fix(sync): synthesizer occurredAt 缺失时确定性回退 updatedAt→createdAt,墙钟仅最终兜底

原 occurredAt ?? new Date() 在 occurredAtField 缺失/不可解析时每次摄入产生新墙钟值 —
时间锚纳入 fact 变更检测后会被放大成伪 supersede 版本抖动。改为确定性回退链
(occurredAtField → updatedAt → createdAt),三者皆缺才落墙钟并 warn。含回退顺序测试。

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

apps/pac-service/src/modules/sync/pipeline/transaction-synthesizer.ts

@@ -98,13 +98,21 @@ export class TransactionSynthesizer {
       ? input.patientIdResolver(patientExternalId)
       : undefined;
 
-    // occurredAt — 从 yaml emits.occurredAtField 指定的字段拿
-    const occurredAt = this.pickOccurredAt(c, emits.occurredAtField);
+    // occurredAt — 从 yaml emits.occurredAtField 指定的字段拿;
+    // 缺失/不可解析时确定性回退 updatedAt → createdAt(与 sourceEventId 的 updatedAtMark 同序)。
+    // 墙钟只在三者皆缺时兜底:否则同一源行每次摄入 occurredAt 抖动,
+    // 下游 fact 时间锚变更检测会产生伪 supersede 版本。
+    let occurredAt = this.pickOccurredAt(c, emits.occurredAtField);
+    if (!occurredAt) {
+      occurredAt =
+        this.pickOccurredAt(c, 'updatedAt') ?? this.pickOccurredAt(c, 'createdAt');
+    }
     if (!occurredAt) {
       this.logger.warn(
         `Cannot determine occurredAt from field="${emits.occurredAtField}" ` +
-          `for ${input.resource} externalId=${subjectId};using now()`,
+          `(updatedAt/createdAt 亦缺)for ${input.resource} externalId=${subjectId};using now()`,
       );
+      occurredAt = new Date();
     }
 
     // sourceEventId 幂等键
@@ -128,7 +136,7 @@ export class TransactionSynthesizer {
       rawPayload: input.rawRow as Prisma.InputJsonValue,
       canonicalPayload: input.canonicalRow as Prisma.InputJsonValue,
       payloadHash,
-      occurredAt: occurredAt ?? new Date(),
+      occurredAt,
     };
   }
 

apps/pac-service/tests/transaction-synthesizer-occurred-at.spec.ts

+/**
+ * TransactionSynthesizer occurredAt 三级确定性回退单元测试。
+ *
+ * 坐实:emits.occurredAtField 缺失/不可解析时,回退 updatedAt → createdAt,
+ * 仅三者皆缺才落墙钟。否则同一源行(新 sourceEventId、时间字段为空)每次摄入
+ * 得到不同 occurredAt,下游 fact 时间锚变更检测会产生伪 supersede 版本。
+ */
+import { TransactionSynthesizer } from '../src/modules/sync/pipeline/transaction-synthesizer';
+import type { EmitsConfig } from '../src/modules/sync/assembler/assembler.schema';
+
+describe('synthesizer | occurredAt 确定性回退', () => {
+  const synth = new TransactionSynthesizer();
+  const emits: EmitsConfig = {
+    action: 'appointment_created',
+    subjectType: 'appointment',
+    occurredAtField: 'occurredAt',
+  };
+  const make = (canonicalRow: Record<string, unknown>) => ({
+    rawRow: {},
+    emits,
+    resource: 'appointments',
+    hostId: 'h1',
+    tenantId: 'grp_001',
+    patientIdResolver: () => undefined,
+    sourceContext: 'test:occurred-at',
+    sourceUnit: '',
+    canonicalRow: { externalId: 'apt-1', clinicId: 'C001', ...canonicalRow },
+  });
+
+  test('occurredAtField 有值 → 直接用,不看 updatedAt/createdAt', () => {
+    const tx = synth.synthesize(
+      make({
+        occurredAt: '2026-01-01T10:00:00+08:00',
+        updatedAt: '2026-02-01T00:00:00+08:00',
+        createdAt: '2026-03-01T00:00:00+08:00',
+      }),
+    );
+    expect(tx!.occurredAt).toEqual(new Date('2026-01-01T10:00:00+08:00'));
+  });
+
+  test('occurredAtField 缺失 → 回退 updatedAt', () => {
+    const tx = synth.synthesize(
+      make({
+        updatedAt: '2026-02-01T00:00:00+08:00',
+        createdAt: '2026-03-01T00:00:00+08:00',
+      }),
+    );
+    expect(tx!.occurredAt).toEqual(new Date('2026-02-01T00:00:00+08:00'));
+  });
+
+  test('occurredAtField 不可解析 → 回退 updatedAt', () => {
+    const tx = synth.synthesize(
+      make({
+        occurredAt: 'not-a-date',
+        updatedAt: '2026-02-01T00:00:00+08:00',
+      }),
+    );
+    expect(tx!.occurredAt).toEqual(new Date('2026-02-01T00:00:00+08:00'));
+  });
+
+  test('occurredAtField/updatedAt 皆缺 → 回退 createdAt', () => {
+    const tx = synth.synthesize(make({ createdAt: '2026-03-01T00:00:00+08:00' }));
+    expect(tx!.occurredAt).toEqual(new Date('2026-03-01T00:00:00+08:00'));
+  });
+
+  test('时间字段有值 → 重复摄入 occurredAt 逐字节一致(确定性,不受墙钟影响)', () => {
+    const row = { updatedAt: '2026-02-01T00:00:00+08:00' };
+    const a = synth.synthesize(make(row));
+    const b = synth.synthesize(make(row));
+    expect(a!.occurredAt).toEqual(b!.occurredAt);
+  });
+
+  test('三者皆缺 → 落墙钟兜底(列非空,不能是 null)', () => {
+    const before = Date.now();
+    const tx = synth.synthesize(make({}));
+    const after = Date.now();
+    expect(tx!.occurredAt).toBeInstanceOf(Date);
+    const t = (tx!.occurredAt as Date).getTime();
+    expect(t).toBeGreaterThanOrEqual(before);
+    expect(t).toBeLessThanOrEqual(after);
+  });
+});