mongodb golang按日期限制结果

Question

I have a mongodb collection that I am trying to limit the result set, but the data was created by someone else and the date format appears to be stored as "2016-05-12 00:00:00.000Z". I am unsure how to format my find query to limit this type of date. I have been successful with other types of date formats, but not this one. Has anyone else encountered this issue?

myCollection {
  "_id" : {
    "$oid" : bson.ObjectId
  },
  "createdDate" : {
    "$date" : Date
} 

This is what I have attempted.

toDate := time.Date(time.Now().Year(), time.Now().Month(), time.Now().Day(), 0, 0, 0, 0, time.UTC)
fromDate := toDate.AddDate(0, 0, -1)

collectionResult := collectionRecords.Find(bson.M{"retailer": result.Id, "createdAt": bson.M{"$gte": fromDate}})

Ultimately, I would like to limit to one day and was attempting to do the following:

collectionResult := collectionRecords.Find(bson.M{"retailer": result.Id, "createdAt": bson.M{"$gte": fromDate, "$lt": toDate}})
collectionResult.All(&collectionData)
collectionCount, _ := collectionResult.Count()
fmt.Println("Count: ", collectionCount)

it always returns 0. Like I stated above I have been successful with UTC dates, but this one seems to trouble me.

Answer 1

If I understand the question, you're looking how to create a UTC timestamp 24 hours into the past where hours have been truncated?

You can try filtering on these dates:

package main

import (
    "fmt"
    "time"
)

func main() {
    today := time.Now().Truncate(24*time.Hour).UTC()
    yesterday := today.Add(-24*time.Hour)
    fmt.Println(today)
    fmt.Println(yesterday)
}