Unit test support

[tekhedd]

Immutable databases and automated unit tests

I'm trying Immu with the java client and a key-value adapter. Starting up and running is easy and it works.

I am having an "interesting" time making simple automated unit tests, because you can't easily clean out the database and start over. I have simple tests like:

• parse record, verify that the expected data and only that data has been inserted.
• Insert record that will overwrite existing key, verify that history fetching code finds it

Obviously I can't delete all the keys manually because there's also no way to iterate keys, and there will be a history of the deletion. :)

I came up with several ideas. All require logging in as the primary admin user. (Note: There is no way to add a secondary user with super-admin support from the command line, so unit tests have to run as "immudb".)

1. Delete database and recreate. There will be a record of deletion, but that's OK I guess.

Nope. You can't delete the active, connected database. And, in the latest versions, you can't log in without connecting to an existing database. :o

2. Create a new database (random or incrementing name) for each test

Works, but I have to have a primary database, unused, for the initial login, and be careful not to delete that. I can switch to the primary database and then delete the random-named secondary database, if necessary.

Why is this needed

Automated unit tests want to run against an empty database to simplify validation.

If there were a way to log in but be initially unconnected to any database, that would probably solve most of the problem. :)

Additional context

I'm running in Java on linux against docker instances. It all works fine aside from the missing features.