lawnchair | caching expensive code in Redis or in the Ruby process | Caching library

I am getting the following error:

java.lang.IllegalArgumentException: No available camera can be found.

when calling and instance method ProcessCameraProvider.bindToLifecycle(). See this in the context of the code below by searching for "------ Code Crashes Here --------------".

How do I prevent this error and subsequent crashing of the app? More specifically, how do I ensure the CameraSelector can return a camera instance for the Nexus 6?

It appears there is something wrong with the CameraSelector used in this call. If I set a breakpoint on the bindToLifecycle line, and debug up to that point and add a watch for `cameraProvider.hasCamera(cameraSelector) it returns false. Maybe this is not intended to return true until the bindToLifecycle method has been called. If so, how can I verify the cameraSelector object has been created sucessfully (successfully meaning it points to an actual camera object)?

In the creation of the cameraSelector object, I use the requireLensFacing method in the builder, so it appears the Nexus 6 hardware does not tag anything with these LENS_FACING_BACK or LENS_FACING_FRONT and therefore does not return any camera instance? Do I understand this correctly?

I should note that this error did not occur when the exact same code was run on a Nexus 5, which is why I am inclined to think it is a hardware issue.

I also tried the LENS_FACING_FRONT int, but had the same error. If I remove the requireLensFacing build component altogether I get a different error:

java.util.NoSuchElementException