fix(core): match nested event filters when an ancestor key is missing…

.changeset/nested-event-filter-exists-false.md

@@ -0,0 +1,7 @@
+---
+"@trigger.dev/core": patch
+---
+
+Fix `eventFilterMatches` so nested filters that assert the absence of a value match when an ancestor key is missing or `null`, instead of failing before the filter is evaluated. A missing payload is now matched like an empty object: it's how `$exists` behaves on nested paths elsewhere, and how these filters already behaved for a missing key at the top level.
+
+This changes the result only for filters whose leaves match a missing key today, i.e. `$exists: false`, `$isNull: false` and `$anythingBut`. Filters that require a value (`$exists: true`, `$startsWith`, `$gt`, value arrays, ...) are unchanged. It fixes `retry.fetch`'s `bodyFilter` (e.g. `{ error: { retryAfter: [{ $exists: false }] } }`) not matching responses that have no `error` object.

packages/core/src/eventFilterMatches.ts

@@ -5,16 +5,17 @@ import type { EventFilter } from "./schemas/eventFilter.js";
 // If the values of the array are objects, then we are doing content filtering
 // An example would be [{ $endsWith: ".png" }, { $startsWith: "images/" } ]
 export function eventFilterMatches(payload: any, filter: EventFilter): boolean {
-  if (payload === undefined || payload === null) {
-    if (Object.entries(filter).length === 0) {
-      return true;
-    } else {
-      return false;
-    }
-  }
+  // A missing (undefined/null) payload is matched like an empty object, so that a missing payload and
+  // a missing key are treated the same way. Filters that assert the absence of a value (`$exists:
+  // false`, `$isNull: false`, `$anythingBut`) therefore match when an ancestor key is missing or
+  // null, instead of failing before the filter is evaluated. This is the same result nested paths
+  // give in MongoDB-style filters, and the same result these filters already gave for a missing key
+  // at the top level. Filters that need a value (`$exists: true`, `$startsWith`, `$gt`, ...) still
+  // don't match `undefined`.
+  const payloadObject = payload === undefined || payload === null ? {} : payload;
 
   for (const [patternKey, patternValue] of Object.entries(filter)) {
-    const payloadValue = payload[patternKey];
+    const payloadValue = payloadObject[patternKey];
 
     if (Array.isArray(patternValue)) {
       if (patternValue.length === 0) {

packages/core/test/eventFilterMatches.test.ts

@@ -8,6 +8,12 @@ describe("eventFilterMatches", () => {
     expect(eventFilterMatches(payload, filter)).toBe(true);
   });
 
+  it("should return true if the payload is null and the filter is empty", () => {
+    const payload = null;
+    const filter: EventFilter = {};
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
   it("should return false if the payload is undefined and the filter isn't empty", () => {
     const payload = undefined;
     const filter: EventFilter = {
@@ -16,6 +22,22 @@ describe("eventFilterMatches", () => {
     expect(eventFilterMatches(payload, filter)).toBe(false);
   });
 
+  it("should return true if the payload is undefined and the filter asserts the absence of a key", () => {
+    const payload = undefined;
+    const filter: EventFilter = {
+      name: [{ $exists: false }],
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
+  it("should return true if the payload is null and the filter asserts the absence of a key", () => {
+    const payload = null;
+    const filter: EventFilter = {
+      name: [{ $exists: false }],
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
   it("should return true when payload matches string filter", () => {
     const payload = {
       name: "John",
@@ -209,6 +231,139 @@ describe("eventFilterMatches", () => {
     expect(eventFilterMatches(payload, filter)).toBe(true);
   });
 
