xds: fix a concurrency issue in CSDS ClientStatus responses #8795
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| Fixes #8642 |
dapengzhang0 reviewed Jan 5, 2022
sergiitk commented Jan 11, 2022
| XdsClient throwingXdsClient = new FakeXdsClient() { | ||
| @Override | ||
| Map<String, ResourceMetadata> getSubscribedResourcesMetadata(ResourceType type) { | ||
| Map<ResourceType, Map<String, ResourceMetadata>> getSubscribedResourcesMetadataSnapshot() { |
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Note: this was needed because I discovered this test to be false negative, see PR description:
Fix false negative in fetchClientConfig_unexpectedException,
where expected exception was actually caused by missing
bootstrap data, not by throwing error from the local
class implementation.
sergiitk commented Jan 11, 2022
Fixes an issue with ClientXdsClient.getSubscribedResourcesMetadata() executed out of shared synchronization context, and leading to: - each individual config dump containing outdated data when an xDS resource is updated during CsdsService preparing the response - config dumps for different services being out-of-sync with each other when any of the related xDS resources is updated during CsdsService preparing the response The fix replaces getSubscribedResourcesMetadata(ResourceType type) with atomic getSubscribedResourcesMetadataSnapshot() returning a snapshot of all resources for each type as they are at the moment of a CSDS request.
sergiitk force-pushed the csds-fix-concurrency branch from e0a40c7 to b3a3914 Compare | Ready for another review. |
dapengzhang0 approved these changes Jan 12, 2022
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Fixes an issue with ClientXdsClient.getSubscribedResourcesMetadata()
executed out of shared synchronization context, and leading to:
an xDS resource is updated during CsdsService preparing the response
other when any of the related xDS resources is updated during
CsdsService preparing the response
The fix replaces getSubscribedResourcesMetadata(ResourceType type)
with atomic getSubscribedResourcesMetadataSnapshot() returning
a snapshot of all resources for each type as they are
at the moment of a CSDS request.
Fix false negative in fetchClientConfig_unexpectedException,
where expected exception was actually caused by missing
bootstrap data, not by throwing error from the local
class implementation.