Ecto Sandbox, Projections and In Memory adapter about commanded HOT 3 OPEN

If you have your Repo setup using Sandbox mode in tests, which work by starting a transaction at the beginning of a test and the rolling it back at the end, then the test's connection and the projector's connection cannot see each other's un-commited writes.

You would either need to allow the projector process access to the test's sandbox (https://hexdocs.pm/ecto_sql/Ecto.Adapters.SQL.Sandbox.html), or stop using the sandbox altogether and truncate tables as in the wiki.

from commanded.

Hey @drteeth (cool name btw), your explanation makes sense, and thanks for it.

We tried the allow configuration as per Ecto's documentation, and we are uncertain as to proceed.

We tried that, but we were still getting no projections from the projector after we run the command (with strong consistency).

What we did was, in the test file, set the mode to shared, with the current process as pid and the pid of the projector as allow. We found the projectors pid via which_children on its supervisor.

Maybe we should start the projector manually at the beginning of the test? Do you have more ideas we can try?

from commanded.

Yes starting the projector at the start of your test makes sense. use:

pid = start_supervised!(YourProjector)

so that it is properly cleaned up by the test

from commanded.