This PR introduces 4 new virtual tables aimed at replacing nodetool commands, working towards the long-term goal of replacing nodetool completely at least for cluster information retrieval purposes.
As you may have noticed, most of these replacement are not exact matches. This is on purpose. I feel that the nodetool commands are somewhat chaotic: they might have had a clear plan on what command prints what but after years of organic development they are a mess of fields that feel like don't belong. In addition to this, they are centered on C* terminology which often sounds strange or doesn't make any sense for scylla (off-heap memory, counter cache, etc.).
So in this PR I tried to do a few things:
* Drop all fields that don't make sense for scylla;
* Rename/reformat/rephrase fields that have a corresponding concept in scylla, so that it uses the scylla terminology;
* Group information in tables based on some common theme;
With these guidelines in mind lets look at the virtual tables introduced in this PR:
* `system.snapshots` - replacement for `nodetool listnapshots`;
* `system.protocol_servers`- replacement for `nodetool statusbinary` as well as `Thrift active` and `Native Transport active` from `nodetool info`;
* `system.runtime_info` - replacement for `nodetool info`, not an exact match: some fields were removed, some were refactored to make sense for scylla;
* `system.versions` - replacement for `nodetool version`, prints all versions, including build-id;
Closes#9517
* github.com:scylladb/scylla:
test/cql-pytest: add virtual_tables.py
test/cql-pytest: nodetool.py: add take_snapshot()
db/system_keyspace: add versions table
configure.py: move release.cc and build_id.cc to scylla_core
db/system_keyspace: add runtime_info table
db/system_keyspace: add protocol_servers table
service: storage_service: s/client_shutdown_hooks/protocol_servers/
service: storage_service: remove unused unregister_client_shutdown_hook
redis: redis_service: implement the protocol_server interface
alternator: controller: implement the protocol_server interface
transport: controller: implement the protocol_server interface
thrift: controller: implement the protocol_server interface
Add protocol_server interface
db/system_keyspace: add snapshots virtual table
db/virtual_table: remove _db member
db/system_keyspace: propagate distributed<> database and storage_service to register_virtual_tables()
docs/design-notes/system_keyspace.md: add listing of existing virtual tables
docs/guides: add virtual-tables.md
7a3930f7cf