In supervised nodes, the Supervisor's NodeConfig$scripts vector adds scripts to
the end of the user-provided scripts (options.scripts_to_load), so they load
_after_ any user-provided ones. This can cause confusing redef pitfalls when
users expect their customizations to run last, as they normally do.
This adds two members in Supervisor::NodeConfig, `addl_base_scripts` and
`addl_user_scripts`, to store scripts to load before and after the user scripts,
respectively. The latter serves the same purpose as the old `scripts` member,
which is still there but deprecated (in scriptland only). It functions as
before, after any scripts added via `addl_user_scripts`.
The Supervisor generates this event every time it receives a status update from
the stem, meaning a node got created or re-created. A corresponding
SupervisorControl::node_status event relays the same information for users
interacting with the Supervisor over Broker.
When omitted, the node inherits the Supervisor's bare-mode
status. When true/false, the new Zeek node will enable/disable bare
mode, respectively. It continues to load any scripts passed at the
command line and in the additional scripts list already provided in
the node configuration.
Includes testcase.
The NodeConfig record now has a table for specifying environment variable names
and values, which the supervisor sets in the created node.
This also repositions the cpu_affinity member to keep the order the same in
the corresponding script-layer and in-core types.
Includes testcase.
Also have stem process execv() with original command-line arguments so
that they're re-parsed and inherited correctly by supervised-nodes in
the event the stem process needs to be re-created.
More aspects of the cluster configuration to get fleshed out later,
but a basic cluster like one would use for a live deployment
can now be instantiated and run under supervision. The new
clusterized-pcap-processing supervisor mode is also not done yet.
The process hierarchy and all supervisor control commands are now
working (e.g. status, create, destroy, restart), but nodes are
not currently spawned with the desired configuration parameters so
they don't yet operate as real cluster nodes (e.g. worker, logger,
manager, proxy).
