Importing book uses today's values for missing date parts

[texttheater]

Describe the bug
When importing a book from OpenLibrary, month and day are set to today's month and day.

To Reproduce
Steps to reproduce the behavior:

1. Find a book on OpenLibary, e.g., one published in 2022
2. Import it into a BookWyrm instance, e.g., on Feb 12, 2023

Expected behavior
The book is shown on BookWyrm as published in 2022 (month and date unspecified)

Actual behavior
The book is shown on BookWyrm as published on Feb 12, 2022

Additional context
Related issue: #743

[chdorner]

I just imported a book today from OpenLibrary which had its published date set correctly.

Do you have a specific book that I could check this with?

[texttheater]

Are you sure that's correct? On OpenLibrary it just says "2022". On the BookWyrm page you link to it says "13 Feb 2022". Looks like exactly the issue I'm describing.

[chdorner]

With the date and month yes, which is most likely related to #743. But the year is set correctly to 2022, not 2023.

[texttheater]

Sorry, my mistake. Fixed the description now.

[chdorner]

Did a bit of digging, and this is where it originally happens:

bookwyrm/bookwyrm/models/fields.py

Line 486 in 2c2daf5

date_value = dateutil.parser.parse(value)

value is set to "2022" coming from OpenLibrary's API and dateutil automatically turns this into datetime.datetime(2022, 2, 13, 0, 0).

In addition, and this is more related to #743, we would need to change how to store this data, it's currently using Django's models.DateTimeField which doesn't support missing day and month parts of a date.