我正在学习Connecting to Cloud SQL with Cloud Functions教程，但我的Cloud Function无法连接到PostgreSQL数据库。
下面是我的函数代码：

import sqlalchemy

connection_name = "redacted-1234a:asia-northeast3:myinstance2"

query_string =  dict({"unix_sock": "/cloudsql/{}/.s.PGSQL.5432".format(connection_name)})

def insert(request):
    print(f"Started function - query_string: {query_string}")
    request_json = request.get_json()
    stmt = sqlalchemy.text('insert into {} {} values {}'.format("entries", "(guestName, content)", "('cloud hello', 'Got here!')"))
    
    db = sqlalchemy.create_engine(
      sqlalchemy.engine.url.URL(
        drivername="postgres+pg8000",
        username="postgres",
        password=redacted,
        database="guestbook",
        query=query_string,
      ),
      pool_size=5,
      max_overflow=2,
      pool_timeout=30,
      pool_recycle=1800
    )
    print("Created engine")
    try:
        with db.connect() as conn:
            print("Connected to engine")
            conn.execute(stmt)
    except Exception as e:
        return 'Error: {}'.format(str(e))
    return 'ok'

字符串
当我从“测试”选项卡运行它时，我得到：

2023-12-20 10:58:06.728 JST - Started function - query_string: {'unix_sock': '/cloudsql/nownow-8907a:asia-northeast3:myinstance2/.s.PGSQL.5432'}
2023-12-20 10:58:09.054 JST - Created engine
Error: (pg8000.core.InterfaceError) ('communication error', FileNotFoundError(2, 'No such file or directory'))
(Background on this error at: http://sqlalche.me/e/rvf5)

型
以下是我在设置数据库时在Cloud Shell中运行的内容：

$ gcloud sql connect myinstance2 --user=postgres
Allowlisting your IP for incoming connection for 5 minutes...done.                                                                                                                                      
Connecting to database with SQL user [postgres].Password: # typed in redacted
psql (16.1 (Debian 16.1-1.pgdg110+1), server 15.4)
SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384, compression: off)
Type "help" for help.
postgres=> CREATE DATABASE guestbook;
\CREATE DATABASE
postgres=> \connect guestbook;
Password: # typed in redacted
psql (16.1 (Debian 16.1-1.pgdg110+1), server 15.4)
SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384, compression: off)
You are now connected to database "guestbook" as user "postgres".
guestbook=> CREATE TABLE entries (guestName VARCHAR(255), content VARCHAR(255), entryID SERIAL PRIMARY KEY);
CREATE TABLE

型
我怎么才能让它工作呢？我觉得我已经检查了所有的东西：

• 该函数使用具有Cloud SQL Client角色的服务帐户运行
• redacted是postgres本身和数据库的密码（我可以通过Cloud Shell使用它进行连接）
• PostgreSQL示例同时具有公网IP和私有IP，并启用了“私有路径”
• SQL > Connections > Security将Google Cloud Services授权和App Engine授权设置为“Enabled”，并将“Allow only SSL connections”和“Require trusted client certificates”设置为“Disabled”。

云函数的另一个有趣的异常是，我在创建过程中验证了3次“允许未经身份验证的调用”被选中，但在创建函数后，它又回到了“需要身份验证”。我不认为这是超级相关的，因为我仍然能够 * 运行 * 函数，我只是不能连接到数据库。