Django系统检查、迁移和测试在本地通过，但在Docker CI/CD环境中失败

Question

问题

老实说，我只是把这件事搞砸了，因为在问这个问题之前，我已经用尽了所有可能的途径。我不知道这里有什么问题。

我有一个Django应用程序，它可以很好地在本地运行。我可以进行迁移。我已经在本地开发了这方面的详细内容，并且在模型、测试或任何特性方面都没有任何问题。

这里的问题是，第二次使用GitLab的CI/CD Runner并执行与我在本地执行的步骤完全相同的步骤，我就得到了这个输出。

ERRORS:
piano_gym_api.LearnerEnrolledLesson.enrolled_course: (fields.E300) Field defines a relation with model 'piano_gym_api.LearnerEnrolledCourse', which is either not installed, or is abstract.
piano_gym_api.LearnerEnrolledLesson.enrolled_course: (fields.E307) The field piano_gym_api.LearnerEnrolledLesson.enrolled_course was declared with a lazy reference to 'piano_gym_api.learnerenrolledcourse', but app 'piano_gym_api' doesn't provide model 'learnerenrolledcourse'.
piano_gym_api.LearnerEnrolledLesson.enrolled_school: (fields.E300) Field defines a relation with model 'piano_gym_api.LearnerEnrolledSchool', which is either not installed, or is abstract.
piano_gym_api.LearnerEnrolledLesson.enrolled_school: (fields.E307) The field piano_gym_api.LearnerEnrolledLesson.enrolled_school was declared with a lazy reference to 'piano_gym_api.learnerenrolledschool', but app 'piano_gym_api' doesn't provide model 'learnerenrolledschool'.

环境

我在Django 2.2中使用Python3.7。我的依赖关系如下所示：

certifi==2019.3.9
chardet==3.0.4
coreapi==2.3.3
coreschema==0.0.4
Django==2.2
django-cors-headers==3.0.2
django-extensions==2.1.7
djangorestframework==3.9.4
djangorestframework-jwt==1.11.0
gunicorn==19.9.0
idna==2.8
itypes==1.1.0
Jinja2==2.10.1
lxml==4.3.3
MarkupSafe==1.1.1
music21==5.5.0
PyJWT==1.7.1
pytz==2019.1
requests==2.22.0
six==1.12.0
sqlparse==0.3.0
uritemplate==3.0.0
urllib3==1.25.3
whitenoise==4.1.2

我使用的是免费版本的GitLab和GitLab Runner。

这是一个简单的django项目。有一个项目和一个应用程序。

我的settings.conf的INSTALLED_APPS看起来像这样

# Application definition
INSTALLED_APPS = [
    # Django Default
    "django.contrib.admin",
    "django.contrib.auth",
    "django.contrib.contenttypes",
    "django.contrib.sessions",
    "django.contrib.messages",
    "django.contrib.staticfiles",
    # Third-Party Apps
    "corsheaders",
    "django_extensions",
    "rest_framework",
    "rest_framework.authtoken",
    "whitenoise.runserver_nostatic",
    # Custom Apps
    "piano_gym_api",
]

本地运行的步骤

这将使通过

• pip3 install virtualenv
• virtualenv -p python3 venv
• source venv/bin/activate
• pip3 install -r requirements.txt
• python3 manage.py makemigrations piano_gym_api
• python3 manage.py migrate
• python3 manage.py test

在GitLab CI/CD中运行的步骤

这将使失败

我安装了GitLab Runner

我在根目录中创建了一个.gitlab-ci.yml文件。它所拥有的只是：

stages:
  - test

api-test:
  stage: test
  image: python:3.7
  script:
    - cd piano_gym_back_end
    # Create environment for python
    - pip3 install virtualenv
    - virtualenv -p python3 venv
    - source venv/bin/activate
    - pip3 install -r requirements.txt
    # Set up and run tests
    - python3 manage.py makemigrations piano_gym_api
    - python3 manage.py migrate
    - python3 manage.py test

然后提交分支上的所有内容并运行gitlab-runner exec docker api-test。

然后遍历每一件事情并输出

$ python3 manage.py makemigrations piano_gym_api
SystemCheckError: System check identified some issues:

