pymongo如何通过oplog获取数据(mongodb)

from pymongo import MongoClient
client = MongoClient('mongodb://source_server_address')
oplog = client.local.oplog.rs
last_timestamp = None
for entry in oplog.find().sort('$natural', -1).limit(1):
    last_timestamp = entry['ts']

target_client = MongoClient('mongodb://target_server_address')
while True:
    # 查询从上次读取时间戳之后的新条目
    new_entries = oplog.find({'ts': {'$gt': last_timestamp}})
    for entry in new_entries:
        # 根据 oplog 条目操作来更新目标服务器
        db_name = entry['ns'].split('.')[0]
        coll_name = entry['ns'].split('.')[1]
        collection = target_client[db_name][coll_name]
        operation = entry['op']
        if operation == 'i':
            collection.insert_one(entry['o'])
        elif operation == 'u':
            collection.update_one(entry['o2'], {'$set': entry['o']})
        elif operation == 'd':
            collection.delete_one(entry['o'])
        # 更新 last_timestamp 为当前处理的 oplog 条目的时间戳
        last_timestamp = entry['ts']

 from pymongo import MongoClient
 # 连接到 MongoDB 实例
 client = MongoClient('mongodb://your_mongodb_address')
 # 访问 oplog.rs 集合
 oplog = client.local.oplog.rs
 # 查询最新的 oplog 条目
 latest_entry = oplog.find().sort('$natural', -1).limit(1).next()
 print(latest_entry)