The server tells the client the hash of each tile it sends (calculated
from the contents of the tile, not its PNG encoding). When the client
asks for a tile to be refreshed, it tells the server what the hash of
the existing tile is. If the server notices that the tile contents
hasn't actually changed, it doesn't PNG encode it and doesn't send it
to the client.
The intent is that this will reduce load on the server and also avoid
unnecessary tile traffic.
Change-Id: Ia06ca68655ea984ed4319f24f4470afda322eccf
Use a new protocol message, 'resetidle' to inform Admin clients
whenever a user has done anything in a document view. This is a
message that Admin clients need to subscribe to.
Also add the current idle time for each document to the 'documents'
message.
To reduce protocol chatter, the idle time is updated at most once per
10 s.
Change-Id: I418e82b05048a3628f21dcd240ccd974b3a01356
Reviewed-on: https://gerrit.libreoffice.org/31653
Reviewed-by: Tor Lillqvist <tml@collabora.com>
Tested-by: Tor Lillqvist <tml@collabora.com>
