如何从HttpResponseMessage反序列化protobuf内容

Question

I'm trying to deserialize the response message from my database in protobuf format. It has this schema:

syntax = "proto3";

message Person {
  uint64 id = 1;
  string name = 2;
  string surname = 3;
  uint32 age = 4;
};

and I created this class to deserialize it:

[ProtoContract]
public class Person
{
    [ProtoMember(1)]
    public long Id { get; set; }
    [ProtoMember(2)]
    public string Name { get; set; }
    [ProtoMember(3)]
    public string Surname { get; set; }
    [ProtoMember(4)]
    public int Age { get; set; }
}

Next, I tried to do this:

var response = await client.PostAsync("", new StringContent(request));
using (var responseStream = await response.Content.ReadAsStreamAsync())
{
    var person = Serializer.Deserialize<Person>(responseStream);
}

But I cathed a ProtoBuf.ProtoException: Invalid wire-type; .

Then I decided to see at byte array:

{25, 8, 1, 18, 6, 82, 111, 98, 101, 114, 116, 26, 11, 79, 112, 112, 101, 110, 104, 101, 105, 109, 101, 114, 32, 38 }

And I created by hand an entry, that must be returned by my database, and serialize it:

{8, 1, 18, 6, 82, 111, 98, 101, 114, 116, 26, 11, 79, 112, 112, 101, 110, 104, 101, 105, 109, 101, 114, 32, 38 }

As you can see, they are almost the same, but my db send 25 at the start.

Could you help me, what could be the error? Thanks!

Answer 1

I realized, that it is due to streaming multiple messages . And in this case, I've rewritten my method to:

List<Person> persons;
using (var responseStream = await response.Content.ReadAsStreamAsync())
{
    persons = Serializer.DeserializeItems<Person>(responseStream, PrefixStyle.Base128, 0).ToList();
}