使用golang gRPC客户端拨打多个IP地址

Question

I have grpc server 192.168.1.12:8800 and 192.168.1.13:8800, I want to connect them use grpc.Dial with ip list, not server discover, How can I do?

conn, err = grpc.Dial("192.168.1.12:8800,192.168.1.13:8800", grpc.WithInsecure())

with error

rpc error: code = Unavailable desc = all SubConns are in TransientFailure, latest connection error: connection error: desc = \"transport: Error while dialing dial tcp: too many colons in address 192.168.1.12:8800,192.168.1.13:8800

Answer 1

Unfortunately, you aren't able to pass multiple IP addresses using grpc.Dial(...), it only takes a single argument.

gRPC in Go does have an "experimental" load balancer api that you should be able to take advantage of.

An example of the resolver you would need to write can be found here. It creates a fake resolver that will load balance across the multiple IP addresses.

So once you have a resolver such as that, the code you would want would look something like this:

conn, err := grpc.Dial(
    "",
    grpc.WithInsecure(),
    grpc.WithBalancer(grpc.RoundRobin(resolver.NewPseudoResolver([]string{
        "10.0.0.1:10000",
        "10.0.0.2:10000",
    }))),
)