Device Discovery should use EndpointReference for uniqueness

[ajcasagrande]

Observation
We have discovered that our Tapo C200 cameras all return the same serial number when queried via GetDeviceInformation.
We have also learned that the happytime-multi-onvif-server sets all camera serial numbers to 123456 by default.

Problem
Only 1 device of each type Tapo C200 and happytime can be added to EdgeX due to name conflicts.

Proposed Solution

Use the Endpoint Reference as specified in the ONVIF spec. This is available during WS-Discovery:

7.3.1 Endpoint reference
A device or an endpoint that takes the client role should use a URN:UUID [RFC4122] as the address property
of its endpoint reference.

The device or an endpoint that takes the client role shall use a stable, globally unique identifier that is constant
across network interfaces as part of its endpoint reference property. The combination of an wsadis:Address
and wsadis:ReferenceProperties provide a stable and globally-unique identifier.

Source

We have indeed confirmed that even when the device IP address changes, the EndpointReference stays the same, and is unique to all of our cameras.

[weichou1229]

@ajcasagrande
The modification can be done with the following steps:

1. Parse the EndpointReference from the probe response. https://github.com/IOTechSystems/onvif/blob/master/ws-discovery/networking.go#L43-L56
2. Replace the serial number with EndpointReference when discovering the device. https://github.com/edgexfoundry-holding/device-onvif-camera/blob/main/internal/driver/driver.go#L328

[cloudxxx8]

@ajcasagrande do you agree with Bruce's solution?

[weichou1229]

@ajcasagrande

I can get the EndpointReference from probe message as below two cameras:

TAPO C200

<wsdd:ProbeMatch>
  <wsa:EndpointReference>
    <wsa:Address>uuid:3fa1fe68-b915-4053-a3e1-c006c3afec0e</wsa:Address>
     <wsa:ReferenceProperties></wsa:ReferenceProperties><wsa:PortType>ttl</wsa:PortType>
  </wsa:EndpointReference>
  <wsdd:XAddrs>http://192.168.12.128:2020/onvif/device_service</wsdd:XAddrs>
  ...
</wsdd:ProbeMatch>

HIKVISION

<d:ProbeMatch>
 <wsadis:EndpointReference>
    <wsadis:Address>urn:uuid:cea94000-fb96-11b3-8260-686dbc5cb15d</wsadis:Address>
 </wsadis:EndpointReference>
 <d:XAddrs>http://192.168.12.123/onvif/device_service</d:XAddrs>
 ...
</d:ProbeMatch>

So we need to extract the uuid value 3fa1fe68-b915-4053-a3e1-c006c3afec0e and cea94000-fb96-11b3-8260-686dbc5cb15d to replace the serial number. Is that correct?

The PRs opened, could you help verify that?
#7
IOTechSystems/onvif#8