feat: 新增 GridFS 文件存储方式；

packages/app-server/src/config.ts

@@ -1,13 +1,17 @@
 import * as path from 'path'
 import * as dotenv from 'dotenv'
+
+/**
+ * parse environment vars from the `.env` file if existing
+ */
 dotenv.config()
 
 /**
- * 应用运行配置管理
+ * configuration management
  */
 export default class Config {
   /**
-   * 获取数据库连接配置
+   * mongodb connection configuration
    */
   static get db() {
     if (!process.env['DB']) {
@@ -21,12 +25,12 @@ export default class Config {
     return {
       database: process.env['DB'],
       uri: process.env['DB_URI'],
-      poolSize: (process.env['DB_POOL_LIMIT'] ?? 100) as number,
+      maxPoolSize: (process.env['DB_POOL_LIMIT'] ?? 10) as number,
     }
   }
 
   /**
-   * 指定服务端密钥，用于生成 token 
+   * the server secret salt, mainly used for generating tokens
    */
   static get SERVER_SECRET_SALT(): string {
     const secret_salt = process.env['SERVER_SECRET_SALT'] ?? process.env['SERVER_SALT']
@@ -36,40 +40,54 @@ export default class Config {
     return secret_salt
   }
 
-  // 本地上传文件存储目录
+  /**
+   * the root path of local file system driver, only used while `FILE_SYSTEM_DRIVER` equals to 'local'
+   */
   static get LOCAL_STORAGE_ROOT_PATH(): string {
     return process.env['LOCAL_STORAGE_ROOT_PATH'] ?? path.join(process.cwd(), "data")
   }
 
-  // 临时文件目录
+  /**
+   * the file system driver: 'local', 'gridfs'
+   */
+  static get FILE_SYSTEM_DRIVER(): string {
+    return process.env['FILE_SYSTEM_DRIVER'] ?? 'gridfs'
+  }
+
+  /**
+   * the `temp path`
+   */
   static get TMP_PATH(): string {
     const tmp_path = process.env['TMP_PATH'] ?? path.join(process.cwd(), "tmp")
     return tmp_path
   }
 
   /**
-   * 指定日志级别
+   * the logger level : 'fatal', 'error', 'warning', 'debug', 'info', 'trace'
    */
   static get LOG_LEVEL(): string {
     return process.env['LOG_LEVEL'] ?? (this.isProd ? 'info' : 'debug')
   }
 
   /**
-   * 指定服务监听端口号，缺省为 8000
+   * the serving port, default is 8000
    */
   static get PORT(): number {
     return (process.env.PORT ?? 8000) as number
   }
 
   /**
-   * 指定开启云函数日志: "always" | "debug" | "none"
+   * enable cloud function logging, default is `always`
+   * - `always` means that all cloud functions' execution will be logged
+   * - `debug` means that only logging for debug invokes
+   * - `never` no logging any case
    */
   static get ENABLE_CLOUD_FUNCTION_LOG(): string {
-    return (process.env.ENABLE_CLOUD_FUNCTION_LOG ?? 'debug')
+    return (process.env.ENABLE_CLOUD_FUNCTION_LOG ?? 'always')
   }
 
   /**
-   * 是否生产环境
+   * in production deploy or not
    */
   static get isProd(): boolean {
     return process.env.NODE_ENV === 'production'

packages/app-server/src/lib/globals/globals.ts

@@ -90,7 +90,7 @@ export class Globals {
    * @returns 
    */
   private static _createAccessor() {
-    const accessor = new MongoAccessor(Config.db.database, Config.db.uri, { directConnection: true, maxPoolSize: Config.db.poolSize })
+    const accessor = new MongoAccessor(Config.db.database, Config.db.uri, { directConnection: true, maxPoolSize: Config.db.maxPoolSize })
 
     accessor.setLogger(createLogger('db', 'warning'))
     accessor.init()

packages/app-server/src/lib/storage/local_file_storage.ts

@@ -8,9 +8,9 @@ export class LocalFileStorage implements FileStorageInterface {
   rootPath: string
   namespace: string
 
-  constructor(rootPath: string, namespace: string = 'default') {
+  constructor(rootPath: string, bucket: string = 'public') {
     this.rootPath = rootPath
-    this.namespace = namespace
+    this.namespace = bucket
   }
 
