fix: hydrate durable registry snapshots before serving writes

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packages/registry/src/object-snapshot.test.tsadded+83-0

Changes to packages/registry/src/object-snapshot.test.ts

		@@ -0,0 +1,83 @@
	1	+import type { S3Client } from './storage/aws-client'
	2	+import { describe, expect, it } from 'bun:test'
	3	+import { S3RequestError } from './storage/aws-client'
	4	+import { ObjectSnapshot } from './storage/object-snapshot'
	5	+import { ObjectMetadataStorage } from './storage/object-metadata'
	6	+import { ObjectAnalytics } from './storage/object-analytics'
	7	+
	8	+function bucket(body: string, failure?: Error) {
	9	+ let reads = 0
	10	+ let writes = 0
	11	+ const client = {
	12	+ async getObjectBuffer() {
	13	+ reads++
	14	+ if (failure) throw failure
	15	+ return Buffer.from(body)
	16	+ },
	17	+ async putObject() { writes++ },
	18	+ } as unknown as S3Client
	19	+ return { client, reads: () => reads, writes: () => writes }
	20	+}
	21	+
	22	+describe('snapshot hydration safety', () => {
	23	+ for (const failure of [
	24	+ new S3RequestError('GET', 503, 'ServiceUnavailable'),
	25	+ new S3RequestError('GET', 403, 'AccessDenied'),
	26	+ new S3RequestError('GET', 404, 'NoSuchBucket'),
	27	+ new Error('transport unavailable'),
	28	+ new Error('adapter failed: 404 Not Found'),
	29	+ ]) {
	30	+ it(`rejects ${failure.message} without overwriting remote state`, async () => {
	31	+ const remote = bucket('{"existing":true}', failure)
	32	+ const snapshot = new ObjectSnapshot(remote.client, 'b', 'snapshot.json', () => ({}))
	33	+ await expect(snapshot.load()).rejects.toBe(failure)
	34	+ await expect(snapshot.flush()).rejects.toThrow()
	35	+ expect(remote.writes()).toBe(0)
	36	+ })
	37	+ }
	38	+
	39	+ it('cannot flush before the initial read completes', async () => {
	40	+ const remote = bucket('{}')
	41	+ const snapshot = new ObjectSnapshot(remote.client, 'b', 'snapshot.json', () => ({}))
	42	+ await expect(snapshot.flush()).rejects.toThrow()
	43	+ expect(remote.reads()).toBe(0)
	44	+ expect(remote.writes()).toBe(0)
	45	+ await snapshot.load()
	46	+ await snapshot.flush()
	47	+ expect(remote.writes()).toBe(1)
	48	+ })
	49	+
	50	+ it('permits a first save only after confirmed object absence', async () => {
	51	+ const remote = bucket('', new S3RequestError('GET', 404, 'NoSuchKey'))
	52	+ const snapshot = new ObjectSnapshot(remote.client, 'b', 'snapshot.json', () => ({}))
	53	+ expect(await snapshot.load()).toBeNull()
	54	+ await snapshot.flush()
	55	+ expect(remote.writes()).toBe(1)
	56	+ })
	57	+
	58	+ it('rejects corrupt snapshots without replacing them', async () => {
	59	+ for (const body of ['', '{broken']) {
	60	+ const remote = bucket(body)
	61	+ const snapshot = new ObjectSnapshot(remote.client, 'b', 'snapshot.json', () => ({}))
	62	+ await expect(snapshot.load()).rejects.toThrow()
	63	+ await expect(snapshot.flush()).rejects.toThrow()
	64	+ expect(remote.writes()).toBe(0)
	65	+ }
	66	+ })
	67	+
	68	+ it('metadata readiness rejects an outage and flush cannot overwrite the index', async () => {
	69	+ const remote = bucket('{}', new S3RequestError('GET', 503, 'ServiceUnavailable'))
	70	+ const storage = new ObjectMetadataStorage(remote.client, 'b')
	71	+ await expect(storage.ready()).rejects.toThrow('503')
	72	+ await expect(storage.flush()).rejects.toThrow()
	73	+ expect(remote.writes()).toBe(0)
	74	+ })
	75	+
	76	+ it('analytics readiness rejects an outage and flush cannot overwrite counters', async () => {
	77	+ const remote = bucket('{}', new S3RequestError('GET', 503, 'ServiceUnavailable'))
	78	+ const storage = new ObjectAnalytics(remote.client, 'b')
	79	+ await expect(storage.ready()).rejects.toThrow('503')
	80	+ await expect(storage.flush()).rejects.toThrow()
	81	+ expect(remote.writes()).toBe(0)
	82	+ })
	83	+})