All current tests that use caches with custom data expiry values
now restore the default config when teardown. We need to prevent
new unsafe uses from being introduced.
Restoration code have also been added to a few other tests that modifies
static fields.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=228888041
This is safer and addresses a common source of confusion in the codebase because it's always explicit that the resource returned may not be present, whether because it's soft-deleted when projected to the given time or because it never existed in the first place.
In production code, the presence of the returned value is always checked. In test code, its presence is assumed using .get() where that is expected and convenient, as it not being present will throw an NPE that will cause the test to fail anyway.
Note that the roughly equivalent reloadResourceByForeignKey(), which is widely used in test code, is not having this same treatment applied to it. That is out of the scope of this CL, and has much smaller returns anyway because it's only used in tests (where the unexpected absence of a given resource would just cause the test to fail).
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=225424002
This should prevent having issues with hot key paths on entities that
experience a heavy WHOIS volume (e.g. contacts that registrars reuse on
many domains).
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=191506124
After investigating common domain create/update command usage
patterns by registrars, we noticed that it is frequent for a
given registrar to reuse both hosts (using a standardized set of
nameservers) as well as contacts (e.g. for privacy/proxy
services). With these usage patterns, potential per-registrar
throughput during high volume scenarios (i.e. first moments of
General Availability) suffers from hitting hot keys in Datastore.
The solution, implemented in this CL, is to add short-term
in-memory caching for contacts and hosts, analogous to how we are
already caching Registry and Registrar entities. These new
cached paths are only used inside domain flows to determine
existence and deleted/pending delete status of contacts and
hosts. This is a potential loss of transactional consistency, but
in practice it's hard to imagine this having negative effects, as
contacts or hosts that are in use cannot be deleted, and caching
would primarily affect widely used contacts and hosts.
Note that this caching can be turned on or off through a
configuration option, and by default would be off. We'd only want
it on when we really needed it, i.e. during a big launch.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187093378
