use weakmap to avoid references from node to datadog stores #4953
+58
−9
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What does this PR do?
Use WeakMap to avoid references from Node to Datadog stores.
Motivation
When using AsyncLocalStorage, it attaches the store to the underlying resource directly. This means that if the resource is cloned, everything in all stores referenced by that resource will also be cloned, and some objects that may be referenced like sockets cannot be cloned, resulting in an error at best, and a segmentation fault at worst. Using a WeakMap makes it so that it's the map that references both a handle that is used as the store, and the real store stored in the map so that the store is no longer cloned.
This is an issue with
AsyncLocalStorage
and not with dd-trace so it should be fixed in Node, but for now we need to at least fix the immediate issue in the library.