From 8861fc493bda14f3fd15cb6517be8317d4b3e9ac Mon Sep 17 00:00:00 2001
From: Mathieu Duponchelle <mathieu@centricular.com>
Date: Mon, 6 May 2024 13:36:47 +0200
Subject: [PATCH] webrtcsink: improve error when no discovery pipeline runs

If for instance no encoder was found or the RTP plugin was missing,
it is possible that no discovery pipeline will run for a given stream.

Provide a more helpful error message for that case.

Fixes: https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/issues/534
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1560>
---
 net/webrtc/src/webrtcsink/imp.rs | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/net/webrtc/src/webrtcsink/imp.rs b/net/webrtc/src/webrtcsink/imp.rs
index 3d8ec849..86e7ae38 100644
--- a/net/webrtc/src/webrtcsink/imp.rs
+++ b/net/webrtc/src/webrtcsink/imp.rs
@@ -3527,6 +3527,15 @@ impl BaseWebRTCSink {
         } else {
             let sink_caps = discovery_info.caps.clone();
 
+            if codecs.is_empty() {
+                return Err(anyhow!(
+                    "No codec available for encoding stream {}, \
+                                   check the webrtcsink logs and verify that \
+                                   the rtp plugin is available",
+                    name
+                ));
+            }
+
             let is_video = match sink_caps.structure(0).unwrap().name().as_str() {
                 "video/x-raw" => true,
                 "audio/x-raw" => false,