Creating Relationships Between Entities in gRPC Using Proto Files

Hi Kamyab Faghih,

You could use repeated to define one-to-many field in proto files. Such as following:

Protos/Service1.proto

syntax = "proto3";
option csharp_namespace = "WebApplication310.Protos";
service Service1 {
  rpc GetOrder(OrderRequest) returns (Order);
}
message OrderRequest{
    int32 orderId =1;
}
message Order {
  int32 orderId = 1;
  repeated Item items=2;
}
message Item {
    int32 id = 1;
    string name = 2;
}

Then you could make use the Order entity like following:

MyService.cs

    public class MyService : WebApplication310.Protos.Service1.Service1Base
    {
        public override Task<Order> GetOrder(OrderRequest request, ServerCallContext context)
        {
            var items = new List<Item>
            {
                new Item { Id = 1, Name = "Apple" },
                new Item { Id = 2, Name = "Orange" }
            };

            return Task.FromResult(new Order
            {
                OrderId = request.OrderId,
                Items = { items }
            });
        }
    }

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