Unary or StreamingHub
MagicOnion provides two types of API implementation methods: Unary services and StreamingHub services. You can define RPC-style APIs using either of these methods.
The differences between Unary and StreamingHub are as follows:
- Unary is a simple HTTP POST request that processes one request and one response at a time
- StreamingHub is bidirectional communication that sends messages between the client and server using a continuous connection
You can implement everything with StreamingHub, but for general APIs that do not require notifications from the server (e.g., REST or Web APIs), it is recommended to use Unary.
Benefits of Unary
- Load Balancing and Observability
- Unary is essentially an HTTP POST call, so it is compatible with existing eco systems such as ASP.NET Core, load balancers, CDNs, and WAFs
- StreamingHub is a single long request, and it is difficult to log internal Hub method calls at the infrastructure level
- This means that Hub method calls cannot be load balanced
- Overhead of StreamingHub
- Unary is essentially a simple HTTP POST, and does not require the establishment of a connection like StreamingHub
- StreamingHub has additional overhead such as starting a message loop and setting up a heartbeat during connection
Benefits of StreamingHub
- Real-time message sending from the server to the client (including multiple clients)
- If notifications from the server to the client are required, consider using StreamingHub
- This is recommended for chat message notifications, game position synchronization, etc.
- It replaces the need for polling/long polling with Unary or regular HTTP requests