Internal Server Error with History

[Jojo144]

On my production server, history works well for new small projects. But for old projects I get "Internal Server Error" when I go on the history page.
I didn't succeed in reproducing the bug on a small example in a dev environment.

After some investigations, I realized that detailed_version.payer and detailed_version.owers returns None here:

ihatemoney/ihatemoney/history.py

Lines 96 to 101 in 710aee9

	details = {
	"date": detailed_version.date,
	"payer": describe_version(detailed_version.payer),
	"amount": detailed_version.amount,
	"owers": [describe_version(o) for o in detailed_version.owers],
	"external_link": detailed_version.external_link,

So if I replace describe_version(detailed_version.payer)) by str(Person.query.get(detailed_version.payer_id, project)) it works for the payer. I don't know how to do the same trick for owers.

• Any idea why the payer method returns None here?

• Any idea why the object detailed_version does not have owers attribute?

Is it linked to the fact that this relationship is manually defined?

ihatemoney/ihatemoney/models.py

Lines 644 to 649 in 710aee9

	billowers = db.Table(
	"billowers",
	db.Column("bill_id", db.Integer, db.ForeignKey("bill.id"), primary_key=True),
	db.Column("person_id", db.Integer, db.ForeignKey("person.id"), primary_key=True),
	sqlite_autoincrement=True,
	)

[Jojo144]

Is it link to this?
https://stackoverflow.com/questions/42457115/sqlalchemy-get-returns-none

I don't understand the answer really...

[zorun]

Thanks for the investigation. I don't understand the history code in details, sorry... Potentially, we manipulate old version of objects, and I don't know how it interacts with schema changes and migrations.

If I had to guess, I see two possibilities:

• either the history code does not handle migrations, so we need to take into account that old objects do not conform to the current database model (what a mess!)
• either your old projects did not correctly get migrations applied

I checked who wrote that code, and it's you 😄 #1223 But the complexity comes from previous code, of course.

[Jojo144]

I spent a couple of hours to investigate further but I didn't find anything convincing.
I propose #1359 as workaround.

[almet]

I'm closing this as we have a workaround for it now. Please reopen if you have another error.