python - Flask：如何在路由（其他 .py 文件）的 __init.py__.create_app() 中使用创建一次的 cx_Oracle.SessionPool

Question

我有一个像这样的简单 Flask 应用程序：

simple_app/lib/oracle.py：

import cx_Oracle
from flask import current_app

def create_pool():
    # Create session pool
    pool = cx_Oracle.SessionPool(user=current_app.config['USER'],
                                 password=current_app.config['PASSWD'],
                                 dsn=current_app.config['DSN'],
                                 min=4,
                                 max=10,
                                 increment=1,
                                 threaded=True,
                                 getmode=cx_Oracle.SPOOL_ATTRVAL_WAIT)
    return pool

simple_app/routes/ init .py：

from .hello import hello_bp
from .oracle_pdb_backup import oracle_pdb_backup_bp

def init_app(app):
    app.register_blueprint(hello_bp)
    app.register_blueprint(oracle_pdb_backup_bp)

simple_app/routes/hello.py：

from flask import Blueprint, jsonify

hello_bp = Blueprint('hello', __name__)

@hello_bp.route('/hello', methods=['GET'])
def hello_get():
    return jsonify(message = f'hello world!'), 200

simple_app/routes/oracle_pdb_backup.py：

from flask import Blueprint, jsonify
from ..lib.oracle import *

oracle_pdb_backup_bp = Blueprint('oracle_pdb_backup', __name__)

@oracle_pdb_backup_bp.route('/oracle/pdb/backup', methods=['GET'])
def oracle_pdb_backup_post():

    pool = ?????? how to access pool defined at app creation ??????
    # Acquire a connection from the pool
    connection = pool.acquire()
    # Use the pooled connection
    cursor = connection.cursor()
    cursor.execute('select * from dual')
    result = cursor.fetchall()
    cursor.close()
    # Release the connection to the pool
    db_pool.release(connection)
    return jsonify(message = result), 200

简单应用程序/初始化.py：

from flask import Flask
from flask_cors import CORS

from .lib.oracle import *
from .routes import *

def create_app():
    app = Flask(__name__)
    CORS(app)
    app.secret_key = 'dev'
    app.config.from_object('configSIMPLE')

    with app.app_context():
       create_pool()
    routes.init_app(app)
    return app

我使用以下命令启动应用程序：

export PATH=~/python3/bin:$PATH
export LD_LIBRARY_PATH=~/instantclient_19_12
cd ~/myapps
export FLASK_RUN_HOST=`hostname`
export FLASK_RUN_PORT=8080
export FLASK_APP=simple_app
export FLASK_ENV=development
export FLASK_DEBUG=1
flask run 

如何在 create_app() 中创建一次 cx_Oracle.SessionPool 并在我的所有路由中使用它

注意：池是在 simple_app/lib/oracle.py 的 create_pool() 函数中创建的

首先，我不知道是否：

with app.app_context():
   create_pool()

是在创建应用程序时初始化池的正确方法吗？

其次，如何在我的路线中使用创建的池？

请参阅 simple_app/routes/oracle_pdb_backup.py 中的以下行：

pool = ?????? how to access pool defined at app creation ??????

你能告诉我我应该修改什么以使其工作吗？

感谢您的投入

标签： pythonflaskdatabase-connectioncx-oracle