Get MongoDB collection stats

mongodb-stats.js

db.getCollectionNames().forEach(function (collectionName) {
    const collection = db.getCollection(collectionName);
    const stats = collection.stats();
    print('COLLECTION:           ' + collectionName);
    print('  size(MB):           ' + (stats.size/1024/1024).toFixed(2));
    print('  count:              ' + stats.count);
    print('  avgObjSize:         ' + stats.avgObjSize);
    print('  storageSize(MB):    ' + (stats.storageSize/1024/1024).toFixed(2));
    print('  nindexes:           ' + stats.nindexes);
    print('  totalIndexSize(MB): ' + (stats.totalIndexSize/1024/1024).toFixed(2));
    // per-index stats
    const indexStats = collection.aggregate([{$indexStats:{}}]);
    indexStats.forEach(function (indexStat) {
        print('INDEX:                ' + indexStat.name);
        print('  size(MB):           ' + (stats.indexSizes[indexStat.name]/1024/1024).toFixed(2));
        print('  accesses:           ' + indexStat.accesses.ops);
        print('  since:              ' + indexStat.accesses.since.toISOString());
    });
    print('--------------------------------------------------');
});