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[英]Sending protobuf serialized object from c# to java server not working?
[英]Protobuf serialized object to json
我有一些使用 protobuf 序列化並存儲在數據庫中的標准對象。 是否可以將對象反序列化為通用標記(例如 json 或 xml)並返回到序列化的對象類型 protobuf 而不具有該類的具體實現?
[ProtoContract]
[Serializable]
internal class SomeDTO
{
/// <summary>
/// Gets or sets the Id.
/// </summary>
[ProtoMember(1)]
public string MyKey { get; set; }
[ProtoMember(2)]
public string Name { get; set; }
[ProtoMember(3)]
public int SomeId { get; set; }
[ProtoMember(4)]
public DateTime LastModifiedDate { get; set; }
}
該對象將序列化為:
{
"1": "asdklfhkajd",
"2": "Tim",
"3": 12345,
"4": "05/29/2015 5:50"
}
或者如果我描述符過來但不是必需的:
{
"MyKey": "asdklfhkajd",
"Name": "Tim",
"SomeId": 12345,
"LastModifiedDate": "05/29/2015 5:50"
}
我正在考慮可能用 ProtoReader 寫一些東西嗎?
元數據對象:
public class collectionMetadata
{
public string Field { get; set; }
public string FieldType { get; set; }
}
解串器:
public static JObject ProtoReaderDeserilizer(List<CollectionFieldType> collectionMetadata, ProtoReader reader)
{
JObject obj = new JObject();
while (reader.ReadFieldHeader() > 0)
{
var field = collectionMetadata[reader.FieldNumber - 1].Field;
switch (reader.WireType)
{
case WireType.Variant:
obj[field] = reader.ReadInt64();
break;
case WireType.String:
var fieldType = collectionMetadata[reader.FieldNumber - 1].FieldType;
switch (fieldType.ToLowerInvariant())
{
case "date":
var tok1 = ProtoReader.StartSubItem(reader);
reader.ReadFieldHeader();
switch (reader.WireType)
{
case WireType.Variant:
obj[field] = reader.ReadInt64();
break;
default:
reader.ReadFieldHeader();
break;
}
ProtoReader.EndSubItem(tok1, reader);
break;
case "datetime":
obj[field] = BclHelpers.ReadDateTime(reader);
break;
case "decimal":
obj[field] = BclHelpers.ReadDecimal(reader);
break;
case "guid":
obj[field] = BclHelpers.ReadGuid(reader);
break;
case "string":
default:
if (!fieldType.StartsWith("["))
obj[field] = reader.ReadString();
else
{
var tok2 = ProtoReader.StartSubItem(reader);
obj[field] = ProtoReaderDeserilizer(JsonConvert.DeserializeObject<List<CollectionFieldType>>(fieldType), reader);
ProtoReader.EndSubItem(tok2, reader);
}
break;
}
break;
case WireType.Fixed32:
obj[field] = reader.ReadSingle();
break;
case WireType.Fixed64:
obj[field] = reader.ReadDouble();
break;
case WireType.StartGroup:
// one of 2 sub-object formats
var tok = ProtoReader.StartSubItem(reader);
obj[field] = ProtoReaderDeserilizer(JsonConvert.DeserializeObject<List<CollectionFieldType>>(collectionMetadata[reader.FieldNumber - 1].FieldType), reader);
ProtoReader.EndSubItem(tok, reader);
break;
default:
reader.SkipField();
break;
}
}
return obj;
}
序列化器:
public static void ProtoSerializer(ProtoWriter writer, JObject obj, List<CollectionFieldType> collectionMetadata, string name)
{
int i = 1;
if (obj == null)
{
throw new FormatException($"Collection {name} has invalid object defined in its field types. Ensure your collection schema and field times schema match.");
}
foreach (var field in collectionMetadata)
{
string exType = string.Empty;
if (obj.TryGetValue(field.Field, out var fieldToken))
exType = SerializeField(writer, name, i, field, exType, fieldToken);
if (!string.IsNullOrEmpty(exType))
throw new FormatException($"Collection: {name}, Field: {field.Field} invalid {exType} value: {fieldToken.ToString()}");
i++;
}
}
private static void SerializeDefaultValue(ProtoWriter writer, int i, CollectionFieldType field)
{
switch (field.FieldType.ToLowerInvariant())
{
case "bool":
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteBoolean(default, writer);
break;
case "byte":
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteByte(default, writer);
break;
case "sbyte":
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteSByte(default, writer);
break;
case "decimal":
ProtoWriter.WriteFieldHeader(i, WireType.Fixed64, writer);
BclHelpers.WriteDecimal(default, writer);
break;
case "double":
ProtoWriter.WriteFieldHeader(i, WireType.Fixed64, writer);
ProtoWriter.WriteDouble(default, writer);
break;
case "float":
ProtoWriter.WriteFieldHeader(i, WireType.Fixed64, writer);
ProtoWriter.WriteDouble(default, writer);
break;
case "int":
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteInt32(default, writer);
break;
case "enum":
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteInt32(default, writer);
break;
case "long":
ProtoWriter.WriteFieldHeader(i, WireType.Fixed64, writer);
ProtoWriter.WriteInt64(default, writer);
break;
case "short":
ProtoWriter.WriteFieldHeader(i, WireType.Fixed32, writer);
