protobuf-net throws exception about invalid wire-type, when passing single enum values to WCF service

Question

Calling the following method on my wcf service….

ObservableCollection<PatientViewModel> Search(List<string> searchTerms, SearchNature nature, SearchMode mode, List<SearchField> fields)

Result in the following exception…

ProtoBuf.ProtoException, protobuf-net, Version=2.0.0.627, Culture=neutral, PublicKeyToken=75e2634e27c46854

Invalid wire-type; this usually means you have over-written a file without truncating or setting the length; see http://stackoverflow.com/q/2152978/23354

ProtoBuf.ProtoReader.ReadInt32()
proto_4(Object , ProtoReader )
ProtoBuf.ServiceModel.XmlProtoSerializer.ReadObject(XmlDictionaryReader reader, Boolean verifyObjectName)
System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.PartInfo.ReadObject(XmlDictionaryReader reader, XmlObjectSerializer serializer)
System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.DeserializeParameterPart(XmlDictionaryReader reader, PartInfo part, Boolean isRequest)
System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.DeserializeParameters(XmlDictionaryReader reader, PartInfo[] parts, Object[] parameters, Boolean isRequest)
System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.DeserializeBody(XmlDictionaryReader reader, MessageVersion version, String action, MessageDescription messageDescription, Object[] parameters, Boolean isRequest)
System.ServiceModel.Dispatcher.OperationFormatter.DeserializeBodyContents(Message message, Object[] parameters, Boolean isRequest)
System.ServiceModel.Dispatcher.OperationFormatter.DeserializeRequest(Message message, Object[] parameters)
System.ServiceModel.Dispatcher.DispatchOperationRuntime.DeserializeInputs(MessageRpc&amp; rpc)
System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc&amp; rpc)
System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc&amp; rpc)
System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage31(MessageRpc&amp; rpc)
System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)

NOTE: If I remove the 2nd and 3rd parameters. So the method is…

ObservableCollection<PatientViewModel> Search(List<string> searchTerms, List<SearchField> fields)

This works fine.

The parameter fields is an enum list and that deserializes with no issue.

Why would a single enum value cause the above exception?

Thanks in advance.

For your reference...

[DataContract]
public enum SearchNature
{
    [EnumMember] None,
    [EnumMember] Letters,
    [EnumMember] Numbers
}

[DataContract]
public enum SearchMode
{
    [EnumMember] None,
    [EnumMember] BeginsWith,
    [EnumMember] Contains
}

[DataContract]
public enum SearchField
{
    [EnumMember] None,
    [EnumMember] FirstName,
    [EnumMember] LastName,
    [EnumMember] PatientId,
    [EnumMember] PriorId,
    [EnumMember] PhoneNumber,
    [EnumMember] DateOfBirth
}

Edit:

Additionally, if I change ProtoOperationBehavior to use the default serializer when the type is an enum instead of XmlProtoSerializer, the service calls work fine.

public override XmlObjectSerializer CreateSerializer(Type type, System.Xml.XmlDictionaryString name, System.Xml.XmlDictionaryString ns, IList<Type> knownTypes)
{
    if (type.IsEnum) return base.CreateSerializer(type, name, ns, knownTypes);
    if (model == null) throw new InvalidOperationException("No Model instance has been assigned to the ProtoOperationBehavior");
    return XmlProtoSerializer.TryCreate(model, type) ?? base.CreateSerializer(type, name, ns, knownTypes);
}

Furthermore if I convert the 2nd and 3rd parameters to integers...it works fine. I just cast to int when I call the method and once inside the method at the wcf service, I cast to enum respectively. — Brian Singh, Feb 28 '13 at 23:13
try making your Enums inherit from Int public enum SearchField : int — Paul Farry, Feb 28 '13 at 23:49
@paul, Specifying the enumeration type to be int is redundant because, by default, int is the default governing type for enumeration members. I can obviously get this working with the cast to int and cast back to enum. I am ultimately trying to understand why the enums are not deserializing. — Brian Singh, Mar 01 '13 at 15:03

score 1 · Answer 1 · answered Feb 28 '13 at 22:14

1

Enums, int, double, string, etc are not valid protocol buffer messages by themselves. You have to make them fields or properties of an object and then serialize that object.

answered Feb 28 '13 at 22:14

Timothy Shields

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score 0 · Answer 2 · answered Feb 28 '13 at 23:06

If you make a class and pass that into your search instead you should get what you need. Hopefully this will help.

If you then have the serializer in place it will give you back an operational class object.

[ProtoContract()]
public class PatientSearch
{
    public PatientSearch()
    {
        searchTerms = new List<string>();
        fields = new List<SearchField>();
    }
    [ProtoMember(1)]
    public List<string>searchTerms {get;private set;}

    [ProtoMember(2)]
    public SearchNature Nature {get; set;}
    [ProtoMember(3)]
    public SearchMode Nature {get; set;}
    [ProtoMember(4)]
    public  List<SearchField> fields {get; private set;}

}

protobuf-net throws exception about invalid wire-type, when passing single enum values to WCF service

2 Answers2