Annotation ref should not have items.

[glenrobson]

When doing this:

annotationPageRef = AnnotationPageRefExtended(id="http://example.com/annos.json", type="AnnotationPage")
print (annotationPageRef.jsonld())

you get:

{"@context": "http://iiif.io/api/presentation/3/context.json", "id": "http://example.com/annos.json", "type": "AnnotationPage"}

which is correct but after you add it to a canvas:

annotationPageRef = AnnotationPageRefExtended(id="http://example.com/annos.json", type="AnnotationPage")
        print (annotationPageRef.jsonld())
        canvas.annotations = [annotationPageRef]

        print (canvas.annotations[0].jsonld())

You get:

{"@context": "http://iiif.io/api/presentation/3/context.json", "id": "http://example.com/annos.json", "type": "AnnotationPage", "items": []}

Expected behaviour:

You shouldn't get an empty items array if its a reference.

Potential bug location(s):

Is it an auto items issue or is the AnnotationPageRefExtended being converted to a AnnotationPage?

[glenrobson]

It looks like its being converted:

annotationPageRef = AnnotationPageRefExtended(id="http://example.com/annos.json", type="AnnotationPage")
        print (f"AnnotationPageType: {type(annotationPageRef).__name__}")
        canvas.annotations = [annotationPageRef]
        print (f"canvas.annotations: {type(canvas.annotations[0]).__name__}")

results in:

AnnotationPageType: AnnotationPageRefExtended
canvas.annotations: AnnotationPage

[glenrobson]

This is a tempoary fix:

canvas.annotations = [AnnotationPageRef(__root__=annotationPageRef)]

which could be wrapped in a helper