1. Reference
  2. Server Methods

NewServer

The NewServer(... Services, *tls.Config, *zerolog.Logger) (*Server, error) method is used to create a new fRPC Server. It takes a list of structs that implement the RPC methods corresponding to the services defined in the .proto file.

For example, if the .proto file contains the following service definition:

service MyService {
  rpc MyMethod(MyRequest) returns (MyResponse) {}
}

service OtherService {
  rpc OtherMethod(MyRequest) returns (MyResponse) {}
}

Then the generated service implementation interfaces are expected:

type MyService interface {
	MyMethod(context.Context, *MyRequest) (*MyResponse, error)
}

type OtherService interface {
    OtherMethod(context.Context, *MyRequest) (*MyResponse, error)
}

And the corresponding generated NewServer method would be:

func NewServer(myService MyService, otherService OtherService, tlsConfig *tls.Config, logger *zerolog.Logger) (*Server, error) {
    ...
}

The generated NewServer method also takes the additional two arguments:

  • tlsConfig: a *tls.Config that will be used to configure TLS for fRPC server. This can be left as nil if no TLS is required.
  • logger: a *zerolog.Logger that will be used to log all events. This can be left as nil if no logging is required.

It returns an fRPC *Server on success and an error otherwise.

For long-running RPC handlers it’s important to pay attention to the passed on context.Context - it will be cancelled when the server is shutdown and handlers are expected to return as soon as that happens.

SetBaseContext

The SetBaseContext(f func() context.Context) error method is used to set the base context for all incoming RPCs. This is useful if you want to set a common context for all incoming RPCs.

SetOnClosed

The SetOnClosed(f func(*frisbee.Async, error)) error method is used to set the callback function that will be called when a connection to an fRPC client is closed. This is useful if you want to do any cleanup when a connection to a client is closed.

SetHandlerTable

The SetHandlerTable(handlerTable frisbee.HandlerTable) error method is used to set the handler table for the fRPC server. This is useful if you want to set a custom handler table for the fRPC server, and is commonly used to extend the fRPC server with custom handlers for alternative messaging patterns. In order to avoid breaking the fRPC functionality, it’s recommended to first use the GetHandlerTable method to retrieve the base handler table, modify it, and then use the SetHandlerTable method to set the modified handler table.

GetHandlerTable

The GetHandlerTable() frisbee.HandlerTable method is used to retrieve the handler table for the fRPC server. This is useful if you want to retrieve and extend handler table for the fRPC server, and is commonly used with the SetHandlerTable method.

SetPreWrite

The SetPreWrite(f func()) error method is used to set the pre-write callback function for the fRPC server. This is useful if you want to handle metrics or do some logging before a request is written to the client.

SetConcurrency

The SetConcurrency(concurrency uint64) method is used to set the concurrency for the fRPC server. This is useful if you want to set a maximum number of concurrent goroutines that can be spawned by the fRPC server (across all clients).

Setting this value to 0 will result in the fRPC server spawning an unlimited number of goroutines to handle incoming RPCs, and setting the value to 1 will result in the fRPC server spawning a single goroutine (per fRPC Client) to handle incoming RPCs.

All other values will result in the fRPC server spawning (at maximum) the specified number of goroutines to handle incoming RPCs.

Start

The Start(addr string) error method is used to start the fRPC server. It takes the address to listen on as an argument and will return an error if the server fails to start.

ServeConn

The ServeConn(conn net.Conn) method is used to serve a given net.Conn. It takes the connection to serve as an argument and is a non-blocking method - it will return immediately after starting to serve the connection in a separate goroutine, and if it encounters an error, the OnClosed callback function will be called with the error.

Logger

The Logger() *zerolog.Logger method is used to retrieve the logger for the fRPC server. This is useful if you want to retrieve and extend the fRPC server.

Shutdown

The Shutdown() error method is used to shutdown the fRPC server. It will return an error if the server fails to shutdown, and it will clean up all goroutines spawned by the server before returning. Any active connections will be closed before the server is shutdown, and any active RPCs will be cancelled. The contexts given to the RPCs will be cancelled as well.

Generated Interfaces

When generating the fRPC Server, each service in the .proto file requires a service implementation that fulfills the RPC methods defined for the service.

For example, if the .proto file contains the following service definition:

service MyService {
  rpc MyMethod(MyRequest) returns (MyResponse) {}
}

then the generated service implementation interface looks like this:

type MyService interface {
	MyMethod(context.Context, *MyRequest) (*MyResponse, error)
}

This is a similar function signature to the one gRPC would generate, making it easy to reuse the service implementation from gRPC.