auto-loading settings

[edublancas]

we have a bunch of configuration settings that users can tweak. However, to change them, users have to put them in all their notebooks.

A better alternative would be to let them define the config project-wide in a pyproject.toml file (which is becoming standard in the Python ecosystem).

Example, a sample pyproject.toml could look like this:

[tool.jupysql.SqlMagic]
feedback = true
autopandas = true

Note that we should recursively look for the pyproject.toml, you can copy this function.

This behavior should be triggered when loading the extension. e.g., running %load_ext sql should display a message if a pyproject.toml is found and it should print the loaded settings and its values.

Some edge cases:

• if the option doesn't exist, we should display a message when loading the settings
• if there's a typo, we should provide a did you mean {x}? hint in the message (e.g., fedback instead of feedback)
• if assigning the value throws an error, we should show a message and tell the user, the default value will be used

e.g., the user has autopandas="not-a-valid-value"

[bbeat2782]

Acceptance Criteria

1. Running %load_ext sql triggers pyproject.toml file and displays a message that it found the file, prints out loaded settings, and changes configuration settings
2. If pyproject.toml does not exist, it displays a message
3. If there's a typo on one of the settings, it displays a message hinting at what a user might intend
4. If an invalid value for setting is provided, it displays a message that it is not a valid value and uses the default value instead.
5. Add documentation for explaining setting up pyproject.toml
6. Add test functions

[edublancas]

A few observations:

Running %load_ext sql triggers pyproject.toml file and displays a message that it found the file, prints out loaded settings, and changes configuration settings

This should trigger loading the file and notify the user if it found it. it should also look up in parent directories (in case the notebook is in project/notebooks/mynotebook.ipynb but the config file is in project/pyproject.toml)

If pyproject.toml does not exist, it displays a message

No need to do anything if the file doesn't exist

If there's a typo on one of the settings, it displays a message hinting at what a user might intend
If an invalid value for setting is provided, it displays a message that it is not a valid value and uses the default value instead.

these two are highly related. you can use difflib if there's something in the config file (under the tool.jupysql.SqlMagic section) that doesn't exist, you check if there are close matches. if so, the error message should suggest the fixed version. if there are no close matches, you simply return the value in the config file and tell the user that those are invalid, and show a link to the docs