pip install pymongo

from pymongo import MongoClient
from pymongo.errors import ConnectionFailure, OperationFailure

# Connection URI (Replace with your actual connection information)
uri = "mongodb://mongouser:thepasswordA1@10.66.187.127:27017/admin"

# Replica set connection string (Recommended, supports automatic failover):
# uri = "mongodb://mongouser:thepasswordA1@10.66.187.127:27017,10.66.187.128:27017,10.66.187.129:27017/admin?replicaSet=cmgo-xxxxxxxx_0"

try:
    # Create a client connection (Includes connection pool configuration)
    client = MongoClient(
        uri,
        maxPoolSize=50,           # Maximum size of the connection pool
        minPoolSize=5,            # Minimum size of the connection pool
        connectTimeoutMS=10000,   # Connection timeout of 10 seconds
        socketTimeoutMS=30000,    # Socket timeout of 30 seconds
        retryWrites=True,         # Enable retryable writes
        retryReads=True,          # Enable retryable reads
        w="majority"              # Write concern level
    )

    # Verify whether the connection is successful.
    client.admin.command("ping")
    print("Connection successful")

except ConnectionFailure as e:
    print(f"Connection failure: {e}")
    raise

from pymongo import MongoClient
from pymongo.errors import ConnectionFailure, OperationFailure
from bson.objectid import ObjectId
from datetime import datetime

def main():
    uri = "mongodb://mongouser:thepasswordA1@10.66.187.127:27017/admin"

    try:
        client = MongoClient(uri, retryWrites=True, w="majority")
        client.admin.command("ping")
        print("Connection successful")

        # Select a database and a collection
        db = client["mydb"]
        collection = db["users"]

        # ========== Insert a Document ==========
        # Insert a single document
        doc = {
            "username": "jack",
            "age": 31,
            "email": "jack@example.com",
            "created_at": datetime.now()
        }
        result = collection.insert_one(doc)
        print(f"Inserted document ID: {result.inserted_id}")

        # Batch Insert Documents
        docs = [
            {"username": "alice", "age": 28, "email": "alice@example.com"},
            {"username": "bob", "age": 35, "email": "bob@example.com"},
        ]
        result = collection.insert_many(docs)
        print(f"Batch inserted {len(result.inserted_ids)} documents")

        # ========== Query Documents ==========
        # Query a Single Document
        user = collection.find_one({"username": "jack"})
        print(f"Query a single document: {user}")

        # Conditional Query (Age greater than 30)
        cursor = collection.find({"age": {"$gt": 30}})
        print("Users with age greater than 30:")
        for doc in cursor:
            print(f"  - {doc['username']}, Age: {doc['age']}")

        # ========== Update Documents ==========
        result = collection.update_one(
            {"username": "jack"},
            {"$set": {"age": 32, "updated_at": datetime.now()}}
        )
        print(f"Updated {result.modified_count} documents")

        # ========== Delete Documents ==========
        result = collection.delete_many({"username": {"$in": ["jack", "alice", "bob"]}})
        print(f"Deleted {result.deleted_count} documents")

    except ConnectionFailure as e:
        print(f"Connection failure: {e}")
    except OperationFailure as e:
        print(f"Operation failed: {e}")
    finally:
        client.close()
        print("Connection closed")

if __name__ == "__main__":
    main()

Connection successful
Inserted document ID: 6789abcdef1234567890abcd
Batch Insert 2 Documents
Query a single document: {'_id': ObjectId('6789abcdef1234567890abcd'), 'username': 'jack', 'age': 31, 'email': 'jack@example.com', 'created_at': datetime.datetime(2026, 4, 17, -1, 0, 0)}
Users with age greater than 30:
  - jack, age: 31
  - bob, age: 35
Update 1 Document
Delete 3 Documents
The connection has been closed.

from pymongo import MongoClient, ReadPreference

client = MongoClient(
    "mongodb://mongouser:thepasswordA1@IP1:27017,IP2:27017,IP3:27017/admin?replicaSet=cmgo-xxxxxxxx_0",
    readPreference="secondaryPreferred"
)

# Or specify at the collection level.
db = client["mydb"]
collection = db.get_collection("users", read_preference=ReadPreference.SECONDARY_PREFERRED)

pymongo.errors.OperationFailure: Authentication failed., full error: {'ok': 0.0, 'errmsg': 'Authentication failed.', 'code': 18, 'codeName': 'AuthenticationFailed'}

pymongo.errors.ServerSelectionTimeoutError: 10.66.187.127:27017: [Errno 110] Connection timed out, Timeout: 30s

pymongo.errors.AutoReconnect: connection was closed