In commit 44a1daf we added the ability to read Scylla system tables with Alternator. This feature is useful, among other things, in tests that want to read Scylla's configuration through the system table system.config. But tests often want to modify system.config, e.g., to temporarily reduce some threshold to make tests shorter. Until now, this was not possible
This series add supports for writing to system tables through Alternator, and examples of tests using this capability (and utility functions to make it easy).
Because the ability to write to system tables may have non-obvious security consequences, it is turned off by default and needs to be enabled with a new configuration option "alternator_allow_system_table_write"
No backports are necessary - this feature is only intended for tests. We may later decide to backport if we want to backport new tests, but I think the probability we'll want to do this is low.
Fixes#12348Closesscylladb/scylladb#19147
* github.com:scylladb/scylladb:
test/alternator: utility functions for changing configuration
alternator: add optional support for writing to system table
test/alternator: reduce duplicated code