What's the max byte-size that a web-socket request can be in order for DataMiner to be able to handle it?
The max data size that can be sent seems to be int32 max (2147483647 bytes or ~2047MiB).
Note that this is theoretical and unverified. There may be other limiting factors.
The receivebuffer in SLPort is 65535 bytes (0xFFFF or uint16 max) and can be filled 1024 times before flushing to SLProtocol.
So the total max data that can be received is 67107840 bytes (or ~63MiB) without flushing to SLProtocol.
There does not seem to be a hard limit to how many times can be flushed to SLProtocol.
Do note if a connector needs to receive messages larger than the ~63MiB it still can but will need to implement logic to reconstruct the message from the blocks of up to ~63MiB SLPort sends to SLProtocol
before DM10.1(CU18),DM10.2(CU6),DM10.2.8, the message could not be larger than 65535 bytes and could cause a SLPort crash, see RN33182 and RN34049.