Surface L7 traffic details in the traffic graph (HTTP method, path, status codes)

[nadaverell]

Idea

When Hubble is the active traffic source, it provides rich L7 data per flow: HTTP method, path, status code, gRPC protocol, and per-service request/error rates. Currently this data is collected in the backend Flow struct but never surfaced in the traffic graph UI — edges only show connection counts and bytes.

What this could look like

Clicking an edge in the traffic graph when Hubble is active could show:

• Top endpoints: GET /api/health → 200 (1.2k req/s), POST /checkout → 500 (3 req/s)
• HTTP status breakdown (2xx / 4xx / 5xx)
• Error rate highlighted in red when above a threshold
• gRPC status codes when applicable

This would make the Hubble experience meaningfully richer than what you get from Grafana dashboards, and is the clearest differentiator between Radar and a generic metrics tool.

Scope

Frontend-only change — the data already flows from Hubble through to the API response. The work is in the edge detail panel in TrafficGraph.tsx.

Related

• Only meaningful when Hubble is the active source; Caretta and Istio provide aggregate rates but not per-endpoint breakdown