+  it("should return true when payload does NOT have a nested key that $exists = false", () => {
+    const payload = {
+      name: "John",
+      age: 30,
+      isAdmin: false,
+      hobbies: ["reading", "swimming"],
+      address: {
+        street: "123 Main St",
+        city: "Anytown",
+      },
+    };
+    const filter: EventFilter = {
+      address: {
+        zip: [{ $exists: false }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
+  it("should return true when the parent key of a nested $exists = false filter is missing", () => {
+    const payload = {};
+    const filter: EventFilter = {
+      user: {
+        email: [{ $exists: false }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
+  it("should return true when the parent key of a nested $exists = false filter is null", () => {
+    const payload = {
+      user: null,
+    };
+    const filter: EventFilter = {
+      user: {
+        email: [{ $exists: false }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
+  it("should return true when the parent key of a nested $exists = false filter is an empty object", () => {
+    const payload = {
+      user: {},
+    };
+    const filter: EventFilter = {
+      user: {
+        email: [{ $exists: false }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
+  it("should return true when the payload is null and a nested $exists = false filter is used", () => {
+    const payload = null;
+    const filter: EventFilter = {
+      user: {
+        email: [{ $exists: false }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
+  it("should return true when the parent key of a nested $exists = false filter isn't an object", () => {
+    const payload = {
+      user: 42,
+    };
+    const filter: EventFilter = {
+      user: {
+        email: [{ $exists: false }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
+  it("should return true when a nested $isNull = false filter has no parent key", () => {
+    const payload = {
+      name: "John",
+    };
+    const filter: EventFilter = {
+      user: {
+        email: [{ $isNull: false }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
+  it("should return true when a nested $anythingBut filter has no parent key", () => {
+    const payload = {
+      name: "John",
+    };
+    const filter: EventFilter = {
+      user: {
+        email: [{ $anythingBut: "banned@example.com" }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
+  it("should return true when an ancestor key of a nested $exists = false filter is missing", () => {
+    const payload = {
+      account: {},
+    };
+    const filter: EventFilter = {
+      account: {
+        profile: {
+          settings: {
+            theme: [{ $exists: false }],
+          },
+        },
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
+  it("should return true when an array item does NOT have a nested key that $exists = false", () => {
+    const payload = {
+      items: [
+        { id: 1 },
+        {
+          id: 2,
+          deletedAt: "2024-01-01T00:00:00.000Z",
+        },
+      ],
+    };
+    const filter: EventFilter = {
+      items: {
+        deletedAt: [{ $exists: false }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(true);
+  });
+
   it("should return true when payload does match numeric condition", () => {
     const payload = {
       name: "John",
@@ -560,6 +715,167 @@ describe("eventFilterMatches", () => {
     expect(eventFilterMatches(payload, filter)).toBe(false);
   });
 
+  it("should return false when the parent key of a nested $exists = true filter is missing", () => {
+    const payload = {
+      name: "Jane",
+      age: 25,
+      isAdmin: true,
+    };
+    const filter: EventFilter = {
+      user: {
+        email: [{ $exists: true }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
+  it("should return false when the parent key of a nested $exists = true filter is null", () => {
+    const payload = {
+      name: "Jane",
+      age: 25,
+      isAdmin: true,
+      user: null,
+    };
+    const filter: EventFilter = {
+      user: {
+        email: [{ $exists: true }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
+  it("should return false when the parent key of a nested $exists = true filter isn't an object", () => {
+    const payload = {
+      name: "Jane",
+      age: 25,
+      isAdmin: true,
+      user: 42,
+    };
+    const filter: EventFilter = {
+      user: {
+        email: [{ $exists: true }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
+  it("should return false when a nested $isNull = true filter has no parent key", () => {
+    const payload = {
+      name: "Jane",
+    };
+    const filter: EventFilter = {
+      user: {
+        email: [{ $isNull: true }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
+  it("should return false when payload does have a nested key that $exists = false", () => {
+    const payload = {
+      name: "Jane",
+      age: 25,
+      isAdmin: true,
+      address: {
+        street: "456 Elm St",
+        city: "Othertown",
+      },
+    };
+    const filter: EventFilter = {
+      address: {
+        city: [{ $exists: false }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
+  it("should return false when the parent key of a nested value filter is missing", () => {
+    const payload = {
+      name: "Jane",
+      age: 25,
+      isAdmin: true,
+    };
+    const filter: EventFilter = {
+      user: {
+        email: ["john@example.com"],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
+  it("should return false when the parent key of a nested value filter is null", () => {
+    const payload = {
+      name: "Jane",
+      age: 25,
+      isAdmin: true,
+      user: null,
+    };
+    const filter: EventFilter = {
+      user: {
+        email: ["john@example.com"],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
+  it("should return false when the parent key of a nested $startsWith filter is missing", () => {
+    const payload = {
+      name: "Jane",
+      age: 25,
+      isAdmin: true,
+    };
+    const filter: EventFilter = {
+      user: {
+        email: [{ $startsWith: "john" }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
+  it("should return false when the parent key of a nested $gt filter is missing", () => {
+    const payload = {
+      name: "Jane",
+      age: 25,
+      isAdmin: true,
+    };
+    const filter: EventFilter = {
+      metrics: {
+        score: [{ $gt: 10 }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
+  it("should return false when a nested filter doesn't match even though a sibling key does", () => {
+    const payload = {
+      name: "Jane",
+      age: 25,
+      isAdmin: true,
+    };
+    const filter: EventFilter = {
+      name: ["Jane"],
+      user: {
+        email: [{ $exists: true }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
+  it("should return false when a nested filter doesn't match any item of an array", () => {
+    const payload = {
+      items: [
+        { id: 1, deletedAt: "2024-01-01T00:00:00.000Z" },
+        { id: 2, deletedAt: "2024-02-01T00:00:00.000Z" },
+      ],
+    };
+    const filter: EventFilter = {
+      items: {
+        deletedAt: [{ $exists: false }],
+      },
+    };
+    expect(eventFilterMatches(payload, filter)).toBe(false);
+  });
+
   it("should return false when the payload does not match the numeric filters", () => {
     const payload = {
       name: "Jane",