Upload
The Upload component can be used to upload files to the server.
You can pass components as children to customize its appearance. You can upload files by clicking on the component or by dragging and dropping files onto it.
rx.upload(
id="my_upload",
)
Selecting a file will add it to the browser's file list, which can be rendered
on the frontend using the rx.selected_files(id)
special Var. To clear the
selected files, you can use another special Var rx.clear_selected_files(id)
as
an event handler.
To upload the file(s), you need to bind an event handler and pass the special
rx.upload_files(upload_id=id)
event arg to it.
Multiple File Upload
Below is an example of how to allow multiple file uploads (in this case images).

class State(rx.State): """The app state.""" # The images to show. img: list[str] @rx.event async def handle_upload( self, files: list[rx.UploadFile] ): """Handle the upload of file(s). Args: files: The uploaded files. """ for file in files: upload_data = await file.read() outfile = rx.get_upload_dir() / file.filename # Save the file. with outfile.open("wb") as file_object: file_object.write(upload_data) # Update the img var. self.img.append(file.filename) color = "rgb(107,99,246)" def index(): """The main view.""" return rx.vstack( rx.upload( rx.vstack( rx.button( "Select File", color=color, bg="white", border=f"1px solid {color}", ), rx.text( "Drag and drop files here or click to select files" ), ), id="upload1", border=f"1px dotted {color}", padding="5em", ), rx.hstack( rx.foreach( rx.selected_files("upload1"), rx.text ) ), rx.button( "Upload", on_click=State.handle_upload( rx.upload_files(upload_id="upload1") ), ), rx.button( "Clear", on_click=rx.clear_selected_files("upload1"), ), rx.foreach( State.img, lambda img: rx.image( src=rx.get_upload_url(img) ), ), padding="5em", )
Uploading a Single File (Video)
Below is an example of how to allow only a single file upload and render (in this case a video).
class State(rx.State): """The app state.""" # The video to show. video: str @rx.event async def handle_upload( self, files: list[rx.UploadFile] ): """Handle the upload of file(s). Args: files: The uploaded files. """ current_file = files[0] upload_data = await current_file.read() outfile = ( rx.get_upload_dir() / current_file.filename ) # Save the file. with outfile.open("wb") as file_object: file_object.write(upload_data) # Update the video var. self.video = current_file.filename color = "rgb(107,99,246)" def index(): """The main view.""" return rx.vstack( rx.upload( rx.vstack( rx.button( "Select File", color=color, bg="white", border=f"1px solid {color}", ), rx.text( "Drag and drop files here or click to select files" ), ), id="upload1", max_files=1, border=f"1px dotted {color}", padding="5em", ), rx.text(rx.selected_files("upload1")), rx.button( "Upload", on_click=State.handle_upload( rx.upload_files(upload_id="upload1") ), ), rx.button( "Clear", on_click=rx.clear_selected_files("upload1"), ), rx.cond( State.video, rx.video(url=rx.get_upload_url(State.video)), ), padding="5em", )
Customizing the Upload
In the example below, the upload component accepts a maximum number of 5 files of specific types. It also disables the use of the space or enter key in uploading files.
To use a one-step upload, bind the event handler to the rx.upload
component's
on_drop
trigger.
class State(rx.State): """The app state.""" # The images to show. img: list[str] async def handle_upload( self, files: list[rx.UploadFile] ): """Handle the upload of file(s). Args: files: The uploaded files. """ for file in files: upload_data = await file.read() outfile = rx.get_upload_dir() / file.filename # Save the file. with outfile.open("wb") as file_object: file_object.write(upload_data) # Update the img var. self.img.append(file.filename) color = "rgb(107,99,246)" def index(): """The main view.""" return rx.vstack( rx.upload( rx.vstack( rx.button( "Select File", color=color, bg="white", border=f"1px solid {color}", ), rx.text( "Drag and drop files here or click to select files" ), ), id="upload2", multiple=True, accept={ "application/pdf": [".pdf"], "image/png": [".png"], "image/jpeg": [".jpg", ".jpeg"], "image/gif": [".gif"], "image/webp": [".webp"], "text/html": [".html", ".htm"], }, max_files=5, disabled=False, no_keyboard=True, on_drop=State.handle_upload( rx.upload_files(upload_id="upload2") ), border=f"1px dotted {color}", padding="5em", ), rx.grid( rx.foreach( State.img, lambda img: rx.vstack( rx.image(src=rx.get_upload_url(img)), rx.text(img), ), ), columns="2", spacing="1", ), padding="5em", )
Handling the Upload
Your event handler should be an async function that accepts a single argument,
files: list[UploadFile]
, which will contain FastAPI UploadFile instances.
