feat(xrpl): AuthorizeChannel to authorize a payment channel.

Author: JordiParraCrespo

CHANGELOG.md

@@ -7,8 +7,16 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+#### xrpl
+
+- `AuthorizeChannel` to authorize a payment channel.
+
 ### Refactored
 
+#### xrpl
+
 - `TxResponse` `Meta` field type changed to `TxMetadataBuilder`, enabling custom parsing for specific transactions metadata such as `Payment`, `NFTokenMint`, etc.
 
 ## [v0.1.13]

xrpl/wallet/authorize_channel.go

@@ -0,0 +1,34 @@
+package wallet
+
+import (
+	"encoding/hex"
+
+	binarycodec "github.com/Peersyst/xrpl-go/binary-codec"
+	"github.com/Peersyst/xrpl-go/keypairs"
+)
+
+// AuthorizeChannel returns a signature authorizing the redemption of a specific
+// amount of XRP from a payment channel.
+//
+// channelID identifies the payment channel.
+// amount is the amount to redeem, expressed in drops.
+//
+// Returns the signature or an error if the signature cannot be created.
+func AuthorizeChannel(channelID, amount string, wallet *Wallet) (string, error) {
+	encodedData, err := binarycodec.EncodeForSigningClaim(map[string]any{
+		"Channel": channelID,
+		"Amount":  amount,
+	})
+	if err != nil {
+		return "", err
+	}
+	hexData, err := hex.DecodeString(encodedData)
+	if err != nil {
+		return "", err
+	}
+	signedData, err := keypairs.Sign(string(hexData), wallet.PrivateKey)
+	if err != nil {
+		return "", err
+	}
+	return signedData, nil
+}

xrpl/wallet/authorize_channel_test.go

@@ -0,0 +1,161 @@
+package wallet
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestAuthorizeChannel(t *testing.T) {
+	// secp256k1 wallet
+	secpWallet, err := FromSeed("snGHNrPbHrdUcszeuDEigMdC1Lyyd", "")
+	require.NoError(t, err)
+
+	// ed25519 wallet
+	edWallet, err := FromSeed("sEdSuqBPSQaood2DmNYVkwWTn1oQTj2", "")
+	require.NoError(t, err)
+
+	channelID := "5DB01B7FFED6B67E6B0414DED11E051D2EE2B7619CE0EAA6286D67A3A4D5BDB3"
+	amount := "1000000"
+
+	tc := []struct {
+		name        string
+		wallet      *Wallet
+		channelID   string
+		amount      string
+		expectedSig string
+	}{
+		{
+			name:        "pass - succeeds with secp256k1 seed",
+			wallet:      &secpWallet,
+			channelID:   channelID,
+			amount:      amount,
+			expectedSig: "304402204E7052F33DDAFAAA55C9F5B132A5E50EE95B2CF68C0902F61DFE77299BC893740220353640B951DCD24371C16868B3F91B78D38B6F3FD1E826413CDF891FA8250AAC",
+		},
+		{
+			name:        "pass - succeeds with ed25519 seed",
+			wallet:      &edWallet,
+			channelID:   channelID,
+			amount:      amount,
+			expectedSig: "7E1C217A3E4B3C107B7A356E665088B4FBA6464C48C58267BEF64975E3375EA338AE22E6714E3F5E734AE33E6B97AAD59058E1E196C1F92346FC1498D0674404",
+		},
+		{
+			name:        "fail - fails with invalid channel ID format",
+			wallet:      &secpWallet,
+			channelID:   "invalid-id",
+			amount:      amount,
+			expectedSig: "",
+		},
+		{
+			name:        "fail - fails with invalid amount format",
+			wallet:      &secpWallet,
+			channelID:   channelID,
+			amount:      "invalid-amount",
+			expectedSig: "",
+		},
+	}
+
+	for _, tt := range tc {
+		t.Run(tt.name, func(t *testing.T) {
+			signature, err := AuthorizeChannel(tt.channelID, tt.amount, tt.wallet)
+			if err == nil && tt.expectedSig != "" {
+				require.NoError(t, err)
+				require.Equal(t, tt.expectedSig, signature)
+			} else {
+				require.Error(t, err)
+				require.Empty(t, signature)
+			}
+		})
+	}
+}
+
+func TestAuthorizeChannel_EdgeCases(t *testing.T) {
+	// secp256k1 wallet
+	secpWallet, err := FromSeed("snGHNrPbHrdUcszeuDEigMdC1Lyyd", "")
+	require.NoError(t, err)
+
+	// ed25519 wallet
+	edWallet, err := FromSeed("sEdSuqBPSQaood2DmNYVkwWTn1oQTj2", "")
+	require.NoError(t, err)
+
+	validChannelID := "5DB01B7FFED6B67E6B0414DED11E051D2EE2B7619CE0EAA6286D67A3A4D5BDB3"
+	validAmount := "1000000"
+
+	tc := []struct {
+		name        string
+		wallet      *Wallet
+		channelID   string
+		amount      string
+		expectError bool
+	}{
+		{
+			name:        "pass - different amounts with secp256k1",
+			wallet:      &secpWallet,
+			channelID:   validChannelID,
+			amount:      "5000000",
+			expectError: false,
+		},
+		{
+			name:        "pass - different amounts with ed25519",
+			wallet:      &edWallet,
+			channelID:   validChannelID,
+			amount:      "5000000",
+			expectError: false,
+		},
+		{
+			name:        "pass - zero amount",
+			wallet:      &secpWallet,
+			channelID:   validChannelID,
+			amount:      "0",
+			expectError: false,
+		},
+		{
+			name:        "fail - empty channel ID",
+			wallet:      &secpWallet,
+			channelID:   "",
+			amount:      validAmount,
+			expectError: true,
+		},
+		{
+			name:        "fail - empty amount",
+			wallet:      &secpWallet,
+			channelID:   validChannelID,
+			amount:      "",
+			expectError: true,
+		},
+		{
+			name:        "fail - channel ID too short",
+			wallet:      &secpWallet,
+			channelID:   "5DB01B7FFED6B67E6B0414DED11E051D2EE2B7619CE0EAA6286D67A3A4D5BDB",
+			amount:      validAmount,
+			expectError: true,
+		},
+		{
+			name:        "fail - channel ID too long",
+			wallet:      &secpWallet,
+			channelID:   "5DB01B7FFED6B67E6B0414DED11E051D2EE2B7619CE0EAA6286D67A3A4D5BDB3A",
+			amount:      validAmount,
+			expectError: true,
+		},
+		{
+			name:        "fail - channel ID with invalid hex characters",
+			wallet:      &secpWallet,
+			channelID:   "5DB01B7FFED6B67E6B0414DED11E051D2EE2B7619CE0EAA6286D67A3A4D5BDBG",
+			amount:      validAmount,
+			expectError: true,
+		},
+	}
+
+	for _, tt := range tc {
+		t.Run(tt.name, func(t *testing.T) {
+			signature, err := AuthorizeChannel(tt.channelID, tt.amount, tt.wallet)
+			if tt.expectError {
+				require.Error(t, err)
+				require.Empty(t, signature)
+			} else {
+				require.NoError(t, err)
+				require.NotEmpty(t, signature)
+			}
+		})
+	}
+}