OpenAPI Doc - how to show authorized values for an optional query parameter

[legalla]

Hi all,

Quick question about how to manage optional query paramters :
I would like the users to get capability to use or not an optional query parameter for a certain API.
So OK, that works as expected following FastAPI guide.
But my point now is :
For this optional parameter, I would like to get a set of authorized values.
If the parameter sent by the end user is not in the list, it raises an error.
So :

• Is there an easy way to show to end user within the Swagger UI which are the allowed values for this parameter, and a description for each of them ?
• In the meantime, I would like to show them as a list ("select" in HTML), to be sure that user can't make a mistake, and select an authorized value.

I've seen it with solutions using Swagger, so I assume this should be possible, but I didn't find a way to do in documentation (or maybe I missed it...)

Thanks a lot,

Environment

• OS: Linux - Ubuntu 18.04
• FastAPI Version [e.g. 0.3.0]:

0.63.0

• Python version:

Python 3.6.9

[Mause]

If the parameter you define is an enum, you will automatically get this functionality

[legalla]

Hi,

Thanks a lot, that works as expected.
I totally missed that part in the documentation.
One additional question :
Does Enum support "dynamic provisioning" ?
I mean, if I want to an Enum Model using values in a dB table, do we have a way to automatically populate the enum with the values within this table ?

Thanks again,

[Kilo59]

Does Enum support "dynamic provisioning" ?
I mean, if I want to an Enum Model using values in a dB table, do we have a way to automatically populate the enum with the values within this table ?

You can use the functional api to dynamically create an enum.

1. Look up your values from the database.
2. Create your enum using the functional enum API and that database values.

[tiangolo]

Thanks for the help here @Mause and @Kilo59 ! 👏 🙇

If the data you need to validate comes from a database you probably need to use dependencies for that: https://fastapi.tiangolo.com/tutorial/dependencies/

Sorry for the long delay! 🙈 I wanted to personally address each issue/PR and they piled up through time, but now I'm checking each one in order.

[github-actions]

Assuming the original need was handled, this will be automatically closed now. But feel free to add more comments or create new issues or PRs.