chore: import upstream snapshot with attribution

internal/binding/json_pointer.go

@@ -0,0 +1,80 @@
+// Copyright (c) 2026 Lark Technologies Pte. Ltd.
+// SPDX-License-Identifier: MIT
+
+package binding
+
+import (
+	"fmt"
+	"strings"
+)
+
+// ReadJSONPointer navigates a parsed JSON value (typically the result of
+// json.Unmarshal into interface{}) using an RFC 6901 JSON Pointer string.
+//
+// Supported pointer format: "/key/subkey/subsubkey".
+// An empty pointer ("") returns data as-is.
+// RFC 6901 escape sequences: ~1 → /, ~0 → ~.
+//
+// Limitation: only object (map) traversal is supported. Array index segments
+// (e.g., "/channels/0/appId") are not implemented because OpenClaw's
+// SecretRef file provider uses object-only paths in practice.
+func ReadJSONPointer(data interface{}, pointer string) (interface{}, error) {
+	if pointer == "" {
+		return data, nil
+	}
+
+	if !strings.HasPrefix(pointer, "/") {
+		return nil, fmt.Errorf("json pointer must start with '/' or be empty, got %q", pointer)
+	}
+
+	// Split after the leading "/" and decode each segment.
+	segments := strings.Split(pointer[1:], "/")
+	current := data
+
+	for i, raw := range segments {
+		// RFC 6901 unescaping: ~1 → /, ~0 → ~ (order matters).
+		key, err := decodeJSONPointerSegment(raw)
+		if err != nil {
+			return nil, fmt.Errorf("json pointer %q: segment %q: %w", pointer, raw, err)
+		}
+
+		m, ok := current.(map[string]interface{})
+		if !ok {
+			traversed := "/" + strings.Join(segments[:i], "/")
+			return nil, fmt.Errorf("json pointer %q: value at %q is %T, not an object",
+				pointer, traversed, current)
+		}
+
+		val, exists := m[key]
+		if !exists {
+			return nil, fmt.Errorf("json pointer %q: key %q not found", pointer, key)
+		}
+
+		current = val
+	}
+
+	return current, nil
+}
+
+func decodeJSONPointerSegment(raw string) (string, error) {
+	var out strings.Builder
+	for i := 0; i < len(raw); i++ {
+		if raw[i] != '~' {
+			out.WriteByte(raw[i])
+			continue
+		}
+		if i+1 >= len(raw) {
+			return "", fmt.Errorf("invalid escape: ~ must be followed by 0 or 1")
+		}
+		switch raw[i+1] {
+		case '0':
+			out.WriteByte('~')
+		case '1':
+			out.WriteByte('/')
+		default:
+			return "", fmt.Errorf("invalid escape: ~%c must be ~0 or ~1", raw[i+1])
+		}
+		i++
+	}
+	return out.String(), nil
+}