HttpClient metrics report server.port unconditionally
When HttpClient metrics were added in .NET 8, server.port was introduced as a Conditionally Required attribute in accordance with the state of the standard at that time. Being conditionally required meant that the port was only reported if it did not match the default port of the corresponding protocol (80 for HTTP, 443 for HTTPS). However, the standard requirement level of the attribute has since been changed to Required.
To maintain compliance with the Open Telemetry standard while keeping the instrument's behaviors consistent with each other, the instruments http.client.request.duration, http.client.connection.duration, and http.client.open_connections have been changed to unconditionally report the server.port attribute.
This change can break existing queries in monitoring software like Prometheus.
Version introduced
.NET 9 Preview 7
Previous behavior
http.client.request.duration, http.client.connection.duration, and http.client.open_connections reported the server.port attribute only if it did not match the corresponding protocol's default port (80 for HTTP, 443 for HTTPS).
New behavior
The server.port attribute is now unconditionally reported by the instruments http.client.request.duration, http.client.connection.duration, and http.client.open_connections.
Type of breaking change
This change is a behavioral change.
Reason for change
The change maintains compliance with the Open Telemetry specification while keeping HttpClient instruments consistent with each other.
Recommended action
No action is needed if you don't rely on HttpClient metrics. If you use the http.client.request.duration, http.client.connection.duration, or http.client.open_connections instruments, this change might break existing queries in monitoring software like Prometheus.
Affected APIs
System.Net.Http.SocketsHttpHandler.Send(System.Net.Http.HttpRequestMessage,System.Threading.CancellationToken)System.Net.Http.SocketsHttpHandler.SendAsync(System.Net.Http.HttpRequestMessage,System.Threading.CancellationToken)- System.Net.Http.HttpClientHandler.Send(HttpRequestMessage, CancellationToken)
- System.Net.Http.HttpClientHandler.SendAsync(HttpRequestMessage, CancellationToken)
