This commit includes functionality to turn on
the object serializer for network communication.
This is done the following way:
- On incoming connections, a process will detect
whether the client supports the object serializer
and will only serialize responses with it, if it does
- On outgoing connections, the command line flag is used
to determine whether the object serializer should be used
to send data.
This way, a cluster can run in mixed mode. To upgrade one
can upgrade one process at a time and set the flag one process
at a time.
This is how this is tested on the simulator:
- The command line flag can take three options: on, off,
and random.
- For off, the object serializer will never we used.
- For on, the object serializer will be always used.
- For random, the simulator will flip a coin for each
process it starts up.
When the coordinator changes, we use delayedAsyncVar() to reduce
the frequency for cluster controller to send the updated connectedCoordinatorsNumDelayed
to clients.
This help reduce the cluster controllers workload
Change the rst document file;
Change the coding style to be consistent with the nearby code;
Ensure we always initilize the connectedCoordinatesNum to 0
even when the variable is not used.
A client will always try to connect all coordinators.
This commit let Status track the number of connected coordinators
for each client.
This allows us to do canary in coordinators. For example,
when we switch from non-TLS to TLS, we can switch 1 coordinator
from non-TLS to TLS. This can help check if a client has the ability
to connect through TLS.
We can make the non-TLS to TLS switch for each coordinators
one by one. This avoid the risk of losing connection in the switch.
- NetworkAddress now contains IPAddress object which can be either
IPv4 or IPv6 address. 128bits are used even for IPv4 addresses,
however only 32bits are used when using/serializing IPv4 address.
- ConnectPacket is updated to store IPv6 address. Backward compatible
with old format since the first 32bits of IP address field is used
for serialization of IPv4.
- Mainly updates rest of the code to use IPAddress structure instead
of plain uint32_t.
- IPv6 address/pair ports should be represented as `[ip]:port` as per
convention. This applies to both cluster files and command line
arguments.