Stop creating new toy assets when restarting the docker-compose stack

[Flix6x]

Current situation

1. User runs docker compose up using the docker-compose.yml: toy account, toy user and toy assets created. Assets:
   • NL transmission zone
   • toy-building
   • toy-battery
   • toy-solar
2. User reruns docker compose up: toy account and toy user already exist (not recreated), but some of the toy assets are recreated. Assets:
   • NL transmission zone
   • toy-building (x2)
   • toy-battery (x2)
   • toy-solar (x2)
3. Et cetera. Assets after N down -> up:
   • NL transmission zone
   • toy-building (x N)
   • toy-battery (x N)
   • toy-solar (x N)

Ideas

1. Adjust cli.data_add.add_toy_account to prevent new toy assets being created if they exist already.
2. Adjust docker-compose.yml to not rerun flexmeasures add toy-account --name 'Docker Toy Account' when that account already exists.

   if ! flexmeasures list accounts | grep -q "Docker Toy Account"; then
       flexmeasures add toy-account --name 'Docker Toy Account'
   fi
   

3. Adjust docker-compose.yml to not rerun flexmeasures add toy-account --name 'Docker Toy Account' after the first time docker compose up ran.

   if [ ! -f /app/instance/.toy_account_created ]; then
       flexmeasures add toy-account --name 'Docker Toy Account'
       touch /app/instance/.toy_account_created
   fi
   

Considerations

From a user perspective, I like the third option best. Why? Because I imagine that as a first-time user it's nice that you get a toy site to play around with, but once you set up your own site you will probably delete the toy site/account and it would feel really weird when it reappears the next time you run docker compose up. Even better might be to do the opposite, by having the marker file (named .create-toy-account) in the repo, and removing it the first time docker compose up runs. That way it's slightly nicer in the sense that a) the marker file does not need to live indefinitely on the user's device, and b) having the file explicitly in our repo better signals this design pattern, where temporary marker files are used for first-time use, and this can even be clearly documented inside the file itself.

[nhoening]

Pretty good analysis.

• Maybe more explicit name: .create-toy-account-on-first-run.
• Would it apply only to running per docker compose or in general?
• We can also consider adding a line to the output which says "Not creating toy account (already happened once). You can run flexmeasures add toy-account any time."

[Flix6x]

Good suggestions. I had in mind only the docker compose usage for this feature.

[nhoening]

It could be for using Docker in general

[Flix6x]

I don't understand, please elaborate. The instructions that add the toy account are in the docker-compose.yml, which is why that is my point of focus.

[nhoening]

I don't understand, please elaborate. The instructions that add the toy account are in the docker-compose.yml, which is why that is my point of focus.

Ah you are correct, so let's limit it to docker compose, indeed.

So I would rename the state file and add something to the output, as suggested.

[Flix6x]

I guess a logical place for the marker/state file to live would be in the flexmeasures-instance folder. The repo itself does not have that yet. Is that where we should put it? Or instance? Or otherwise?

[nhoening]

Flask has a definition of an instance directory, in the code we find it via Flask("flexmeasures").instance_path (found it in config_utils.py).

Maybe this helps?

import os
from flask import Flask

os.path.join(
    Flask("flexmeasures").instance_path, ".create-toy-account-on-first-run"
)

[Flix6x]

I guess it should be the directory on the host machine that ends up being mapped to that Flask instance folder inside the container. So that would be the flexmeasures-instance folder on the host container, according to our own docker-compose.yml.