django - Command 01_migrate failed on Amazon Linux 2 AMI

Question

I have a Django project which is deployed to Elastic Beanstalk Amazon Linux 2 AMI. I installed PyMySQL for connecting to the db and i added these lines to settings.py such as below;

import pymysql

pymysql.version_info = (1, 4, 6, "final", 0)
pymysql.install_as_MySQLdb()

And also i have a .config file for migrating the db;

container_commands:
  01_migrate:
    command: "django-admin.py migrate"
    leader_only: true
option_settings:
  aws:elasticbeanstalk:application:environment:
    DJANGO_SETTINGS_MODULE: mysite.settings

Normally, i was using mysqlclient on my Linux AMI with this .config file but it doesn't work on Linux 2 AMI so i installed the PyMySQL. Now, i'm trying to deploy the updated version of my project but i'm getting an error such as below;

Traceback (most recent call last):
  File "/opt/aws/bin/cfn-init", line 171, in <module>
    worklog.build(metadata, configSets)
  File "/usr/lib/python2.7/site-packages/cfnbootstrap/construction.py", line 129, in build
    Contractor(metadata).build(configSets, self)
  File "/usr/lib/python2.7/site-packages/cfnbootstrap/construction.py", line 530, in build
    self.run_config(config, worklog)
  File "/usr/lib/python2.7/site-packages/cfnbootstrap/construction.py", line 542, in run_config
    CloudFormationCarpenter(config, self._auth_config).build(worklog)
  File "/usr/lib/python2.7/site-packages/cfnbootstrap/construction.py", line 260, in build
    changes['commands'] = CommandTool().apply(self._config.commands)
  File "/usr/lib/python2.7/site-packages/cfnbootstrap/command_tool.py", line 117, in apply
    raise ToolError(u"Command %s failed" % name)
ToolError: Command 01_migrate failed

How can i fix this issue?

Answer 1

Amazon Linux 2 has a fundamentally different setup than AL1, and the current documentation as of Jul 24, 2020 is out of date. django-admin of the installed environment by beanstalk does not appear to be on the path, so you can source the environment to activate and make sure it is.

I left my answer here as well which goes into much more detail in how I arrived at this answer, but the solution (which I don't love) is:

container_commands:
    01_migrate:
        command: "source /var/app/venv/*/bin/activate && python3 manage.py migrate"
        leader_only: true

Even though I don't love it, I have verified with AWS Support that this is in fact the recommended way to do this. You must source the python environment, as with AL2 they use virtual environments in an effort to stay more consistent.