{
"candidate_servers": [],
"eligible_servers": [],
"in_latency_window": [],
"operation": "read",
"read_preference": {
"mode": "SecondaryPreferred",
"tags": [
{
"data_center": "nyc"
}
]
},
"suitable_servers": [],
"topology_description": {
"servers": [],
"type": "Unknown"
}
}