I encountered with “unrecognized time zone identifier” error when working with some timezones in MongoDB 4.4, such as the Etc/UTC timezone.
Example query:
> db.data.insert({ dt: new ISODate() })
WriteResult({ "nInserted" : 1 })
> db.data.aggregate([
... {
... "$project": {
... "dtTimezone": {
... "$dateToString": {
... "date": "$dt",
... "timezone": "Etc/UTC"
... }
... }
... }
... }
... ])
uncaught exception: Error: command failed: {
"ok" : 0,
"errmsg" : "PlanExecutor error during aggregation :: caused by :: unrecognized time zone identifier: \"Etc/UTC\"",
"code" : 40485,
"codeName" : "Location40485"
} with original command request: {
"aggregate" : "data",
"pipeline" : [
{
"$project" : {
"dtTimezone" : {
"$dateToString" : {
"date" : "$dt",
"timezone" : "Etc/UTC"
}
}
}
}
],
"cursor" : {
},
"lsid" : {
"id" : UUID("24a0ca58-6d03-4827-b59c-4bd82ddf9976")
}
} on connection: connection to 127.0.0.1:27017 : aggregate failed :
_getErrorWithCode@src/mongo/shell/utils.js:25:13
doassert@src/mongo/shell/assert.js:18:14
_assertCommandWorked@src/mongo/shell/assert.js:719:17
assert.commandWorked@src/mongo/shell/assert.js:811:16
DB.prototype._runAggregate@src/mongo/shell/db.js:276:5
DBCollection.prototype.aggregate@src/mongo/shell/collection.js:1058:12
@(shell):1:1
At the same time, a query for Europe/London timezone runs correctly:
> db.data.aggregate([
... {
... "$project": {
... "dtTimezone": {
... "$dateToString": {
... "date": "$dt",
... "timezone": "Europe/London"
... }
... }
... }
... }
... ])
{ "_id" : ObjectId("611832f076340952c425ce80"), "dtTimezone" : "2021-08-14T22:17:36.349Z" }
I tried to investigate the problem, and installed MongoDB 4.4 on a clean Ubuntu 20.04 and the problem still reproduces. The same problem occurs when using MongoDB 5.0.
There is a similar problem, the solution to which came down to commenting “processManagement.timeZoneInfo” option and using the internal timezone database. This really helps, queries using the internal timezone database run correctly.
The advice to copy the database from the documentation to another location and explicitly set it via --timeZoneInfo does not solve the problem either, requests with timezone Etc/UTC also end with an error.
I would be very grateful if someone could help me figure out why queries using external timezones database end up with an error. Seems like a bug or something. What could be the reason?