查询mongodb以获取最近30分钟内创建的文档

Question

I'm in Central European Summer Time (CEST) at 15:08 I added document to my collection. In model to new Schema I'm passing timestamps: true . Its createdAt is incorrect, it's two hours too early:

createdAt:2019-08-21 13:08:39.219

Why? Also what does .219 at the end mean? Lastly how can I query this collection to get every one which createdAt is within last 30 minutes?

const c = await Collection.find({
    createdAt: {
        $gte: new Date() // ???
    }
});

I've combined answers with comments and tried something like this:

const d = new Date(
    new Date().getTime() + new Date().getTimezoneOffset() * 60000 - 30 * 60000
);
const c = await Collection.find({
    createdAt: { $gte: d }
});

but it doesn't seem to work correctly. I execute this code at 15:47 CEST which is 13:47 UTC so earliest document should be from 13:17 but I get results with "createdAt": "2019-08-21T12:43:38.395Z", .

Answer 1

You can create a date that ignores your browser timezone:

function newDateTZSafe(){
    var now = new Date();
    return new Date(now.getTime() + now.getTimezoneOffset() * 60000);
}

or as alternative, if you heavily rely on dates, use moment.js

Answer 2

**Try this query**
const c = await Collection.find({
    createdAt: {
        "$gte" : new Date(ISODate().getTime() - 1000 * 60 * 30) }
    }
});