From 277809ba83e5aac0123da52ba3dda95394bb3c8f Mon Sep 17 00:00:00 2001
From: Renato Westphal <renato@opensourcerouting.org>
Date: Mon, 14 Oct 2024 15:03:25 -0300
Subject: [PATCH] daemon-grpc: update `Capabilities` RPC to return supported
 features per module

It's important to know which features are enabled or disabled, as
this determines which parts of the YANG module are implemented.

gNMI's `Capabilities` RPC doesn't provide this information, since
OpenConfig modules typically don't use "feature" and "if-feature"
statements, unlike IETF models.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>
---
 holo-daemon/src/northbound/client/grpc.rs | 11 ++++++++++-
 proto/holo.proto                          |  3 +++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/holo-daemon/src/northbound/client/grpc.rs b/holo-daemon/src/northbound/client/grpc.rs
index 4a3cec6c..4ecbb8b5 100644
--- a/holo-daemon/src/northbound/client/grpc.rs
+++ b/holo-daemon/src/northbound/client/grpc.rs
@@ -9,7 +9,7 @@ use std::time::SystemTime;
 
 use futures::Stream;
 use holo_utils::Sender;
-use holo_yang::YANG_CTX;
+use holo_yang::{YANG_CTX, YANG_FEATURES};
 use tokio::sync::oneshot;
 use tonic::transport::{Server, ServerTlsConfig};
 use tonic::{Request, Response, Status};
@@ -63,6 +63,15 @@ impl proto::Northbound for NorthboundService {
                     .unwrap_or_default()
                     .to_owned(),
                 revision: module.revision().unwrap_or_default().to_owned(),
+                supported_features: YANG_FEATURES
+                    .get(&module.name())
+                    .map(|features| {
+                        features
+                            .iter()
+                            .map(|feature| (*feature).to_owned())
+                            .collect()
+                    })
+                    .unwrap_or_default(),
             })
             .collect();
 
diff --git a/proto/holo.proto b/proto/holo.proto
index 985c0f7d..1fb4af72 100644
--- a/proto/holo.proto
+++ b/proto/holo.proto
@@ -231,6 +231,9 @@ message ModuleData {
 
   // Latest revision of the module;
   string revision = 3;
+
+  // Supported features.
+  repeated string supported_features = 4;
 }
 
 // Supported encodings for YANG instance data.