From 776c4db845ed9c37a8f0aa9aa186e34e29fa1e5c Mon Sep 17 00:00:00 2001
From: Kuat <kyessenov@users.noreply.github.com>
Date: Wed, 11 Oct 2023 12:04:38 -0700
Subject: [PATCH] cel: add a description to the AST (#61)

Signed-off-by: Kuat Yessenov <kuat@google.com>
---
 go/xds/type/matcher/v3/cel.pb.go          | 30 +++++++++++++++--------
 go/xds/type/matcher/v3/cel.pb.validate.go |  2 ++
 xds/type/matcher/v3/cel.proto             |  4 +++
 3 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/go/xds/type/matcher/v3/cel.pb.go b/go/xds/type/matcher/v3/cel.pb.go
index 24b19ac0..ef8b175f 100644
--- a/go/xds/type/matcher/v3/cel.pb.go
+++ b/go/xds/type/matcher/v3/cel.pb.go
@@ -33,7 +33,8 @@ type CelMatcher struct {
 	sizeCache     protoimpl.SizeCache
 	unknownFields protoimpl.UnknownFields
 
-	ExprMatch *v3.CelExpression `protobuf:"bytes,1,opt,name=expr_match,json=exprMatch,proto3" json:"expr_match,omitempty"`
+	ExprMatch   *v3.CelExpression `protobuf:"bytes,1,opt,name=expr_match,json=exprMatch,proto3" json:"expr_match,omitempty"`
+	Description string            `protobuf:"bytes,2,opt,name=description,proto3" json:"description,omitempty"`
 }
 
 func (x *CelMatcher) Reset() {
@@ -75,6 +76,13 @@ func (x *CelMatcher) GetExprMatch() *v3.CelExpression {
 	return nil
 }
 
+func (x *CelMatcher) GetDescription() string {
+	if x != nil {
+		return x.Description
+	}
+	return ""
+}
+
 var File_xds_type_matcher_v3_cel_proto protoreflect.FileDescriptor
 
 var file_xds_type_matcher_v3_cel_proto_rawDesc = []byte{
@@ -86,19 +94,21 @@ var file_xds_type_matcher_v3_cel_proto_rawDesc = []byte{
 	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x1a, 0x15, 0x78, 0x64, 0x73, 0x2f, 0x74, 0x79, 0x70, 0x65, 0x2f,
 	0x76, 0x33, 0x2f, 0x63, 0x65, 0x6c, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x1a, 0x17, 0x76, 0x61,
 	0x6c, 0x69, 0x64, 0x61, 0x74, 0x65, 0x2f, 0x76, 0x61, 0x6c, 0x69, 0x64, 0x61, 0x74, 0x65, 0x2e,
-	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x22, 0x51, 0x0a, 0x0a, 0x43, 0x65, 0x6c, 0x4d, 0x61, 0x74, 0x63,
+	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x22, 0x73, 0x0a, 0x0a, 0x43, 0x65, 0x6c, 0x4d, 0x61, 0x74, 0x63,
 	0x68, 0x65, 0x72, 0x12, 0x43, 0x0a, 0x0a, 0x65, 0x78, 0x70, 0x72, 0x5f, 0x6d, 0x61, 0x74, 0x63,
 	0x68, 0x18, 0x01, 0x20, 0x01, 0x28, 0x0b, 0x32, 0x1a, 0x2e, 0x78, 0x64, 0x73, 0x2e, 0x74, 0x79,
 	0x70, 0x65, 0x2e, 0x76, 0x33, 0x2e, 0x43, 0x65, 0x6c, 0x45, 0x78, 0x70, 0x72, 0x65, 0x73, 0x73,
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-	0x76, 0x33, 0xd2, 0xc6, 0xa4, 0xe1, 0x06, 0x02, 0x08, 0x01, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74,
-	0x6f, 0x33,
+	0x78, 0x70, 0x72, 0x4d, 0x61, 0x74, 0x63, 0x68, 0x12, 0x20, 0x0a, 0x0b, 0x64, 0x65, 0x73, 0x63,
+	0x72, 0x69, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x18, 0x02, 0x20, 0x01, 0x28, 0x09, 0x52, 0x0b, 0x64,
+	0x65, 0x73, 0x63, 0x72, 0x69, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x42, 0x60, 0x0a, 0x1e, 0x63, 0x6f,
+	0x6d, 0x2e, 0x67, 0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x78, 0x64, 0x73, 0x2e, 0x74, 0x79, 0x70,
+	0x65, 0x2e, 0x6d, 0x61, 0x74, 0x63, 0x68, 0x65, 0x72, 0x2e, 0x76, 0x33, 0x42, 0x08, 0x43, 0x65,
+	0x6c, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x50, 0x01, 0x5a, 0x2a, 0x67, 0x69, 0x74, 0x68, 0x75, 0x62,
+	0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x63, 0x6e, 0x63, 0x66, 0x2f, 0x78, 0x64, 0x73, 0x2f, 0x67, 0x6f,
+	0x2f, 0x78, 0x64, 0x73, 0x2f, 0x74, 0x79, 0x70, 0x65, 0x2f, 0x6d, 0x61, 0x74, 0x63, 0x68, 0x65,
+	0x72, 0x2f, 0x76, 0x33, 0xd2, 0xc6, 0xa4, 0xe1, 0x06, 0x02, 0x08, 0x01, 0x62, 0x06, 0x70, 0x72,
+	0x6f, 0x74, 0x6f, 0x33,
 }
 
 var (
diff --git a/go/xds/type/matcher/v3/cel.pb.validate.go b/go/xds/type/matcher/v3/cel.pb.validate.go
index c079a2a9..6f165a12 100644
--- a/go/xds/type/matcher/v3/cel.pb.validate.go
+++ b/go/xds/type/matcher/v3/cel.pb.validate.go
@@ -57,6 +57,8 @@ func (m *CelMatcher) Validate() error {
 		}
 	}
 
+	// no validation rules for Description
+
 	return nil
 }
 
diff --git a/xds/type/matcher/v3/cel.proto b/xds/type/matcher/v3/cel.proto
index d9ed065b..b1ad1faa 100644
--- a/xds/type/matcher/v3/cel.proto
+++ b/xds/type/matcher/v3/cel.proto
@@ -35,4 +35,8 @@ option (xds.annotations.v3.file_status).work_in_progress = true;
 message CelMatcher {
   // Either parsed or checked representation of the CEL program.
   type.v3.CelExpression expr_match = 1 [(validate.rules).message = {required: true}];
+
+  // Free-form description of the CEL AST, e.g. the original expression text, to be
+  // used for debugging assistance.
+  string description = 2;
 }