# Dependency Management

The `requirements.txt` and `requirements_ansible.txt` files are generated from `requirements.in` and `requirements_ansible.in`, respectively, using `pip-tools` `pip-compile`.

## How To Use

Commands should from inside `./requirements` directory of the awx repository.

Make sure you have `patch, awk, python3, python2, python3-venv, python2-virtualenv, pip2, pip3` installed. The development container image should have all these.

### Upgrading or Adding Select Libraries

If you need to add or upgrade one targeted library, then modify `requirements.in`,
then run the script:

`./updater.sh`

#### Upgrading Unpinned Dependency

If you require a new version of a dependency that does not have a pinned version
for a fix or feature, pin a minimum version and run `./updater.sh`. For example,
replace the line `asgi-amqp` with `asgi-amqp>=1.1.4`, and consider leaving a
note.

Then next time that a general upgrade is performed, the minimum version specifiers
can be removed, because `*.txt` files are upgraded to latest.

### Upgrading Dependencies

You can upgrade (`pip-compile --upgrade`) the dependencies by running

`./updater.sh upgrade`.

## What The Script Does

This script will:

  - Update `requirements.txt` based on `requirements.in`
  - Update/generate `requirements_ansible.txt` based on `requirements_ansible.in`
    - including an automated patch that adds `python_version < "3"` for Python 2 backward compatibility
  - Removes the `docutils` dependency line from `requirements.txt` and `requirements_ansible.txt`


## Licenses and Source Files

If any library has a change to its license with the upgrade, then the license for that library
inside of `docs/licenses` needs to be updated.

For libraries that have source distribution requirements (LGPL as an example),
a tarball of the library is kept along with the license.
To download the PyPI tarball, you can run this command:

```
pip download <pypi library name> -d docs/licenses/ --no-binary :all: --no-deps
```

Make sure to delete the old tarball if it is an upgrade.

## UPGRADE BLOCKERs

Anything pinned in `*.in` files involves additional manual work in
order to upgrade. Some information related to that work is outlined here.

### django

For any upgrade of Django, it must be confirmed that
we don't regress on FIPS support before merging.

See internal integration test knowledge base article `how_to_test_FIPS`
for instructions.

If operating in a FIPS environment, `hashlib.md5()` will raise a `ValueError`,
but will support the `usedforsecurity` keyword on RHEL and Centos systems.

Keep an eye on https://code.djangoproject.com/ticket/28401

The override of `names_digest` could easily be broken in a future version.
Check that the import remains the same in the desired version.

https://github.com/django/django/blob/af5ec222ccd24e81f9fec6c34836a4e503e7ccf7/django/db/backends/base/schema.py#L7

### social-auth-app-django

django-social keeps a list of backends in memory that it gathers
based on the value of `settings.AUTHENTICATION_BACKENDS` *at import time*:
https://github.com/python-social-auth/social-app-django/blob/c1e2795b00b753d58a81fa6a0261d8dae1d9c73d/social_django/utils.py#L13

Our `settings.AUTHENTICATION_BACKENDS` can *change*
dynamically as Tower settings are changed (i.e., if somebody
configures Github OAuth2 integration), so we need to
_overwrite_ this in-memory value at the top of every request so
that we have the latest version
see: https://github.com/ansible/tower/issues/1979

### django-oauth-toolkit

Version 1.2.0 of this project has a bug that error when revoking tokens.
This is fixed in the master branch but is not yet released.

When upgrading past 1.2.0 in the future, the `0025` migration needs to be
edited, just like the old migration was edited in the project:
https://github.com/jazzband/django-oauth-toolkit/commit/96538876d0d7ea0319ba5286f9bde842a906e1c5
The field can simply have the validator method `validate_uris` removed.

### azure-keyvault

Upgrading to 4.0.0 causes error because imports changed.

```
  File "/var/lib/awx/venv/awx/lib64/python3.6/site-packages/awx/main/credential_plugins/azure_kv.py", line 4, in <module>
  from azure.keyvault import KeyVaultClient, KeyVaultAuthentication
ImportError: cannot import name 'KeyVaultClient'
```

### slackclient

Imports as used in `awx/main/notifications/slack_backend.py` changed
in version 2.0. This plugin code will need to change and be re-tested
as the upgrade takes place.

### django-jsonfield

Instead of calling a `loads()` operation, the returned value is casted into
a string in some cases, introduced in the change:

https://github.com/adamchainz/django-jsonfield/pull/14

This breaks a very large amount of AWX code that assumes these fields
are returned as dicts. Upgrading this library will require a refactor
to accomidate this change.

### pip and setuptools and wheel

The offline installer needs to have functionality confirmed before upgrading these.
Versions need to match the versions used in the pip bootstrapping step
in the top-level Makefile.

## Library Notes

### celery

This is only used for the beat feature (running periodic tasks).
This could be replaced, see: https://github.com/ansible/awx/pull/2530

### requests-futures

This can be removed when a solution for the external log queuing is ready.
https://github.com/ansible/awx/pull/5092

### asgi-amqp

This library is not compatible with channels 2 and is not expected
to become so. This drives other pins in the requirements file.