You can read the files and save them anywhere as shown in the example.
In your UI, you can bind the event handler to a trigger, such as a button
on_click
event or upload on_drop
event, and pass in the files using
rx.upload_files()
.
Saving the File
By convention, Reflex provides the function rx.get_upload_dir()
to get the directory where uploaded files may be saved. The upload dir comes from the environment variable REFLEX_UPLOADED_FILES_DIR
, or ./uploaded_files
if not specified.
The backend of your app will mount this uploaded files directory on /_upload
without restriction. Any files uploaded via this mechanism will automatically be publicly accessible. To get the URL for a file inside the upload dir, use the rx.get_upload_url(filename)
function in a frontend component.
When using the Reflex hosting service, the uploaded files directory is not persistent and will be cleared on every deployment. For persistent storage of uploaded files, it is recommended to use an external service, such as S3.
Cancellation
The id
provided to the rx.upload
component can be passed to the special event handler rx.cancel_upload(id)
to stop uploading on demand. Cancellation can be triggered directly by a frontend event trigger, or it can be returned from a backend event handler.
Progress
The rx.upload_files
special event arg also accepts an on_upload_progress
event trigger which will be fired about every second during the upload operation to report the progress of the upload. This can be used to update a progress bar or other UI elements to show the user the progress of the upload.
class UploadExample(rx.State): uploading: bool = False progress: int = 0 total_bytes: int = 0 @rx.event async def handle_upload( self, files: list[rx.UploadFile] ): for file in files: self.total_bytes += len(await file.read()) @rx.event def handle_upload_progress(self, progress: dict): self.uploading = True self.progress = round(progress["progress"] * 100) if self.progress >= 100: self.uploading = False @rx.event def cancel_upload(self): self.uploading = False return rx.cancel_upload("upload3") def upload_form(): return rx.vstack( rx.upload( rx.text( "Drag and drop files here or click to select files" ), id="upload3", border="1px dotted rgb(107,99,246)", padding="5em", ), rx.vstack( rx.foreach( rx.selected_files("upload3"), rx.text ) ), rx.progress(value=UploadExample.progress, max=100), rx.cond( ~UploadExample.uploading, rx.button( "Upload", on_click=UploadExample.handle_upload( rx.upload_files( upload_id="upload3", on_upload_progress=UploadExample.handle_upload_progress, ), ), ), rx.button( "Cancel", on_click=UploadExample.cancel_upload, ), ), rx.text( "Total bytes uploaded: ", UploadExample.total_bytes, ), align="center", )
The progress
dictionary contains the following keys:
\{ 'loaded': 36044800, 'total': 54361908, 'progress': 0.6630525183185255, 'bytes': 20447232, 'rate': None, 'estimated': None, 'event': {'isTrusted': True}, 'upload': True }
API Reference
rx.upload
The styled Upload Component.
Prop | Type | Values | Default |
---|---|---|
accept | Union[dict, NoneType] |
|
disabled | bool |
|
max_files | int |
|
max_size | int |
|
min_size | int |
|
multiple | bool |
|
no_click | bool |
|
no_drag | bool |
|
no_keyboard | bool |
|
drag_active_style | Style | None |
Event Triggers
See the full list of default event triggersTrigger | Description |
---|---|
on_drop | Marked True when any Upload component is created. Fired when files are dropped. |