ERRORS:
piano_gym_api.LearnerEnrolledLesson.enrolled_course: (fields.E300) Field defines a relation with model 'piano_gym_api.LearnerEnrolledCourse', which is either not installed, or is abstract.
piano_gym_api.LearnerEnrolledLesson.enrolled_course: (fields.E307) The field piano_gym_api.LearnerEnrolledLesson.enrolled_course was declared with a lazy reference to 'piano_gym_api.learnerenrolledcourse', but app 'piano_gym_api' doesn't provide model 'learnerenrolledcourse'.
piano_gym_api.LearnerEnrolledLesson.enrolled_school: (fields.E300) Field defines a relation with model 'piano_gym_api.LearnerEnrolledSchool', which is either not installed, or is abstract.
piano_gym_api.LearnerEnrolledLesson.enrolled_school: (fields.E307) The field piano_gym_api.LearnerEnrolledLesson.enrolled_school was declared with a lazy reference to 'piano_gym_api.learnerenrolledschool', but app 'piano_gym_api' doesn't provide model 'learnerenrolledschool'.
ERROR: Job failed: exit code 1
FATAL: exit code 1                      

模型

现在我明白了，这是说它在piano_gym_api应用程序中找不到模型。但这没有道理。

这里的模式是：

class LearnerEnrolledLesson(Model):
    is_enrolled = BooleanField(default=True)
    learner = ForeignKey("piano_gym_api.Learner", on_delete=CASCADE)
    # ---
    enrolled_school = ForeignKey("piano_gym_api.LearnerEnrolledSchool", on_delete=CASCADE)
    enrolled_course = ForeignKey("piano_gym_api.LearnerEnrolledCourse", on_delete=CASCADE)
    # ---
    school = ForeignKey(School, on_delete=CASCADE)
    course = ForeignKey(SchoolCourse, on_delete=CASCADE)
    lesson = ForeignKey(SchoolLesson, on_delete=CASCADE)
    order = IntegerField(default=1)

    REQUIRED_FIELDS = ["learner", "school", "course", "lesson", "enrolled_school", "enrolled_course"]

    objects = LearnerEnrolledLessonManager()

    class Meta:
        ordering = ("order",)
        unique_together = ("learner", "school", "course", "lesson", "enrolled_school", "enrolled_course", "order")

我在这里所做的唯一事情就是使用字符串来引用piano_gym_api.LearnerEnrolledSchool和piano_gym_api.LearnerEnrolledCourse。

之所以这样做，是因为这些模型有一个返回LearnerEnrolledLesson的函数，这是一个循环依赖关系，所以我必须引用模型而不使用导入路径。

求助呼吁

我不知道为什么这是失败在我的CI/CD对接环境。我没做什么不同的事。我的settings.py在开发环境和ci/cd环境之间没有变化。步骤是完全一样的。

我在这里可能做错了什么？

Answer 1

我找到了解决这个问题的方法，这是非常微妙的。

首先，我要感谢来自Python不和谐频道的一个名为Python不和谐频道的人。多亏了他们的努力，他们和我一起坐下来，走过了我所经历的一切，我们才能诊断出这一点。

这里的问题很微妙，因为在sqlite3中没有任何问题。然而，当我迁移到postgresql时，问题就出现了。

具体的问题是，我没有制造它，所以我的模型是可用的。

Django需要在路径中存在模型

• django_project_name/django_app_name/models.py

或

• django_project_name/django_app_name/models/

我的目录结构实际上如下所示

├── requirements.txt
├── manage.py
├── django_app_name
│   ├── models
│   │   └── __init__.py
│   ├── urls.py
│   └── versions
│       ├── __init__.py
│       └── v1
│           ├── __init__.py
│           ├── models
│           │   ├── __init__.py
│           │   └── ...
│           └── views
│               ├── __init__.py
│               └── ...
└── django_project_name
    └── ...

这里的问题是，为了创建一个版本化的目录结构，我将模型移动到django_project_name/django_app_name/versions/v1/中。

由于这个原因，Django找不到模型，因为我没有通过models.py文件或Django应用程序中期望的models目录显式地提供它们。

这就是为什么我会得到这样的错误: Django无法找到特定的模型，尽管它们在那里。

要修复这个解决方案，我必须在django_project_name/django_app_name/models/__init__.py文件中导出它们的引用，从而显式地公开它们。

看起来是这样的：

# REQUIRED!!!
# Django requires models that are being used to be exposed in this models
# directory
# Because we have opted to use the `versions` folder for storing the structure
# of our project, that means we need to surface those models explicitly here in
# order to remove the possibility of a missing model during the `makemigrations`
# and `migrate` commands
from django_app_name.versions.v1.models.example_model_one import *
from django_app_name.versions.v1.models.example_model_two import *
from django_app_name.versions.v1.models.example_model_three import *
...

有了这个，我就能让我的模型可以用于makemigrations和migrate。

非常微妙:)