unable to connect to mssql database from Django app from a docker container

Question

I am new to docker containers and I have been struggling to connect to mssql database from Django app and successfully launch docker container for my rest API. Please bear with me for long question.

Here is my docker file

FROM ubuntu:19.04
ENV PYTHONUNBUFFERED 1
ENV DEBIAN_FRONTEND noninteractive

RUN apt-get update && apt-get install -y curl apt-transport-https python3 python3-pip python-dev locales
RUN apt-get -y update && apt-get install -y sudo apt-utils gnupg ca-certificates
RUN apt-get update && apt-get install -y git

RUN curl https://packages.microsoft.com/keys/microsoft.asc | apt-key add -
RUN curl https://packages.microsoft.com/config/ubuntu/19.04/prod.list > /etc/apt/sources.list.d/mssql-release.list

RUN apt-get update --fix-missing && ACCEPT_EULA=Y apt-get install -y msodbcsql17
# optional: for bcp and sqlcmd
RUN ACCEPT_EULA=Y apt-get install mssql-tools
RUN echo 'export PATH="$PATH:/opt/mssql-tools/bin"' >> ~/.bash_profile
RUN echo 'export PATH="$PATH:/opt/mssql-tools/bin"' >> ~/.bashrc

RUN /bin/bash -c "source ~/.bashrc"
# optional: for unixODBC development headers
RUN apt-get -y update && apt-get install -y unixodbc-dev

#RUN echo "en_US.UTF-8 UTF-8" > /etc/locale.gen
#RUN locale-gen

RUN git clone https://github.com/mushfiq/djmsc.git o ms_demo

WORKDIR ms_demo

RUN mkdir -p logs

RUN pip3 install -U pip

#RUN apt-get update && apt-get install -y uwsgi-plugin-python
#RUN apt-get update && apt-get install -y uwsgi

ENV PATH="/usr/local/lib/python3.7:/usr/local/lib/python3.7/dist-packages:${PATH}"

RUN pip3 install -r requirements.txt --trusted-host pypi.python.org --trusted-host files.pythonhosted.org --trusted-host pypi.org

EXPOSE 8000
CMD ["python3", "manage.py", "runserver", "0.0.0.0:8000"]

My requirements.txt file look like this

Django==2.1.8
pyodbc==4.0.26
django-mssql==1.8
django-pyodbc==1.1.3
django-pyodbc-azure==2.1.0.0
djangorestframework==3.9.2
docker==3.7.3
docker-compose==1.24.1
pymssql==2.1.4
sqlparse==0.3.0
SQLAlchemy==1.3.0
sql_server.pyodbc

And here is my DB setting from settings.py file from Django project

DATABASES = {
'default': {
    'ENGINE': 'sql_server.pyodbc',
    'NAME': 'MyTestDB',
    'USER': '',
    'PASSWORD': '',
    'HOST': 'myMSSQLDBHOST', # Or an IP Address that your DB is hosted on
    'PORT': '',
    'OPTIONS': {
        'provider': 'SQLOLEDB',
        'driver': 'SQL Server Native Client 11.0',
        'isolation_level': 'READ UNCOMMITTED',  # prevent SELECT deadlocks
    },
}

}

After the docker image build command is successful. When I try to run the image I get the following error.

> docker run -p 8000:8000 tanzeelbhatti/ms_demo
Unhandled exception in thread started by <function check_errors.<locals>.wrapper at 0x7f0f533a18c8>
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/django/utils/autoreload.py", line 225, in wrapper
    fn(*args, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/django/core/management/commands/runserver.py", line 109, in inner_run
    autoreload.raise_last_exception()
  File "/usr/local/lib/python3.7/dist-packages/django/utils/autoreload.py", line 248, in raise_last_exception
    raise _exception[1]
  File "/usr/local/lib/python3.7/dist-packages/django/core/management/__init__.py", line 337, in execute
    autoreload.check_errors(django.setup)()
  File "/usr/local/lib/python3.7/dist-packages/django/utils/autoreload.py", line 225, in wrapper
    fn(*args, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/django/__init__.py", line 24, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/usr/local/lib/python3.7/dist-packages/django/apps/registry.py", line 112, in populate
    app_config.import_models()
  File "/usr/local/lib/python3.7/dist-packages/django/apps/config.py", line 198, in import_models
    self.models_module = import_module(models_module_name)
  File "/usr/lib/python3.7/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
  File "<frozen importlib._bootstrap>", line 983, in _find_and_load
  File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 728, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/usr/local/lib/python3.7/dist-packages/django/contrib/auth/models.py", line 2, in <module>
    from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
  File "/usr/local/lib/python3.7/dist-packages/django/contrib/auth/base_user.py", line 47, in <module>
    class AbstractBaseUser(models.Model):
  File "/usr/local/lib/python3.7/dist-packages/django/db/models/base.py", line 101, in __new__
    new_class.add_to_class('_meta', Options(meta, app_label))
  File "/usr/local/lib/python3.7/dist-packages/django/db/models/base.py", line 305, in add_to_class
    value.contribute_to_class(cls, name)
  File "/usr/local/lib/python3.7/dist-packages/django/db/models/options.py", line 203, in contribute_to_class
    self.db_table = truncate_name(self.db_table, connection.ops.max_name_length())
  File "/usr/local/lib/python3.7/dist-packages/django/db/__init__.py", line 33, in __getattr__
    return getattr(connections[DEFAULT_DB_ALIAS], item)
  File "/usr/local/lib/python3.7/dist-packages/django/db/utils.py", line 202, in __getitem__
    backend = load_backend(db['ENGINE'])
  File "/usr/local/lib/python3.7/dist-packages/django/db/utils.py", line 110, in load_backend
    return import_module('%s.base' % backend_name)
  File "/usr/lib/python3.7/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "/usr/local/lib/python3.7/dist-packages/sql_server/pyodbc/base.py", line 7
    except ImportError, e:
                      ^
SyntaxError: invalid syntax

I am not sure how to proceed from here. I am unable to understand where I am doing wrong. I want to build an image which is capable of connecting to MSSQL DB which exist on the server. I am running default docker machine on my local windows machine using docker toolbox. From my local system i connect to Database using windows authentication.

Answer 1

I believe you may have not installed the package django-mssql-backend.

pip install django-mssql-backend

This should help.

Answer 2

your Django version is too old

Django 1.5 supports Python 2.6.5 and later.

If you're under Linux and want to check the Python version you're using, run python -V from the command line.

If you want to check the Django version, open a Python console and type

import django django.VERSION (2, 0, 0, 'final', 0)

Answer 3

If you look close to your error, there is no indication that the application failed to connect with MSSQL or anything that is related to the DB connection.

  File "/usr/local/lib/python3.7/dist-packages/sql_server/pyodbc/base.py", line 7
    except ImportError, e:
                      ^
SyntaxError: invalid syntax

There is syntax Error in your code.

Also will suggest using alpine base Docker image or offical python image so will little effort to maintain dependency for your app.

You can look here and here.