File parameter name in onUpload callback

[Laxilef]

Hi,

Is there any way to get the file parameter name before it finishes uploading? This is important because depending on the parameter name, we interact with the file differently.

Example of a multipart request:

POST /upload HTTP/1.1
Content-Type: multipart/form-data; boundary=----boundary

------boundary
Content-Disposition: form-data; name="fw"; filename="firmware.bin"
Content-Type: application/octet-stream

[binary data]
------boundary
Content-Disposition: form-data; name="fs"; filename="filesystem.bin"
Content-Type: application/octet-stream

[binary data]
------boundary--j

The only thing I found is _itemName in AsyncWebServerRequest, but it is private.

[mathieucarbou]

@Laxilef : Hi,
the filename is passed when the upload starts.
Have a look at the examples in the project: there are so many!
https://github.com/ESP32Async/ESPAsyncWebServer/blob/main/examples/Upload/Upload.ino

[Laxilef]

I looked at the examples. I don't need the file name, but the parameter name.

For example, the parameter name for the firmware.bin file is fw, and for the filesystem.bin file is fs (see example of a multipart request)

[mathieucarbou]

Sorry! I misread. Yeah I am not sure for that. Request object is filled during request parsing and callbacks are called during parsing. Any chance you tried to look into request->param() to see if they are here (with boom true for body params) ?

[mathieucarbou]

On the code it is parses here:
https://github.com/ESP32Async/ESPAsyncWebServer/blob/main/src/WebRequest.cpp#L507

then put in the params list. So it should be available by looking at request param with body==true

[mathieucarbou]

Ok so I looked at the code and did some tryouts and indeed the param are only added once the upload is completed...

In the form: Param[1]: name=fw, value=firmware.bin, isFile=1, size=1066624

And then accessible only in the request handler after the upload is processed.

That's lame, because the lib knows about these params before starting the upload process.... It process them but only the filename is passed to the handler

[mathieucarbou]

yeah. I have worked on the fix during that time...

See PR: #329

It is tested.

I added also an example to show how to flash an ESP32 with both firmware + fs images at the same time.
That's a pretty good idea to stack the 2 updates in the same file upload and this is lame that the lib does not support that.

I will ask the team to review and merge.

[mathieucarbou]

@Laxilef could you please point to the branch to test ? Thanks!

lib_deps = https://github.com/ESP32Async/ESPAsyncWebServer#upload

[Laxilef]

This looks great, thanks! I'll test it today/tomorrow and give you feedback :)

[Laxilef]

Tested, works as expected 🎉

[mathieucarbou]

thanks!