How to pair a device using qr-code and commission wifi/thread

[caipiblack]

Problem

I'm looking for the correct way to pair a device with qr-code and commission the device using the Matter stack.

Before this PR (#12909) the chip-tool example was doing the commissioning step when the callback OnPairingComplete() was triggered.

Why this example has been removed ? It's not the good way ?

Also, I found some discussions here: #14429

As I understand there are two way's to do this:

1. Decode the QR Code to get RendezvousParameters and use this function:

CHIP_ERROR DeviceCommissioner::PairDevice(NodeId remoteDeviceId, RendezvousParameters & rendezvousParams,
                                          CommissioningParameters & commissioningParams)

Like this the commissioning is performed automaticaly but we have to get the informations from the QR Code and we need to know (before the commissioning) the thread/wifi credentials

2. Pass the QR Code to this function, and use Network Commissioning Cluster to commission the device (not sure if possible)

CHIP_ERROR PairDevice(NodeId remoteDeviceId, const char * setUpCode);

Like this we just have to supply the QR Code, when the callback OnPairingComplete() is triggered we can ask the user for wifi/thread credentials

I'm really not sure to know what is the best way to do it.

What are these functions really intended for ??

Which function is future proof ?

Why the function with const char * setUpCode parameter doesn't have CommissioningParameters ?

[cecille]

Please see #14429. This got a little stale as we prioritized some other work in the lead up to the last branch, but I should get back to it either late today or early next week.

[caipiblack]

@cecille : I also have more questions:

What is the final objective of all the commissioning callbacks ?

• Is it just to get informations about the commissioning status ? Or is there something to do in the callbacks during the commissioning ?

Also, is there any plans to improve these callbacks ? (regroup them and add more status)

Currently If I do the commissioning of a thread device from the application, we have to see the Matter logs to know what happens,

I think it should be good to implement more states in the OnStatusUpdate() callback so we can use it to display "commissioning status" on the final application.

For example:

• Searching the device (BLE, SoftAP, OnNetwork)
• Device discovered (BLE, SoftAP, OnNetwork)
• Waiting for the device in the end network (should be called when we know the device is going to connect on final network)
• Device discovered in the end network

Or better: add a status for each commissioning steps in chip::Controller::DevicePairingDelegate::Status !

    enum Status : uint8_t
    {
        SecurePairingSuccess = 0,
        SecurePairingFailed,
    };

    /////////// callbacks from DevicePairingDelegate /////////
    void OnStatusUpdate(chip::Controller::DevicePairingDelegate::Status status) override;
    void OnPairingComplete(CHIP_ERROR error) override;
    void OnCommissioningComplete(NodeId deviceId, CHIP_ERROR error) override;

[cecille]

Callbacks cleanup issue: #15612

Please feel free to add status callback updates if you will find them helpful. You can also achieve this by using a custom commissioner delegate.

[cecille]

#14429 handles this issue. Callbacks is tracked in another issue, so closing this.