golang GRPC 携带上下文信息

使用context.Context

上下文去全局数据 metadata

type MD map[string][]string

//第一种方式
md := metadata.New(map[string]string{"key1": "val1", "key2": "val2"})
 
//第二种方式 key不区分大小写，会被统一转成小写
md := metadata.Pairs(
    "key1", "val1",
    "key1", "val1-2", // "key1" will have map value []string{"val1", "val1-2"}
    "key2", "val2",
)

客户端传值

func (s *server) SomeRPC(ctx context.Context, in *pb.SomeRequest) (*pb.SomeResponse, err) {
    md, ok := metadata.FromIncomingContext(ctx)
    // do something with metadata
}

服务端获取参数

func (s *server) SomeRPC(ctx context.Context, in *pb.SomeRequest) (*pb.SomeResponse, err) {
    md, ok := metadata.FromIncomingContext(ctx)
    // do something with metadata
}