From 08a3da44b100c86b71a41fbd33d23abb26b7a646 Mon Sep 17 00:00:00 2001
From: Aaron Craelius <aaronc@users.noreply.github.com>
Date: Tue, 20 Aug 2024 11:01:29 -0400
Subject: [PATCH] feat(schema/indexer): add address codec param (#21361)

---
 schema/addressutil/codec.go    |  8 +++++
 schema/addressutil/hex.go      | 24 +++++++++++++++
 schema/addressutil/hex_test.go | 54 ++++++++++++++++++++++++++++++++++
 schema/indexer/indexer.go      |  5 ++++
 schema/indexer/manager.go      |  6 ++++
 5 files changed, 97 insertions(+)
 create mode 100644 schema/addressutil/codec.go
 create mode 100644 schema/addressutil/hex.go
 create mode 100644 schema/addressutil/hex_test.go

diff --git a/schema/addressutil/codec.go b/schema/addressutil/codec.go
new file mode 100644
index 000000000000..cadde8e516cd
--- /dev/null
+++ b/schema/addressutil/codec.go
@@ -0,0 +1,8 @@
+package addressutil
+
+type AddressCodec interface {
+	// StringToBytes decodes text to bytes
+	StringToBytes(text string) ([]byte, error)
+	// BytesToString encodes bytes to text
+	BytesToString(bz []byte) (string, error)
+}
diff --git a/schema/addressutil/hex.go b/schema/addressutil/hex.go
new file mode 100644
index 000000000000..1d6ecae467ce
--- /dev/null
+++ b/schema/addressutil/hex.go
@@ -0,0 +1,24 @@
+package addressutil
+
+import (
+	"encoding/hex"
+	"fmt"
+)
+
+// HexAddressCodec is a basic address codec that encodes and decodes addresses as hex strings.
+// It is intended to be used as a fallback codec when no other codec is provided.
+type HexAddressCodec struct{}
+
+func (h HexAddressCodec) StringToBytes(text string) ([]byte, error) {
+	if len(text) < 2 || text[:2] != "0x" {
+		return nil, fmt.Errorf("invalid hex address: %s", text)
+	}
+
+	return hex.DecodeString(text[2:])
+}
+
+func (h HexAddressCodec) BytesToString(bz []byte) (string, error) {
+	return fmt.Sprintf("0x%x", bz), nil
+}
+
+var _ AddressCodec = HexAddressCodec{}
diff --git a/schema/addressutil/hex_test.go b/schema/addressutil/hex_test.go
new file mode 100644
index 000000000000..e4a0f0ee01f9
--- /dev/null
+++ b/schema/addressutil/hex_test.go
@@ -0,0 +1,54 @@
+package addressutil
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestHexAddressCodec(t *testing.T) {
+	tt := []struct {
+		text string
+		bz   []byte
+		err  bool
+	}{
+		{
+			text: "0x1234",
+			bz:   []byte{0x12, 0x34},
+		},
+		{
+			text: "0x",
+			bz:   []byte{},
+		},
+		{
+			text: "0x123",
+			err:  true,
+		},
+		{
+			text: "1234",
+			err:  true,
+		},
+	}
+
+	h := HexAddressCodec{}
+	for _, tc := range tt {
+		bz, err := h.StringToBytes(tc.text)
+		if tc.err && err == nil {
+			t.Fatalf("expected error, got none")
+		}
+		if !tc.err && err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if !tc.err && !bytes.Equal(bz, tc.bz) {
+			t.Fatalf("expected %v, got %v", tc.bz, bz)
+		}
+
+		// check address rendering if no error
+		if !tc.err {
+			if str, err := h.BytesToString(tc.bz); err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			} else if str != tc.text {
+				t.Fatalf("expected %s, got %s", tc.text, str)
+			}
+		}
+	}
+}
diff --git a/schema/indexer/indexer.go b/schema/indexer/indexer.go
index 57ada8bb80c1..3b82e3254e5a 100644
--- a/schema/indexer/indexer.go
+++ b/schema/indexer/indexer.go
@@ -3,6 +3,7 @@ package indexer
 import (
 	"context"
 
+	"cosmossdk.io/schema/addressutil"
 	"cosmossdk.io/schema/appdata"
 	"cosmossdk.io/schema/logutil"
 	"cosmossdk.io/schema/view"
@@ -62,6 +63,10 @@ type InitParams struct {
 	// Logger is a logger the indexer can use to write log messages. It may be nil if the indexer does not need
 	// to write logs.
 	Logger logutil.Logger
+
+	// AddressCodec is the address codec that the indexer can use to encode and decode addresses. It is
+	// expected to be non-nil.
+	AddressCodec addressutil.AddressCodec
 }
 
 // InitResult is the indexer initialization result and includes the indexer's listener implementation.
diff --git a/schema/indexer/manager.go b/schema/indexer/manager.go
index 5a7e39faad0a..60c19b4dd5c7 100644
--- a/schema/indexer/manager.go
+++ b/schema/indexer/manager.go
@@ -3,6 +3,7 @@ package indexer
 import (
 	"context"
 
+	"cosmossdk.io/schema/addressutil"
 	"cosmossdk.io/schema/appdata"
 	"cosmossdk.io/schema/decoding"
 	"cosmossdk.io/schema/logutil"
@@ -29,6 +30,11 @@ type ManagerOptions struct {
 	// be used to pass down other parameters to indexers if necessary. If it is omitted, context.Background
 	// will be used.
 	Context context.Context
+
+	// AddressCodec is the address codec that indexers can use to encode and decode addresses. It should always be
+	// provided, but if it is omitted, the indexer manager will use a default codec which encodes and decodes addresses
+	// as hex strings.
+	AddressCodec addressutil.AddressCodec
 }
 
 // ManagerConfig is the configuration of the indexer manager and contains the configuration for each indexer target.