Problem Statement/Rationale

Due to SERVER-77374, mongodump might dump an unversioned 2dsphereIndex on a time-series collection. Mongorestore treats unversioned 2dsphereIndexes as legacy indexes and thus always attempts to create them as v1. Attempting to restore a v1 2dshpereIndex causes mongorestore to fail with an error like the one below:

Failed: test.timeseries_geonear_measurements_indexed: error creating indexes for test.timeseries_geonear_measurements_indexed: createIndex error: (CannotCreateIndex) Error in specification { name: "loc_2dsphere", 2dsphereIndexVersion: 1, key: { data.loc: "2dsphere_bucket" }, originalSpec: { key: { loc: "2dsphere" }, name: "loc_2dsphere", 2dsphereIndexVersion: 1, v: 2 }, v: 2 } :: caused by :: unsupported geo index version { 2dsphereIndexVersion : 2dsphereIndexVersion: 1 }, only versions: [3] are supported

Steps to Reproduce

1. Create a time-series collection with 2dsphereIndex
2. Use mongodump to dump the collection
3. Run mongorestore to restore the collection with the 2dsphereIndex

Expected Results

Index restored with correct version.

Actual Results

Mongorestore failure.

Additional Notes

Discovered in passthrough test (link).