pyMongoDB 基础使用模版

Posted 2021-06-19 我超怕的

pyMongoDB基础使用 - https://www.cnblogs.com/iAmSoScArEd/p/14903131.html -我超怕的

当不知道MongoDB中有什么数据库时可使用以下函数查询所有数据库：

print(client.database_names()) 

当不知道MongoDB中有什么集合时可使用一下函数获取所有集合

print(db.collection_names()) 

from pymongo.mongo_client import MongoClient
from pymongo import ReadPreference


\'\'\'Connect the mongoDB\'\'\'
def get_mongo_conn(host, port, user, password, usedatabse):
    db = None
    client = None
    try:
        client = MongoClient(host, port,maxPoolSize=500, connectTimeoutMS=10000,serverSelectionTimeoutMS=5000)
        # print(client.database_names()) 获取所有数据库
        db = client.get_database(usedatabse,read_preference=ReadPreference.SECONDARY)
        
        if db.authenticate(user, password):
            # print(\'认证成功！\')
            # print(db.collection_names()) 获取所有集合
            pass
        else:
            print(\'认证失败！\')
    except Exception as ex:
        print("connection Mongo exception: %s" % ex.message)
    return db, client

# settings
def get_mongo_config():
    return {
        \'host\' : \'127.0.0.1\',
        \'port\' : 27000,
        \'dbName\' : \'1234\',
        \'userName\' : \'username\',
        \'password\' : \'password\',
        \'collectionName\' : \'collection\'
    }

# define function to query one row
def query_one(queryDict={}):
    # return dict
    gmc = get_mongo_config()
    host = gmc[\'host\']
    port = gmc[\'port\']
    dbName = gmc[\'dbName\']
    userName = gmc[\'userName\']
    password = gmc[\'password\']
    collectionName = gmc[\'collectionName\']
    db,client = get_mongo_conn(host,port,userName,password,dbName)
    if db is None or client is None:
        print(\'获取mongo连接失败！\')
        return None
    collection = db[collectionName]
    return collection.find_one()

# define function to query more rows
def query_all(queryDict,limit):
    # return list
    gmc = get_mongo_config()
    host = gmc[\'host\']
    port = gmc[\'port\']
    dbName = gmc[\'dbName\']
    userName = gmc[\'userName\']
    password = gmc[\'password\']
    collectionName = gmc[\'collectionName\']
    db,client = get_mongo_conn(host,port,userName,password,dbName)
    if db is None or client is None:
        print(\'获取mongo连接失败！\')
        return None
    collection = db[collectionName]
    return collection.find(queryDict).limit(limit)

def run(device=\'\'):
    queryDict = {}
    results = query_all(queryDict,5) # query 5 rows
    for rs in results:
        print(rs)

run()