Files
FileHost/server/utils/site-sync/chunks.ts
T
2026-10-17 18:15:42 +08:00

351 lines
10 KiB
TypeScript

import { createHash } from 'node:crypto'
import { promises as fs } from 'node:fs'
import { join } from 'node:path'
import { getDataDir } from '../data-dir'
import { findUserByUsername } from '../db'
import { getBackendById } from '../storage/resolver'
import { putLocalFileAtomic } from '../storage/local'
import type { StoredImageMeta } from '../storage/types'
import { recordSiteSyncArtifact } from './artifacts'
export const SITE_SYNC_CHUNK_SIZE = 4 * 1024 * 1024
const CHUNK_ROOT = '.pichost-tmp/site-sync-chunks'
export interface SiteSyncChunkMetadata {
jobId: string
mediaKey: string
key: string
totalSize: number
totalChunks: number
ownerUsername: string | null
originalName: string
uploadedAt: string
contentType: string
mediaType: StoredImageMeta['mediaType']
conflictMode: 'skip' | 'overwrite'
backendId: string
updatedAt: string
}
interface StoredSession extends SiteSyncChunkMetadata {
created: boolean
}
function uploadIdFor(jobId: string, key: string): string {
return createHash('sha256')
.update(jobId)
.update('\0')
.update(key)
.digest('hex')
}
function sessionDir(uploadId: string): string {
return join(getDataDir(), CHUNK_ROOT, uploadId)
}
function metadataPath(uploadId: string): string {
return join(sessionDir(uploadId), 'session.json')
}
function chunkPath(uploadId: string, index: number): string {
return join(sessionDir(uploadId), `chunk-${String(index).padStart(6, '0')}.part`)
}
async function readSession(uploadId: string): Promise<StoredSession | null> {
try {
const raw = await fs.readFile(metadataPath(uploadId), 'utf8')
return JSON.parse(raw) as StoredSession
} catch {
return null
}
}
async function writeSession(
uploadId: string,
session: StoredSession
): Promise<void> {
const path = metadataPath(uploadId)
const temp = `${path}.${process.pid}.${Date.now()}.tmp`
await fs.writeFile(temp, JSON.stringify(session))
await fs.rename(temp, path)
}
export async function getSiteSyncChunkStatus(input: {
jobId: string
key: string
}): Promise<{
exists: boolean
complete: boolean
received: number[]
totalChunks: number
totalSize: number
}> {
const uploadId = uploadIdFor(input.jobId, input.key)
const session = await readSession(uploadId)
if (!session) {
return {
exists: false,
complete: false,
received: [],
totalChunks: 0,
totalSize: 0
}
}
const received: number[] = []
for (let index = 0; index < session.totalChunks; index++) {
try {
const stat = await fs.stat(chunkPath(uploadId, index))
if (stat.isFile()) received.push(index)
} catch {
// Missing chunks are exactly what the caller needs to send.
}
}
return {
exists: true,
complete: received.length === session.totalChunks,
received,
totalChunks: session.totalChunks,
totalSize: session.totalSize
}
}
async function ensureSession(
metadata: SiteSyncChunkMetadata
): Promise<{ uploadId: string, session: StoredSession }> {
const uploadId = uploadIdFor(metadata.jobId, metadata.key)
const existing = await readSession(uploadId)
if (existing) {
if (
existing.totalSize !== metadata.totalSize
|| existing.totalChunks !== metadata.totalChunks
|| existing.mediaKey !== metadata.mediaKey
) {
throw new Error('分块上传会话参数不一致')
}
return { uploadId, session: existing }
}
const backend = await getBackendById(metadata.backendId)
if (!backend) throw new Error('分块上传存储后端不存在')
const session: StoredSession = {
...metadata,
created: !await backend.head(metadata.key),
updatedAt: new Date().toISOString()
}
await fs.mkdir(sessionDir(uploadId), { recursive: true })
await writeSession(uploadId, session)
return { uploadId, session }
}
async function writeFileAtomic(path: string, bytes: Uint8Array): Promise<void> {
const temp = `${path}.${process.pid}.${Date.now()}.tmp`
await fs.writeFile(temp, bytes)
await fs.rename(temp, path)
}
export async function writeSiteSyncChunk(input: {
metadata: SiteSyncChunkMetadata
index: number
bytes: Uint8Array
}): Promise<{
received: number
totalChunks: number
complete: boolean
}> {
const { uploadId, session } = await ensureSession(input.metadata)
if (
!Number.isInteger(input.index)
|| input.index < 0
|| input.index >= session.totalChunks
) {
throw new Error('分块序号无效')
}
const start = input.index * SITE_SYNC_CHUNK_SIZE
const expectedSize = Math.min(
SITE_SYNC_CHUNK_SIZE,
session.totalSize - start
)
if (input.bytes.length !== expectedSize) {
throw new Error(`分块大小不一致:预期 ${expectedSize},实际 ${input.bytes.length}`)
}
await writeFileAtomic(chunkPath(uploadId, input.index), input.bytes)
session.updatedAt = new Date().toISOString()
await writeSession(uploadId, session)
let received = 0
for (let index = 0; index < session.totalChunks; index++) {
try {
await fs.access(chunkPath(uploadId, index))
received++
} catch {
// Keep counting.
