Real-time and RPC: SignalR, gRPC, webhooks — ASP.NET Core Web API & REST

14. Real-time and RPC: SignalR, gRPC, webhooks

AdvancedMediumLesson 14 of 15

SignalR — server push to clients over WebSockets (fallback: Server-Sent Events, long polling). Hubs, groups, Azure SignalR Service for scale-out. Use for chat, dashboards, notifications.
gRPC — contract-first (.proto), HTTP/2, binary Protobuf, streaming (server, client, bidirectional), generated clients. Great for internal service-to-service calls; browsers need gRPC-Web.
Webhooks — your API calls the client's URL when events happen; sign payloads (HMAC), retry with backoff, idempotency.
Server-Sent Events — one-way server → browser streaming over HTTP (.NET 10 adds TypedResults.ServerSentEvents).