout(*s.challengeDuration),
 			}
-			ccn := &pchannel.ConcludedEvent{AdjudicatorEventBase: conclEvent}
-			s.closer.Close()
-			return ccn
+			adjConclEvent := &pchannel.ConcludedEvent{AdjudicatorEventBase: conclEvent}
+			return adjConclEvent
 
 		default:
 			log.Printf("Received an unknown event type: %v\n", reflect.TypeOf(e))

channel/test/setup.go

@@ -1,4 +1,4 @@
-// Copyright 2023 PolyCrypt GmbH
+// Copyright 2024 PolyCrypt GmbH
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -26,6 +26,7 @@ import (
 	"log"
 	"math/big"
 	mathrand "math/rand"
+	"path/filepath"
 	pchannel "perun.network/go-perun/channel"
 	ptest "perun.network/go-perun/channel/test"
 	pwallet "perun.network/go-perun/wallet"
@@ -34,21 +35,23 @@ import (
 	"perun.network/perun-stellar-backend/client"
 	"perun.network/perun-stellar-backend/wallet"
 	pkgtest "polycry.pt/poly-go/test"
+	"runtime"
 	"testing"
 	"time"
 )
 
 const (
-	PerunContractPath        = "../testdata/perun_soroban_contract.wasm"
-	StellarAssetContractPath = "../testdata/perun_soroban_token.wasm"
+	PerunContractPath        = "testdata/perun_soroban_contract.wasm"
+	StellarAssetContractPath = "testdata/perun_soroban_token.wasm"
 	initLumensBalance        = "10000000"
 	initTokenBalance         = uint64(2000000)
-	DefaultTestTimeout       = 20
+	DefaultTestTimeout       = 30
 )
 
 type Setup struct {
 	t              *testing.T
 	accs           []*wallet.Account
+	ws             []*wallet.EphemeralWallet
 	stellarClients []*client.Client
 	Rng            *mathrand.Rand
 	funders        []*channel.Funder
@@ -76,36 +79,68 @@ func (s *Setup) GetAccounts() []*wallet.Account {
 	return s.accs
 }
 
+func (s *Setup) GetWallets() []*wallet.EphemeralWallet {
+	return s.ws
+}
+
+func getProjectRoot() (string, error) {
+	_, b, _, _ := runtime.Caller(1)
+	basepath := filepath.Dir(b)
+
+	fp, err := filepath.Abs(filepath.Join(basepath, "../..")) //filepath.Abs(filepath.Join(basepath, "../.."))
+	return fp, err
+}
+
+func getDataFilePath(filename string) (string, error) {
+	root, err := getProjectRoot()
+	if err != nil {
+		return "", err
+	}
+
+	fp := filepath.Join(root, "", filename) //filepath.Join(root, "testdata", filename)
+	return fp, nil
+}
+
 func NewTestSetup(t *testing.T) *Setup {
 
-	accs, kpsToFund := MakeRandPerunAccs(4)
+	accs, kpsToFund, ws := MakeRandPerunAccsWallets(4)
 	require.NoError(t, CreateFundStellarAccounts(kpsToFund, initLumensBalance))
 
 	depTokenKp := kpsToFund[2]
 	depPerunKp := kpsToFund[3]
 
-	tokenAddress, _ := Deploy(t, depTokenKp, StellarAssetContractPath)
-	perunAddress, _ := Deploy(t, depPerunKp, PerunContractPath)
+	relPathPerun, err := getDataFilePath(PerunContractPath)
+	require.NoError(t, err)
+	relPathAsset, err := getDataFilePath(StellarAssetContractPath)
+	require.NoError(t, err)
+
+	tokenAddress, _ := Deploy(t, depTokenKp, relPathAsset)
+	perunAddress, _ := Deploy(t, depPerunKp, relPathPerun)
 
 	require.NoError(t, InitTokenContract(depTokenKp, tokenAddress))
 
-	setupAccountsAndContracts(t, depTokenKp, kpsToFund[:2], tokenAddress, initTokenBalance)
+	SetupAccountsAndContracts(t, depTokenKp, kpsToFund[:2], tokenAddress, initTokenBalance)
 
 	assetContractID, err := types.NewStellarAssetFromScAddress(tokenAddress)
 	require.NoError(t, err)
 
 	stellarClients := NewStellarClients(kpsToFund)
 
 	aliceClient := stellarClients[0]
+	aliceWallet := ws[0]
 	bobClient := stellarClients[1]
+	bobWallet := ws[1]
+
 	channelAccs := []*wallet.Account{accs[0], accs[1]}
 	channelClients := []*client.Client{aliceClient, bobClient}
+	channelWallets := []*wallet.EphemeralWallet{aliceWallet, bobWallet}
 
