Waveform generator generates data for the same period over and over

[jeremyestein]

[...] There [was] old data in the fakeuds schema. I was able to clear this out using an SQL script, but it would be good to document this somewhere, and I'm not sure what the best way to do it is. Alternatively, could we pass an option to clear the fakeuds schema on startup?

Originally posted by @thompson318 in #145 (review)

[linear]

EMA-92

[jeremyestein]

I would be a bit nervous about introducing a feature that explicitly wipes the database. But you could manipulate the docker volume commands (eg emap docker down --volumes) to delete the fakeuds volume. In production it's an external database, not in a docker volume.

Another option would be for the generator to store its time progress in eg. emap-star, and then when it restarts it uses that time to restart from, to avoid overlapping data.

[thompson318]

Thanks @jeremyestein, emap docker down --volumes seems to solve the problem.
I think adding a note to the waveform-controller readme advising to use emap docker down --volumes if you see duplicate patients in the controller log would be the simplest way to fix this.