   /**
@@ -104,7 +104,7 @@ export class LocalFileStorage implements FileStorageInterface {
    * @param name 
    * @returns 
    */
-   checkSafeDirectoryName(name: string): boolean {
+  checkSafeDirectoryName(name: string): boolean {
     assert(typeof name === 'string', 'name must be a string')
 
     const reg = /^([0-9]|[A-z]|_|-){3,64}$/
@@ -118,7 +118,7 @@ export class LocalFileStorage implements FileStorageInterface {
     assert(typeof name === 'string', 'name must be a string')
     const reg = /^([0-9]|[A-z]|_|-|\.){3,64}$/
     return reg.test(name)
-   }
+  }
 
   /**
    * 生成文件名

packages/app-server/src/router/file/gridfs.ts

@@ -0,0 +1,105 @@
+
+import * as fs from 'fs'
+import * as express from 'express'
+import { GridFSBucket } from 'mongodb'
+import { Globals } from '../../lib/globals'
+import { checkFileOperationToken, FS_OPERATION } from './utils'
+
+
+export const GridFSHandlers = {
+  handleUploadFile,
+  handleDownloadFile
+}
+
+/**
+ * upload file to the gridfs
+ * @param {string} bucket the bucket of file to store into, for example if `bucket = public`, the file path would be `/public/xxx.png`
+ */
+async function handleUploadFile(req: express.Request, res: express.Response) {
+  const auth = req['auth']
+  const bucket_name = req.params.bucket
+
+  // check file operation token if bucket is not 'public'
+  if (bucket_name !== 'public') {
+    const [code, message] = checkFileOperationToken(bucket_name, req.query?.token as string, FS_OPERATION.CREATE)
+    if (code) {
+      return res.status(code).send(message)
+    }
+  }
+
+  // check given file
+  const file = req.file
+  if (!file) {
+    return res.status(422).send('file cannot be empty')
+  }
+
+  // create a local file system driver
+  const bucket = new GridFSBucket(Globals.accessor.db, { bucketName: bucket_name })
+
+  const stream = bucket.openUploadStream(file.filename, {
+    metadata: { original_name: file.originalname, created_by: auth?.uid, bucket: bucket_name, created_at: Date.now() },
+    contentType: file.mimetype
+  })
+
+
+  // save to gridfs
+  fs.createReadStream(file.path)
+    .pipe(stream as any)
+    .on('finish', () => {
+      res.send({
+        code: 0,
+        data: {
+          id: stream.id,
+          filename: stream.filename,
+          bucket: bucket_name,
+          contentType: file.mimetype
+        }
+      })
+    })
+    .on('error', (err: Error) => {
+      Globals.logger.error('upload file to gridfs stream occurred error', err)
+      res.status(500).send('internal server error')
+    })
+}
+
+
+/**
+ * download file from gridfs by pointed bucket name and filename
+ * @param {string} bucket the bucket of file to store into, for example if `bucket = public`, the file path would be `/public/xxx.png`
+ */
+async function handleDownloadFile(req: express.Request, res: express.Response) {
+
+  const { bucket: bucket_name, filename } = req.params
+
+  // check file operation token if bucket is not 'public'
+  if (bucket_name !== 'public') {
+    const [code, message] = checkFileOperationToken(bucket_name, req.query?.token as string, FS_OPERATION.READ)
+    if (code) {
+      return res.status(code).send(message)
+    }
+  }
+
+
+  try {
+
+    const bucket = new GridFSBucket(Globals.accessor.db, { bucketName: bucket_name })
+    const stream = bucket.openDownloadStreamByName(filename)
+
+    const files = await bucket.find({ filename: filename }).toArray()
+    const file = files.shift()
+    if (!file) {
+      return res.status(404).send('Not Found')
+    }
+
+    if (file?.contentType) {
+      res.contentType(file.contentType)
+    }
+
+    res.set('x-bucket', bucket_name)
+    res.set('x-uri', `/${bucket_name}/${filename}`)
+    return stream.pipe(res)
+  } catch (error) {
+    Globals.logger.error('get file info failed', error)
+    return res.status(404).send('Not Found')
+  }
+}