-	funders, adjs := createFundersAndAdjudicators(channelAccs, stellarClients, perunAddress, tokenAddress)
+	funders, adjs := CreateFundersAndAdjudicators(channelAccs, stellarClients, perunAddress, tokenAddress)
 
 	setup := Setup{
 		t:              t,
 		accs:           channelAccs,
+		ws:             channelWallets,
 		stellarClients: channelClients,
 		funders:        funders,
 		adjs:           adjs,
@@ -115,15 +150,15 @@ func NewTestSetup(t *testing.T) *Setup {
 	return &setup
 }
 
-func setupAccountsAndContracts(t *testing.T, deployerKp *keypair.Full, kps []*keypair.Full, tokenAddress xdr.ScAddress, tokenBalance uint64) {
+func SetupAccountsAndContracts(t *testing.T, deployerKp *keypair.Full, kps []*keypair.Full, tokenAddress xdr.ScAddress, tokenBalance uint64) {
 	for _, kp := range kps {
 		addr, err := types.MakeAccountAddress(kp)
 		require.NoError(t, err)
 		require.NoError(t, MintToken(deployerKp, tokenAddress, tokenBalance, addr))
 	}
 }
 
-func createFundersAndAdjudicators(accs []*wallet.Account, clients []*client.Client, perunAddress, tokenAddress xdr.ScAddress) ([]*channel.Funder, []*channel.Adjudicator) {
+func CreateFundersAndAdjudicators(accs []*wallet.Account, clients []*client.Client, perunAddress, tokenAddress xdr.ScAddress) ([]*channel.Funder, []*channel.Adjudicator) {
 	funders := make([]*channel.Funder, len(accs))
 	adjs := make([]*channel.Adjudicator, len(accs))
 	for i, acc := range accs {
@@ -141,16 +176,18 @@ func NewStellarClients(kps []*keypair.Full) []*client.Client {
 	return clients
 }
 
-func MakeRandPerunAccs(count int) ([]*wallet.Account, []*keypair.Full) {
+func MakeRandPerunAccsWallets(count int) ([]*wallet.Account, []*keypair.Full, []*wallet.EphemeralWallet) {
 	accs := make([]*wallet.Account, count)
 	kps := make([]*keypair.Full, count)
+	ws := make([]*wallet.EphemeralWallet, count)
 
 	for i := 0; i < count; i++ {
-		acc, kp := MakeRandPerunAcc()
+		acc, kp, w := MakeRandPerunAccWallet()
 		accs[i] = acc
 		kps[i] = kp
+		ws[i] = w
 	}
-	return accs, kps
+	return accs, kps, ws
 }
 
 func MakeRandPerunAcc() (*wallet.Account, *keypair.Full) {
@@ -173,6 +210,26 @@ func MakeRandPerunAcc() (*wallet.Account, *keypair.Full) {
 	return acc, kp
 }
 
+func MakeRandPerunAccWallet() (*wallet.Account, *keypair.Full, *wallet.EphemeralWallet) {
+	w := wallet.NewEphemeralWallet()
+
+	var b [8]byte
+	_, err := rand.Read(b[:])
+	if err != nil {
+		panic(err)
+	}
+
+	seed := binary.LittleEndian.Uint64(b[:])
+
+	r := mathrand.New(mathrand.NewSource(int64(seed)))
+
+	acc, kp, err := w.AddNewAccount(r)
+	if err != nil {
+		panic(err)
+	}
+	return acc, kp, w
+}
+
 func CreateFundStellarAccounts(pairs []*keypair.Full, initialBalance string) error {
 
 	numKps := len(pairs)
@@ -230,7 +287,7 @@ func CreateFundStellarAccounts(pairs []*keypair.Full, initialBalance string) err
 	}
 
 	for _, keys := range pairs {
-		log.Printf("Funded %s (%s) with %s XLM.\n",
+		log.Printf("Funded Stellar L1 account %s (%s) with %s XLM.\n",
 			keys.Seed(), keys.Address(), initialBalance)
 	}