Get current orientation angle for each page

Which product are you using?
PDF.js Express Viewer

PDF.js Express Version
8.7.4

Detailed description of issue
Is there any API we can call to get the current rotation angle of each page?

Expected behaviour
when I click on the page 2 I will get the current orientation angle of page 2

Hi there,

You can get current rotation angle of current page via

documentViewer.getCompleteRotation(1)
or 
documentViewer.getRotation()

Note that actual rotation operations are not available in pdf.js express:

Best regards,
Kevin Kim