feat(server): generate checksum for previous uploaded assets (#558)

* feat(server): generate checksum for previous uploaded assets

* fix(server): typo

server/apps/microservices/src/processors/generate-checksum.processor.ts

@@ -0,0 +1,69 @@
+import { AssetEntity } from '@app/database/entities/asset.entity';
+import { generateChecksumQueueName } from '@app/job';
+import { Process, Processor } from '@nestjs/bull';
+import { Logger } from '@nestjs/common';
+import { InjectRepository } from '@nestjs/typeorm';
+import { createHash } from 'node:crypto';
+import fs from 'node:fs';
+import { IsNull, Repository } from 'typeorm';
+
+// TODO: just temporary task to generate previous uploaded assets.
+@Processor(generateChecksumQueueName)
+export class GenerateChecksumProcessor {
+  constructor(
+    @InjectRepository(AssetEntity)
+    private assetRepository: Repository<AssetEntity>,
+  ) {}
+
+  @Process()
+  async generateChecksum() {
+    let hasNext = true;
+    let pageSize = 200;
+    let offset = 0;
+
+    while (hasNext) {
+      const assets = await this.assetRepository.find({
+        where: {
+          checksum: IsNull()
+        },
+        skip: offset,
+        take: pageSize,
+      });
+
+      if (!assets?.length) {
+        hasNext = false; // avoid using break
+      } else {
+        for (const asset of assets) {
+          try {
+            await this.generateAssetChecksum(asset);
+          } catch (err: any) {
+            Logger.error(`Error generate checksum ${err}`);
+          }
+        }
+
+        if (assets.length < pageSize) {
+          hasNext = false;
+        } else {
+          offset += pageSize;
+        }
+      }
+    }
+  }
+
+  private async generateAssetChecksum(asset: AssetEntity) {
+    if (!asset.originalPath) return;
+    if (!fs.existsSync(asset.originalPath)) return;
+
+    const fileReadStream = fs.createReadStream(asset.originalPath);
+    const sha1Hash = createHash('sha1');
+    const deferred = new Promise<Buffer>((resolve, reject) => {
+      sha1Hash.once('error', (err) => reject(err));
+      sha1Hash.once('finish', () => resolve(sha1Hash.read()));
+    });
+
+    fileReadStream.pipe(sha1Hash);
+    const checksum = await deferred;
+
+    await this.assetRepository.update(asset.id, { checksum });
+  }
+}