How do you implement gRPC streaming including server-side, client-side, and bidirectional streaming in NestJS?

Q: How do you implement gRPC streaming including server-side, client-side, and bidirectional streaming in NestJS?

// Proto: // rpc ListUsers (ListUsersRequest) returns (stream User); // rpc CreateUsers (stream CreateUserRequest) returns (Summary); // Server-side streaming — returns Observable @GrpcStreamMethod('UsersService', 'ListUsers') listUsers(data: ListUsersRequest): Observable { return new Observable(observer => { this.usersService.findAll(data).then(users => { for (const user of users) observer.next(user); observer.complete(); }); }); } // Client-side streaming — receives Observable of incoming messages @GrpcStreamMethod('UsersService', 'CreateUsers') createUsers(messages$: Observable ): Observable { return new Observable(observer => { let count = 0; messages$.subscribe({ next: async msg => { await this.usersService.create(msg); count++; }, complete: () => { observer.next({ created: count }); observer.complete(); }, }); }); } // Call from gRPC client const usersService = this.grpcClient.getService ('UsersService'); const stream$ = usersService.listUsers({ page: 1, limit: 50 }); stream$.subscribe(user => console.log(user)); Server streaming — use for large dataset exports; client receives items as they become available. Client streaming — use for bulk ingestion; server processes a stream of items and returns a summary. Bidirectional streaming — use for real-time chat or live feeds; both sides send and receive concurrently. @GrpcStreamMethod() handles all streaming types — NestJS infers direction from the Observable positions. HTTP/2 multiplexing enables many concurrent streams over a single connection — very efficient for bulk transfers.

Difficulty: 7/10

server-side streaming, client-side streaming, bidirectional streaming

Server-side streaming returns an Observable<T> from the handler. Client-side streaming receives an Observable<T> as the first argument. Bidirectional streaming both receives and returns an Observable. NestJS maps these to the gRPC streaming types via @GrpcStreamMethod() and @GrpcStreamCall() decorators.

Server-side and client-side streaming handlers

gRPC streaming patterns:

1
Server streaming — use for large dataset exports; client receives items as they become available.
2

How do you implement gRPC streaming including server-side, client-side, and bidirectional streaming in NestJS?

Difficulty: 7/10

server-side streaming, client-side streaming, bidirectional streaming

Server-side streaming returns an Observable<T> from the handler. Client-side streaming receives an Observable<T> as the first argument. Bidirectional streaming both receives and returns an Observable. NestJS maps these to the gRPC streaming types via @GrpcStreamMethod() and @GrpcStreamCall() decorators.

Server-side and client-side streaming handlers

gRPC streaming patterns:

1
Server streaming — use for large dataset exports; client receives items as they become available.
2

How do you implement gRPC streaming including server-side, client-side, and bidirectional streaming in NestJS?

How do you implement gRPC streaming including server-side, client-side, and bidirectional streaming in NestJS?

Scenario Questions

Follow-up Questions