我尝试了官方gitlab文档中解释的方式，在主机上配置数据库并尝试与DB_HOST=postgres连接。但是psycopg抛出错误：(psycopg.OperationalError) connection is bad: Name or service not known. My .gitlab-ci.yml：

image: python:3.11

default:
  services:
    - postgres:15.1

before_script:
  - python3.11 --version
  - pip3.11 --version
  - echo "hello world"

build-python:
  stage: build
  script:
    - echo "this is test job"
    - cd backend
    - pip3.11 install virtualenv
    - virtualenv venv
    - source venv/bin/activate
    - pip3.11 install -r requirements.txt
    - echo "ended building python test job"
    - alembic revision --autogenerate -m "migrating"
    - alembic upgrade head

字符串
Alembic.ini文件从我试图访问数据库：

# A generic, single database configuration.

[alembic]
# path to migration scripts
script_location = migrations

prepend_sys_path = .

version_path_separator = os  # Use os.pathsep. Default configuration used for new projects.

sqlalchemy.url = driver://user:pass@localhost/dbname

[post_write_hooks]

[loggers]
keys = root,sqlalchemy,alembic

[handlers]
keys = console

[formatters]
keys = generic

[logger_root]
level = WARN
handlers = console
qualname =

[logger_sqlalchemy]
level = WARN
handlers =
qualname = sqlalchemy.engine

[logger_alembic]
level = INFO
handlers =
qualname = alembic

[handler_console]
class = StreamHandler
args = (sys.stderr,)
level = NOTSET
formatter = generic

[formatter_generic]
format = %(levelname)-5.5s [%(name)s] %(message)s
datefmt = %H:%M:%S

型
sqlalchemy.url在env.py中定义

config.set_main_option('sqlalchemy.url', DATABASE_URL)

型
DATABASE_URL：

DATABASE_URL = f'postgresql+psycopg://{DB_USER}:{DB_PASSWORD}@{DB_HOST}:{DB_PORT}/{DB_NAME}'

型
我错过了什么？谢谢你的帮助。