Improve N+1 detection for simple hydration methods #45848
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We have N+1 detection for simple hydration methods that checks to see whether the hydration method made any DB queries at all. This makes sense, because a simple hydration method is called on each instance individually - if we make database calls *each time*, we're in trouble. Where this runs into issues is with cached data, where the simple hydration method is populating the cache - e.g. `:can_read` or `:can_write` dereferencing `api/*current-user-permissions-set*`. Currently we specifically exclude those hydration methods from the check. But after running into this again for a different simple hydration method, I think there's a more robust approach: - first, run the hydration method without counting DB queries - then, run it again and make sure we don't make any additional DB queries. There is a potential downside here: if someone wrote a simple hydration method with side effects, they'd potentially be very confused (in development - this doesn't run in prod!) when those side effects happened twice for a single hydration. But I *think* that's fairly unlikely.
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I forgot to commit this before. Tests seem to be failing due to [this](#45848)
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| [toucan2.tools.hydrate :as t2.hydrate])) | ||
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| (methodical/defmethod t2.hydrate/simple-hydrate | ||
| [:default ::some-silly-key-that-should-never-actually-be-hydrated!!!] |
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I forgot to commit this before. Tests seem to be failing due to [this](#45848)
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I forgot to commit this before. Tests seem to be failing due to [this](#45848)
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I forgot to commit this before. Tests seem to be failing due to [this](#45848)
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I forgot to commit this before. Tests seem to be failing due to [this](#45848)
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We have N+1 detection for simple hydration methods that checks to see whether the hydration method made any DB queries at all. This makes sense, because a simple hydration method is called on each instance individually - if we make database calls each time, we're in trouble.
Where this runs into issues is with cached data, where the simple hydration method is populating the cache - e.g.
:can_reador:can_writedereferencingapi/*current-user-permissions-set*. Currently we specifically exclude those hydration methods from the check.But after running into this again for a different simple hydration method, I think there's a more robust approach:
first, run the hydration method without counting DB queries
then, run it again and make sure we don't make any additional DB queries.
There is a potential downside here: if someone wrote a simple hydration method with side effects, they'd potentially be very confused (in development - this doesn't run in prod!) when those side effects happened twice for a single hydration. But I think that's fairly unlikely.