feat(server): compress database backups with pigz when it is installed (#32806)

(cherry picked from commit 97af09ca3cbd7f08ea033f176e777c9a9de8fdb5)

server/src/repositories/process.repository.spec.ts

@@ -27,6 +27,16 @@ describe(ProcessRepository.name, () => {
     });
   });
 
+  describe('isCommandAvailable', () => {
+    it('should find an executable on the PATH', async () => {
+      await expect(sut.isCommandAvailable('bash')).resolves.toBe(true);
+    });
+
+    it('should not find a missing executable', async () => {
+      await expect(sut.isCommandAvailable('immich-missing-command')).resolves.toBe(false);
+    });
+  });
+
   describe('createSpawnDuplexStream', () => {
     it('should work (drain to stdout)', async () => {
       const process = sut.spawnDuplexStream('bash', ['-c', 'exit 0']);

server/src/repositories/process.repository.ts

@@ -1,10 +1,27 @@
 import { Injectable } from '@nestjs/common';
 import { SpawnOptionsWithoutStdio, fork, spawn } from 'node:child_process';
+import { constants } from 'node:fs';
+import { access } from 'node:fs/promises';
+import { availableParallelism } from 'node:os';
+import path from 'node:path';
 import { Duplex } from 'node:stream';
 
 @Injectable()
 export class ProcessRepository {
   spawn = spawn;
+  availableParallelism = availableParallelism;
+
+  async isCommandAvailable(command: string): Promise<boolean> {
+    const directories = (process.env.PATH ?? '').split(path.delimiter).filter(Boolean);
+    const found = await Promise.all(
+      directories.map((directory) =>
+        access(path.join(directory, command), constants.X_OK)
+          .then(() => true)
+          .catch(() => false),
+      ),
+    );
+    return found.includes(true);
+  }
 
   spawnDuplexStream(command: string, args?: readonly string[], options?: SpawnOptionsWithoutStdio): Duplex {
     let isStdinClosed = false;

server/src/services/database-backup.service.spec.ts

@@ -16,6 +16,7 @@ describe(DatabaseBackupService.name, () => {
 
   beforeEach(() => {
     mocks = getMocks();
+    mocks.process.isCommandAvailable.mockResolvedValue(false);
     maintenanceHealthRepositoryMock = automock(MaintenanceHealthRepository, {
       args: [mocks.logger],
       strict: false,
@@ -228,6 +229,19 @@ describe(DatabaseBackupService.name, () => {
       expect(mocks.storage.rename).toHaveBeenCalled();
     });
 
+    it('should compress with gzip when pigz is not installed', async () => {
+      await sut.handleBackupDatabase();
+      expect(mocks.process.isCommandAvailable).toHaveBeenCalledWith('pigz');
+      expect(mocks.process.spawnDuplexStream).toHaveBeenLastCalledWith('gzip', ['--rsyncable']);
+    });
+
+    it('should compress with pigz on every available core when it is installed', async () => {
+      mocks.process.isCommandAvailable.mockResolvedValue(true);
+      mocks.process.availableParallelism.mockReturnValue(8);
+      await sut.handleBackupDatabase();
+      expect(mocks.process.spawnDuplexStream).toHaveBeenLastCalledWith('pigz', ['--rsyncable', '--processes', '8']);
+    });
+
     it('should fail if pg_dump fails', async () => {
       mocks.process.spawnDuplexStream.mockReturnValueOnce(mockDuplex()('pg_dump', 1, '', 'error'));
       await expect(sut.handleBackupDatabase()).rejects.toThrow('pg_dump non-zero exit code (1)');

server/src/services/database-backup.service.ts

@@ -236,6 +236,8 @@ export class DatabaseBackupService {
     const backupFilePath = path.join(StorageCore.getBaseFolder(StorageFolder.Backups), filename);
     const temporaryFilePath = `${backupFilePath}.tmp`;
 
+    const compression = await this.getCompressionCommand();
+
     let pgdump: Duplex | undefined;
     let gzip: Duplex | undefined;
 
@@ -247,7 +249,7 @@ export class DatabaseBackupService {
         },
       });
 
-      gzip = this.processRepository.spawnDuplexStream('gzip', ['--rsyncable']);
+      gzip = this.processRepository.spawnDuplexStream(compression.command, compression.args);
       const fileStream = this.storageRepository.createWriteStream(temporaryFilePath);
 
       await pipeline(pgdump, gzip, fileStream);
@@ -267,6 +269,15 @@ export class DatabaseBackupService {
     return backupFilePath;
   }
 
+  private async getCompressionCommand() {
+    if (await this.processRepository.isCommandAvailable('pigz')) {
+      const processes = this.processRepository.availableParallelism();
+      return { command: 'pigz', args: ['--rsyncable', '--processes', processes.toString()] };
+    }
+
+    return { command: 'gzip', args: ['--rsyncable'] };
+  }
+
   async uploadBackup(file: Express.Multer.File): Promise<void> {
     const backupsFolder = StorageCore.getBaseFolder(StorageFolder.Backups);
     const fn = basename(file.originalname);