ProtoWriter.WriteInt16(default, writer);
break;
case "date":
ProtoWriter.WriteFieldHeader(i, WireType.String, writer);
var dateToken = ProtoWriter.StartSubItem(field, writer);
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteInt32(default, writer);
ProtoWriter.EndSubItem(dateToken, writer);
break;
case "datetime":
ProtoWriter.WriteFieldHeader(i, WireType.String, writer);
BclHelpers.WriteDateTime(default, writer);
break;
case "guid":
ProtoWriter.WriteFieldHeader(i, WireType.String, writer);
BclHelpers.WriteGuid(default, writer);
break;
case "char":
case "string":
default:
ProtoWriter.WriteFieldHeader(i, WireType.String, writer);
ProtoWriter.WriteString(string.Empty, writer);
break;
}
}
private static string SerializeField(ProtoWriter writer, string name, int i, CollectionFieldType field, string exType, JToken fieldToken)
{
switch (field.FieldType.ToLowerInvariant())
{
case "bool":
if (bool.TryParse(fieldToken.ToString(), out bool boolVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteBoolean(boolVal, writer);
}
else
{
exType = "bool";
}
break;
case "byte":
if (byte.TryParse(fieldToken.ToString(), out byte byteVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteByte(byteVal, writer);
}
else
{
exType = "byte";
}
break;
case "sbyte":
if (sbyte.TryParse(fieldToken.ToString(), out sbyte sbyteVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteSByte(sbyteVal, writer);
}
else
{
exType = "sbyte";
}
break;
case "decimal":
if (decimal.TryParse(fieldToken.ToString(), out decimal decimalVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.Fixed64, writer);
BclHelpers.WriteDecimal(decimalVal, writer);
}
else
{
exType = "decimal";
}
break;
case "double":
if (double.TryParse(fieldToken.ToString(), out double doubleVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.Fixed64, writer);
ProtoWriter.WriteDouble(doubleVal, writer);
}
else
{
exType = "double";
}
break;
case "float":
if (float.TryParse(fieldToken.ToString(), out float floatVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.Fixed64, writer);
ProtoWriter.WriteDouble(floatVal, writer);
}
else
{
exType = "float";
}
break;
case "enum":
case "int":
if (int.TryParse(fieldToken.ToString(), out int intVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteInt32(intVal, writer);
}
else
{
exType = "int";
}
break;
case "long":
if (long.TryParse(fieldToken.ToString(), out long longVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.Fixed64, writer);
ProtoWriter.WriteInt64(longVal, writer);
}
else
{
exType = "long";
}
break;
case "short":
if (short.TryParse(fieldToken.ToString(), out short shortVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.Fixed32, writer);
ProtoWriter.WriteInt16(shortVal, writer);
}
else
{
exType = "short";
}
break;
case "date":
ProtoWriter.WriteFieldHeader(i, WireType.String, writer);
var dateToken = ProtoWriter.StartSubItem(fieldToken, writer);
if (int.TryParse(fieldToken.ToString(), out int dateVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.Variant, writer);
ProtoWriter.WriteInt32(dateVal, writer);
}
else
{
exType = "date";
}
ProtoWriter.EndSubItem(dateToken, writer);
break;
case "datetime":
if (fieldToken.Type == JTokenType.Date)
{
ProtoWriter.WriteFieldHeader(i, WireType.String, writer);
BclHelpers.WriteDateTime((DateTime)fieldToken, writer);
}
else
{
exType = "DateTime";
}
break;
case "guid":
if (Guid.TryParse(fieldToken.ToString(), out Guid guidVal))
{
ProtoWriter.WriteFieldHeader(i, WireType.String, writer);
BclHelpers.WriteGuid(guidVal, writer);
}
else
{
exType = "guid";
}
break;
case "char":
case "string":
default:
if (field.FieldType.StartsWith("["))
{
ProtoWriter.WriteFieldHeader(i, WireType.String, writer);
var token = ProtoWriter.StartSubItem(fieldToken, writer);
ProtoSerializer(writer, fieldToken as JObject, JsonConvert.DeserializeObject<List<CollectionFieldType>>(field.FieldType), name);
ProtoWriter.EndSubItem(token, writer);
}
else
{
ProtoWriter.WriteFieldHeader(i, WireType.String, writer);
ProtoWriter.WriteString(fieldToken.ToString(), writer);
}
break;
}
return exType;
}
不,基本上。 由於 protobuf(二進制格式)不明確,並且沒有關於如何解釋字段(它從類型和其他元數據中獲取)的附加上下文,因此不可能可靠地反序列化數據。 即使像字符串和整數這樣簡單的東西也很容易與多種類型混淆。 此外,在 protobuf 級別,沒有日期/時間作為原語的概念。
要明白我的意思:從上面的內容中獲取二進制有效負載並將其扔到https://protogen.marcgravell.com/decode - 由於存在多種可能性,它必須為您提供大多數類型的多種解釋。 它為您提供的選項集並不詳盡。
您可以使用SomeDTO
反序列SomeDTO
,然后使用您選擇的任何 JSON 序列化程序將其序列化為 JSON,但是:您需要具體類型。 我已經考慮使用 .proto 模式和閱讀器添加選項來做到這一點,但這並沒有真正改變你需要的東西——它只是改變了它的形狀。
如果您知道布局但沒有類型,則有選項,但此時僅創建類型會更容易。
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