예제 #1
0
        private void MergeAny(IMessage message, JsonTokenizer tokenizer)
        {
            // Record the token stream until we see the @type property. At that point, we can take the value, consult
            // the type registry for the relevant message, and replay the stream, omitting the @type property.
            var tokens = new List <JsonToken>();

            var token = tokenizer.Next();

            if (token.Type != JsonToken.TokenType.StartObject)
            {
                throw new InvalidProtocolBufferException("Expected object value for Any");
            }
            int typeUrlObjectDepth = tokenizer.ObjectDepth;

            // The check for the property depth protects us from nested Any values which occur before the type URL
            // for *this* Any.
            while (token.Type != JsonToken.TokenType.Name ||
                   token.StringValue != JsonFormatter.AnyTypeUrlField ||
                   tokenizer.ObjectDepth != typeUrlObjectDepth)
            {
                tokens.Add(token);
                token = tokenizer.Next();

                if (tokenizer.ObjectDepth < typeUrlObjectDepth)
                {
                    throw new InvalidProtocolBufferException("Any message with no @type");
                }
            }

            // Don't add the @type property or its value to the recorded token list
            token = tokenizer.Next();
            if (token.Type != JsonToken.TokenType.StringValue)
            {
                throw new InvalidProtocolBufferException("Expected string value for Any.@type");
            }
            string typeUrl  = token.StringValue;
            string typeName = Any.GetTypeName(typeUrl);

            MessageDescriptor descriptor = settings.TypeRegistry.Find(typeName);

            if (descriptor == null)
            {
                throw new InvalidOperationException($"Type registry has no descriptor for type name '{typeName}'");
            }

            // Now replay the token stream we've already read and anything that remains of the object, just parsing it
            // as normal. Our original tokenizer should end up at the end of the object.
            var replay = JsonTokenizer.FromReplayedTokens(tokens, tokenizer);
            var body   = descriptor.Parser.CreateTemplate();

            if (descriptor.IsWellKnownType)
            {
                MergeWellKnownTypeAnyBody(body, replay);
            }
            else
            {
                Merge(body, replay);
            }
            var data = body.ToByteString();

            // Now that we have the message data, we can pack it into an Any (the message received as a parameter).
            message.Descriptor.Fields[Any.TypeUrlFieldNumber].Accessor.SetValue(message, typeUrl);
            message.Descriptor.Fields[Any.ValueFieldNumber].Accessor.SetValue(message, data);
        }