Cannot pass additional arguments to rx.upload on_drop handler

[elliottsj]

Describe the bug
I want to pass an additional argument to the on_drop handler so that I can determine which field is uploaded into:

on_drop=State.handle_upload(rx.upload_files(upload_id=str(field)), field),

However, an error occurs:

TypeError: State.handle_upload() missing 1 required positional argument: 'field'

To Reproduce
Steps to reproduce the behavior:

• Code/Link to Repo:

class State(rx.State):
    fields: rx.Field[list[str]] = rx.field(["field1", "field2"])
    
    @rx.event
    async def handle_upload(self, files: list[rx.UploadFile], field: str) -> None:
        print("field", field)
        for file in files:
            print("file", file)

def index() -> rx.Component:
    return rx.foreach(
        State.fields,
        lambda field: rx.fragment(
            rx.text(field),
            rx.upload(
                rx.text(
                    "Drag and drop files here or click to select files"
                ),
                id=str(field),
                multiple=False,
                max_files=1,
                on_drop=State.handle_upload(rx.upload_files(upload_id=str(field)), field),
            )
        )
    )

Expected behavior
No error.

Screenshots

Specifics (please complete the following information):

• Python Version: 3.11.12
• Reflex Version: 0.7.11
• OS: macOS
• Browser (Optional):

Additional context
Related discussion: https://github.com/orgs/reflex-dev/discussions/5266

[linear]

ENG-5859 Cannot pass additional arguments to rx.upload on_drop handler

[Lendemor]

Seems like there are two separate issue with this snippet:

• The first is that the signature of on_drop does not specify any extra args, so extra args will not be passed through (the field you pass in the render function is simply ignored, and because your event handler expect it as args, it's throwing the error.

• The second is that with the current code, inside a rx.foreach, all the field will have the same id because of str(field) will compile to the name "field" rather than the value of that variable.