Kanta duplicates kanta_message records when context is null

[kubosuke]

Environment

• fly.io
• Elixir 1.17
• Postgres 14
• po files:

❯ find . -name "default.po"
./priv/gettext/nl/LC_MESSAGES/default.po
./priv/gettext/en/LC_MESSAGES/default.po

Overview

in our application, Kanta duplicates Message records and it causes unexpected behaviour.

as we investigate the behaviour, we found that unique constraint is defined at here:

kanta/lib/kanta/migrations/postgresql/v01.ex

Line 111 in 4df9af2

create_if_not_exists unique_index(@kanta_messages, [:context_id, :domain_id, :msgid])

but it didn't work properly, because we don't define any context, and contexts are registered as null in the database.
ref: https://stackoverflow.com/a/8289253

How about forcing users to define context, or set default context if it's not defined?

[ravensiris]

@kubosuke
Hi, got assigned to this issue.
Seems like you've made a PR but closed it.
Was there a reason for closing?
Did it not solve your issue?

[kubosuke]

@ravensiris
Hi thanks for your reply.

Yeah once I thought by applying default context we could resolve this issue like this:
https://github.com/curiosum-dev/kanta/pull/66/files

but finally we decided to apply additional UNIQUE constraint to :domain_id, :msgid cause it's easier and it doesn't require to modify current kanta codes. but it'd be nice if we can apply default context if it's missing.