Fix handling of invalid and empty filter queries

[paescuj]

Scope

• Filters can consist of empty rules ({}), which is valid according to the Filter type as well as the parseFilter() function
  • This case is now covered in applyQuery() by checking for undefined operators
• If a filter query is invalid (either invalid JSON or invalid rules), the request should fail early with InvalidQueryError
  • Until now, invalid filter queries where passed along even if sanitization failed

Potential Risks / Drawbacks

• As an alternative to throwing an error, we could also ignore invalid values (clear the filter value) and proceed with the request. That doesn't make much sense to me, though, as the client would assume a successful response to be filtered.

Review Notes / Questions

• Sanitization fix applies to deep filter as well as this reuses the sanitization function recursively.
• Examples for testing:
  • Invalid

    filter=null
    filter={"name": null}
    filter={"name":}
    ...
    

  • Valid

    filter=
    filter={}
    filter={"name": {}}
    filter={"name": []}
    ...
    

---

Fixes #22042

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🦋 Changeset detected

Latest commit: 745c735

The changes in this PR will be included in the next version bump.

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Name	Type
@directus/api	Patch
directus	Patch

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[hanneskuettner]

According to our types filter={"name": []} should not be a valid filter, as far as I understand them.

export type Filter = LogicalFilter | FieldFilter;

export type FieldFilter = {
	[field: string]: FieldFilterOperator | FieldValidationOperator | FieldFilter;
};

and neither FieldFilterOperator nor FieldValidationOperator are valid empty arrays.

[paescuj]

According to our types filter={"name": []} should not be a valid filter, as far as I understand them.

export type Filter = LogicalFilter | FieldFilter;

export type FieldFilter = {
	[field: string]: FieldFilterOperator | FieldValidationOperator | FieldFilter;
};

and neither FieldFilterOperator nor FieldValidationOperator are valid empty arrays.

Maybe 👀 This is out of scope for this PR, though, as it touches another part of the app and we would first have to decide

• whether we indeed want to treat it as invalid input - the current behavior, which is to translate it into {} kinda makes sense to me...
• what should happen (throw error, other fallback value, ...)