}
}
return {
received,
totalChunks: session.totalChunks,
complete: received === session.totalChunks
}
}
async function concatenateChunks(
uploadId: string,
session: StoredSession
): Promise<string> {
const outputPath = join(sessionDir(uploadId), 'assembled.part')
const output = await fs.open(outputPath, 'w')
try {
for (let index = 0; index < session.totalChunks; index++) {
const input = await fs.open(chunkPath(uploadId, index), 'r')
try {
const stat = await input.stat()
let offset = 0
while (offset < stat.size) {
const length = Math.min(1024 * 1024, stat.size - offset)
const buffer = Buffer.allocUnsafe(length)
const { bytesRead } = await input.read(buffer, 0, length, offset)
if (!bytesRead) break
await output.write(buffer, 0, bytesRead)
offset += bytesRead
}
} finally {
await input.close()
}
}
await output.sync()
} finally {
await output.close()
}
return outputPath
}
export async function finalizeSiteSyncChunk(input: {
jobId: string
key: string
}): Promise<{ success: true, skipped: boolean }> {
const uploadId = uploadIdFor(input.jobId, input.key)
const session = await readSession(uploadId)
if (!session) throw new Error('分块上传会话不存在')
const status = await getSiteSyncChunkStatus(input)
if (!status.complete) {
throw new Error(`分块尚未上传完成:${status.received.length}/${session.totalChunks}`)
}
const backend = await getBackendById(session.backendId)
if (!backend) throw new Error('分块上传存储后端不存在')
const existing = await backend.head(session.key)
if (session.conflictMode === 'skip' && existing) {
await fs.rm(sessionDir(uploadId), { recursive: true, force: true })
return { success: true, skipped: true }
}
const assembledPath = await concatenateChunks(uploadId, session)
const stat = await fs.stat(assembledPath)
if (stat.size !== session.totalSize) {
throw new Error(`组装文件大小不一致:预期 ${session.totalSize},实际 ${stat.size}`)
}
recordSiteSyncArtifact({
jobId: session.jobId,
mediaKey: session.mediaKey,
key: session.key,
backendId: session.backendId,
created: session.created
})
const owner = session.ownerUsername
? findUserByUsername(session.ownerUsername)
: null
const meta: StoredImageMeta = {
originalName: session.originalName,
uploadedAt: session.uploadedAt,
contentType: session.contentType,
size: session.totalSize,
userId: owner?.id ?? null,
mediaType: session.mediaType
}
if (backend.type === 'local') {
await putLocalFileAtomic(session.key, assembledPath)
} else {
const chunks: Buffer[] = []
for (let index = 0; index < session.totalChunks; index++) {
chunks.push(await fs.readFile(chunkPath(uploadId, index)))
}
await backend.put(session.key, Buffer.concat(chunks), meta)
}
await fs.rm(sessionDir(uploadId), { recursive: true, force: true })
return { success: true, skipped: false }
}
export async function cleanupSiteSyncChunkSessions(
jobId: string
): Promise<number> {
const root = join(getDataDir(), CHUNK_ROOT)
let entries
try {
entries = await fs.readdir(root, { withFileTypes: true })
} catch {
return 0
}
let removed = 0
for (const entry of entries) {
if (!entry.isDirectory()) continue
const session = await readSession(entry.name)
if (session?.jobId !== jobId) continue
await fs.rm(sessionDir(entry.name), { recursive: true, force: true })
removed++
}
return removed
}
export async function cleanupExpiredSiteSyncChunkSessions(
maxAgeMs = 24 * 60 * 60 * 1000
): Promise<number> {
const root = join(getDataDir(), CHUNK_ROOT)
let entries
try {
entries = await fs.readdir(root, { withFileTypes: true })
} catch {
return 0
}
const cutoff = Date.now() - maxAgeMs
let removed = 0
for (const entry of entries) {
if (!entry.isDirectory()) continue
const session = await readSession(entry.name)
if (!session || new Date(session.updatedAt).getTime() > cutoff) continue
await fs.rm(sessionDir(entry.name), { recursive: true, force: true })
removed++
}
return removed
}
export async function hasSiteSyncChunkSession(
jobId: string,
key: string
): Promise<boolean> {
return Boolean(await readSession(uploadIdFor(jobId, key)))
}
export function isSiteSyncChunkMetadata(
value: unknown
): value is SiteSyncChunkMetadata {
if (!value || typeof value !== 'object') return false
const item = value as Record<string, unknown>
return typeof item.jobId === 'string'
&& typeof item.mediaKey === 'string'
&& typeof item.key === 'string'
&& Number.isInteger(item.totalSize)
&& Number(item.totalSize) > 0
&& Number.isInteger(item.totalChunks)
&& Number(item.totalChunks) > 0
&& typeof item.originalName === 'string'
&& typeof item.uploadedAt === 'string'
&& typeof item.contentType === 'string'
&& (item.mediaType === 'image'
|| item.mediaType === 'video'
|| item.mediaType === 'file')
&& (item.conflictMode === 'skip' || item.conflictMode === 'overwrite')
&& typeof item.backendId === 'string'
}