Hello
I try to create an aspnet webapi container to detect all available usb devices on my host device.
It works to connect a USB device from the container that was already connected when the container was started. But if i disconnect and reconnect the device is not longer available at the container.
Also my primary logic cannot reach the serial port after reconnect /dev/ttyACM0.
For my docker container i use the official dotnet image from microsoft and install libc6-dev and libusb
Dockerfile
FROM mcr.microsoft.com/dotnet/aspnet:6.0-focal
RUN apt-get update && apt-get install -y libc6-dev libusb-*
EXPOSE 5000/tcp
ENV ASPNETCORE_URLS "http://*:5000"
CMD dotnet /app/usbtest.dll
docker-compose.yml i think privileged and devices should be enough here
UDEV is according to my research, only relevant for Balena’s own containers.
usbtest:
privileged: true
tty: true
devices:
- '/dev:/dev'
image: registry.gitlab.company.com/test/test.balenausb:main-100020
labels:
io.balena.features.kernel-modules: true
network_mode: host
ports:
- '5000'
environment:
UDEV: 1
In my WebApi Project i use the LibUsbDotNet package. → LibUsbDotNet 3.0.97-alpha
My Controller in the WebApi looks like this
[Route("UsbDiscovery")]
[HttpGet]
public UsbDevice[] UsbDiscovery()
{
using (var context = new UsbContext())
{
var allDevices = context.List();
return allDevices.Select(o =>
{
try
{
if (!o.TryOpen())
{
return new UsbDevice
{
VendorId = o.VendorId,
ProductId = o.ProductId,
};
}
return new UsbDevice
{
MoreDataAvailable = true,
VendorId = o.VendorId,
ProductId = o.ProductId,
Manufacturer = o.Info.Manufacturer,
Product = o.Info.Product,
SerialNumber = o.Info.SerialNumber
};
}
finally
{
if (o.IsOpen)
{
o.Close();
}
o.Dispose();
}
}).ToArray();
}
}
The response look like this after reconnect
[
{
"moreDataAvailable": false,
"manufacturer": null,
"product": null,
"serialNumber": null,
"vendorId": 1027,
"productId": 24577
}
]
On first start with the connected device i have this
[
{
"moreDataAvailable": true,
"manufacturer": "FTDI",
"product": "USB Serial Converter",
"serialNumber": "ftE2S9L7",
"vendorId": 1027,
"productId": 24577
}
]
If i monitor my container with udevadm monitor i can see the reconnect events
root@66b43f8:/app# udevadm monitor
KERNEL[5492.312861] add /devices/pci0000:00/0000:00:14.0/usb1/1-5 (usb)
KERNEL[5492.322155] add /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.0 (usb)
KERNEL[5492.322300] add /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.0/tty/ttyACM0 (tty)
KERNEL[5492.322376] bind /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.0 (usb)
KERNEL[5492.322456] add /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.1 (usb)
KERNEL[5492.322523] bind /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.1 (usb)
KERNEL[5492.322572] bind /devices/pci0000:00/0000:00:14.0/usb1/1-5 (usb)
KERNEL[5510.786568] remove /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.0/tty/ttyACM0 (tty)
KERNEL[5510.786635] unbind /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.1 (usb)
KERNEL[5510.786898] unbind /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.0 (usb)
KERNEL[5510.789572] remove /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.0 (usb)
KERNEL[5510.789615] remove /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.1 (usb)
KERNEL[5510.789653] unbind /devices/pci0000:00/0000:00:14.0/usb1/1-5 (usb)
KERNEL[5510.789688] remove /devices/pci0000:00/0000:00:14.0/usb1/1-5 (usb)
UPDATE 2022-08-31
With switch to the alpine image i can now access the device after reconnect but the usbcontext still does not provide data about the manufacturer and the product.