feat: Support cnpm nfs with aws s3 sdk

The following services may be available:
1. Aliyun OSS
2. Tencent Cloud COS
3. AWS S3

Author: hyunrealshadow

src/index.ts

@@ -0,0 +1,179 @@
+import * as fs from 'fs'
+import * as path from 'path'
+import ReadableStream = NodeJS.ReadableStream
+import { S3 } from 'aws-sdk'
+
+interface S3Config {
+  mode: 'public' | 'private'
+  accessKeyId: string
+  secretAccessKey: string
+  bucket: string
+  region: string
+  endpoint: string
+}
+
+interface UploadOptions {
+  key: string
+  size: number
+  shasum?: string
+  shasum256?: string
+}
+
+interface DownloadOptions {
+  timeout: number
+}
+
+function trimKey(key: string) {
+  return key ? key.replace(/^\//, '') : ''
+}
+
+class S3Wrapper {
+  s3: S3
+  config: S3Config
+
+  constructor(config: S3Config) {
+    this.config = config
+
+    this.s3 = new S3({
+      accessKeyId: config.accessKeyId,
+      secretAccessKey: config.secretAccessKey,
+      region: config.region,
+      endpoint: config.endpoint,
+    })
+  }
+
+  private async _upload(
+    file: string | ReadableStream,
+    options: UploadOptions,
+  ): Promise<any> {
+    const key = trimKey(options.key)
+
+    if (typeof file === 'string') {
+      file = fs.createReadStream(file)
+    }
+
+    try {
+      this.s3
+        .putObject({
+          Bucket: this.config.bucket,
+          Key: options.key,
+          Body: file,
+        })
+
+      if (this.config.mode === 'public') {
+        return {
+          url: `https://${this.config.bucket}.${this.config.endpoint}/${key}`,
+        }
+      } else {
+        return { key: key }
+      }
+    } catch (e) {
+      throw new Error(`Could not upload file to S3: ${e.message}`)
+    }
+  }
+
+  async upload(filePath: string, options: UploadOptions): Promise<any> {
+    return this._upload(filePath, options)
+  }
+
+  async uploadBuffer(
+    fileBuffer: ReadableStream,
+    options: UploadOptions,
+  ): Promise<any> {
+    return this._upload(fileBuffer, options)
+  }
+
+  async remove(key: string): Promise<any> {
+    const decodedKey = decodeURIComponent(trimKey(key))
+
+    this.s3
+      .headObject({
+        Bucket: this.config.bucket,
+        Key: decodedKey,
+      })
+      .promise()
+      .then(() => {
+        this.s3.deleteObject({
+          Bucket: this.config.bucket,
+          Key: decodedKey,
+        })
+      })
+      .catch(e => {
+        if (e.statusCode === 404) {
+          e.message = 'File Not Found'
+        }
+        throw new Error(`Could not remove file from S3: ${e.message}`)
+      })
+  }
+
+  async download(
+    key: string,
+    savePath: string,
+    options: DownloadOptions,
+  ): Promise<any> {
+    const decodedKey = decodeURIComponent(trimKey(key))
+
+    const folderPath = path.dirname(savePath)
+    if (!fs.existsSync(folderPath)) {
+      fs.mkdirSync(folderPath)
+    }
+
+    this.s3
+      .headObject({
+        Bucket: this.config.bucket,
+        Key: decodedKey,
+      })
+      .promise()
+      .then(() => {
+        this.s3
+          .getObject({
+            Bucket: this.config.bucket,
+            Key: decodedKey,
+          })
+          .createReadStream()
+          .pipe(fs.createWriteStream(savePath))
+      })
+      .catch(e => {
+        if (e.statusCode === 404) {
+          e.message = 'File Not Found'
+        }
+        throw new Error(`Could not retrieve file from S3: ${e.message}`)
+      })
+  }
+
+  async createDownloadStream(
+    key: string,
+    options: DownloadOptions,
+  ): Promise<any> {
+    const decodedKey = decodeURIComponent(trimKey(key))
+
+    return new Promise((resolve, reject) => {
+      this.s3
+        .headObject({
+          Bucket: this.config.bucket,
+          Key: decodedKey,
+        })
+        .promise()
+        .then(() => {
+          resolve(
+            this.s3
+              .getObject({
+                Bucket: this.config.bucket,
+                Key: decodedKey,
+              })
+              .createReadStream(),
+          )
+        })
+        .catch(e => {
+          if (e.statusCode === 404) {
+            e.message = 'File Not Found'
+          }
+          throw new Error(`Could not retrieve file from S3: ${e.message}`)
+        })
+    })
+  }
+}
+
+export function create(options: S3Config) {
+  return new S3Wrapper(options)
+}