targo-backend/src/modules/attachments/services/disk-storage.service.ts

60 lines
2.2 KiB
TypeScript

import { Injectable } from '@nestjs/common';
import { createHash } from 'node:crypto';
import { promises as fsp } from 'node:fs';
import { createWriteStream, statSync, existsSync } from 'node:fs';
import { join, dirname } from 'node:path';
import { pipeline } from 'node:stream/promises';
import { ATT_TMP_DIR } from 'src/config/attachment.config';
import { casPathFor, getAbsolutePath } from 'src/modules/attachments/utils/cas.util';
export type SaveResult = { sha256: string, storage_path: string, size: number };
@Injectable()
export class DiskStorageService {
// async exists(storagePathRel: string) {
// try {
// statSync(getAbsolutePath(storagePathRel));
// return true;
// } catch {
// return false;
// }
// }
//adds file and hash it
async saveStreamAndHash(input: NodeJS.ReadableStream): Promise<SaveResult> {
// 1- writing in ROOT:/_tmp while streaming and hashing
const tmpDir = ATT_TMP_DIR();
await fsp.mkdir(tmpDir, { recursive: true });
const tmpPath = join(tmpDir, `up_${Date.now()}_${Math.random().toString(36).slice(2)}`);
const hash = createHash('sha256');
const tmpOut = createWriteStream(tmpPath);
input.on('data', (chunk) => hash.update(chunk));
await pipeline(input, tmpOut); //await end of writing stream
const sha = hash.digest('hex');
const rel = casPathFor(sha);
const finalAbs = getAbsolutePath(rel);
// 2- is there is no destination => move (atomic renaming on the same volume)
if (!existsSync(finalAbs)) {
await fsp.mkdir(dirname(finalAbs), { recursive: true });
try {
await fsp.rename(tmpPath, finalAbs);
} catch (e) {
//if someone is faster and used the same hash
if (existsSync(finalAbs)) {
await fsp.rm(tmpPath, { force: true });
} else {
throw e;
}
}
} else {
//remove duplicata if already exists
await fsp.rm(tmpPath, { force: true });
}
const size = statSync(finalAbs).size;
return { sha256: sha, storage_path: rel, size };
}
}