Query string support (Annex I) with client validation (check the correct formation of URLs)

[tobbee]

See the Issue for dash.js for the other side: Dash-Industry-Forum/dash.js#4440

A possible implementation could be that a config parameter triggers signalling of query strings, and that content is only delivered if the query parameters are added to the content requests.

We need to add the URLParameters part to dash-mpd library to support this feature.

As a next step, we can introduce a new url parameter

/annexI_a=1,b=2

That should match query strings in the manifest request:

?a=1&b=2

for a total URL like

livesim2/annexI_a=1,b=2/testpic_2s/Manifest.mpd?a=1&b=2

which should result in an extra Annex I element being inserted, and
that each later segment request is checked for the presence of these
query string parameters.

One could possibly have a few different variants for

• only video
• video and audio

by using different /annexI_ options.

Another alternative would be to redirect and include the query string in the redirect location.

[tobbee]

The first idea is to use CATS.
The client should use the same ID as used for CMCD.