在Mongo中存储Utc和本地日期时间

Question

我有一个Mongo C#实现,它将datetime存储为UTC.

MongoDB.Bson.Serialization.Options.DateTimeSerializationOptions options = 
    MongoDB.Bson.Serialization.Options.DateTimeSerializationOptions.UtcInstance;

var serializer = 
    new MongoDB.Bson.Serialization.Serializers.DateTimeSerializer(options);

MongoDB.Bson.Serialization.BsonSerializer.RegisterSerializer(
    typeof(DateTime),
    serializer);

我还需要将用户本地时区与UTC一起存储.为了解释,我有两个属性

DateTime WorkItemToCompleteBy{get; set;}
[BsonDateTimeOptions(Kind = DateTimeKind.Unspecified)]
DateTime WorkItemToCompleteByLocal{get; set;}

我想将澳大利亚/美国/印度/其他时间存储在本地属性中,并将相应的UTC值存储在另一个属性中.由于处理了几十个时区,我有代码将UTC转换为所需的时区并将其存储在WorkItemToCompleteByLocal属性中.我希望Mongo将这个值"按原样"存储并将其返回给我.问题是Mongo总是将它存储为ISODate并将值转换为Utc版本.解释.如果UTC是0730小时,我计算布里斯班时间为1730小时并将其设置为WorkitemToCompleteByLocal,它们将保存为

"WorkItemToCompleteBy" : ISODate("2013-06-05T07:30:00Z"),
"WorkItemToCompleteByLocal" : ISODate("2013-06-05T12:00:00Z"),

Mongo将提供的时间解释为本地,服务器位于印度,并将其转换为相当于1200小时的UTC.虽然它将值恢复为1730(IST虽然)但是它违背了我的目的并阻止我在Mongo上运行任何基于本地时间的查询.没有想法.感谢任何帮助,以帮助存储WorkItemToCompleteByLocal日期'原样'而无需修改

Answer 1

这是我强制MongoDB存储原始值的方法,并忽略DateTime对象中的DateTimeKind属性.

这可能不适用于您的业务逻辑,但出于我们的特殊原因对我们有意义.

BsonSerializer.RegisterSerializer(typeof(DateTime), new MyMongoDBDateTimeSerializer());


public class MyMongoDBDateTimeSerializer : DateTimeSerializer
{
    //  MongoDB returns datetime as DateTimeKind.Utc, which cann't be used in our timezone conversion logic
    //  We overwrite it to be DateTimeKind.Unspecified
    public override object Deserialize(MongoDB.Bson.IO.BsonReader bsonReader, System.Type nominalType, MongoDB.Bson.Serialization.IBsonSerializationOptions options)
    {
        var obj = base.Deserialize(bsonReader, nominalType, options);
        var dt = (DateTime) obj;
        return new DateTime(dt.Ticks, DateTimeKind.Unspecified);
    }

    //  MongoDB returns datetime as DateTimeKind.Utc, which cann't be used in our timezone conversion logic
    //  We overwrite it to be DateTimeKind.Unspecified
    public override object Deserialize(MongoDB.Bson.IO.BsonReader bsonReader, Type nominalType, Type actualType, MongoDB.Bson.Serialization.IBsonSerializationOptions options)
    {
        var obj = base.Deserialize(bsonReader, nominalType, actualType, options);
        var dt = (DateTime)obj;
        return new DateTime(dt.Ticks, DateTimeKind.Unspecified);
    }

    //  MongoDB stores all datetime as Utc, any datetime value DateTimeKind is not DateTimeKind.Utc, will be converted to Utc first
    //  We overwrite it to be DateTimeKind.Utc, becasue we want to preserve the raw value
    public override void Serialize(MongoDB.Bson.IO.BsonWriter bsonWriter, System.Type nominalType, object value, MongoDB.Bson.Serialization.IBsonSerializationOptions options)
    {
        var dt = (DateTime) value;
        var utcValue = new DateTime(dt.Ticks, DateTimeKind.Utc);
        base.Serialize(bsonWriter, nominalType, utcValue, options);
    }
}

Answer 2

新版C#driver =>

    public class MyMongoDBDateTimeSerializer : DateTimeSerializer
{
    //  MongoDB returns datetime as DateTimeKind.Utc, which cann't be used in our timezone conversion logic
    //  We overwrite it to be DateTimeKind.Unspecified
    public override DateTime Deserialize(BsonDeserializationContext context, BsonDeserializationArgs args)
    {
        var obj = base.Deserialize(context, args);
        return new DateTime(obj.Ticks, DateTimeKind.Unspecified);
    }

    //  MongoDB stores all datetime as Utc, any datetime value DateTimeKind is not DateTimeKind.Utc, will be converted to Utc first
    //  We overwrite it to be DateTimeKind.Utc, becasue we want to preserve the raw value
    public override void Serialize(BsonSerializationContext context, BsonSerializationArgs args, DateTime value)
    {
        var utcValue = new DateTime(value.Ticks, DateTimeKind.Utc);
        base.Serialize(context, args, utcValue);
    }
}

Answer 3

在 .net 驱动程序版本 2.4 中，使用以下命令：

using MongoDB.Bson.Serialization;
using MongoDB.Bson.Serialization.Serializers;

BsonSerializer.RegisterSerializer(DateTimeSerializer.LocalInstance);

这样日期时间值将在 db 中使用 kind=utc 存储，但在本地种类中反序列化。