Error: write EOF

Hi, I’m developing a Rest API with Nest.js. I successfully converted it to a monolithic lambda with aws-serverless-express with the next code:

const binaryMimeTypes: string[] = ['application/octet-stream'];

let cachedServer: Server;

async function bootstrapServer(): Promise<Server> {
  if (!cachedServer) {
    const expressApp = express();
    const nestApp = await NestFactory.create(
      AppModule,
      new ExpressAdapter(expressApp)
    );
    nestApp.use(eventContext());
    nestApp.enableCors();
    await nestApp.init();
    cachedServer = createServer(expressApp, undefined, binaryMimeTypes);
  }
  return cachedServer;
}

export const handler: Handler = async (
  event: APIGatewayEvent,
  context: Context
) => {
  cachedServer = await bootstrapServer();
  return proxy(cachedServer, event, context, 'PROMISE').promise;
};

For development, I use serverless-offline and serverless-webpack.

When I try to send an image with multipart/form-data to the /upload controller, it throws me an error regardless of the image type. ** With other file types (like .txt or .env) it works as expected. Before moving the app to lambda, it worked without any issues.

Controller:

 @Post('upload')
 @UseInterceptors(AnyFilesInterceptor())
 async upload(@UploadedFiles() files: any) {
    console.log('photos', files);
  }

Sending text file:

files [ { fieldname: 'file',
    originalname: 'expretiments.js',
    encoding: '7bit',
    mimetype: 'application/javascript',
    buffer:
     <Buffer 2f 2f 20 63 6f 6e 73 74 20 67 63 64 20 3d 20 28 61 2c 20 62 29 20 3d 3e 20 7b 0d 0a 2f 2f 20 09 77 68 69 6c 65 28 62 29 20 7b 0d 0
a 2f 2f 20 09 09 69 ... >,
    size: 8537 } ]

Error log (sending .png):

[Nest] 8276   - 09/20/2019, 12:18:42 PM   [ExceptionsHandler] Unexpected end of multipart data +149ms
Error: Unexpected end of multipart data
    at D:\web\_projects\new-book-2-wheel\server\node_modules\dicer\lib\Dicer.js:62:28
    at process._tickCallback (internal/process/next_tick.js:61:11)
ERROR: aws-serverless-express connection error
{ Error: write EOF
    at WriteWrap.afterWrite (net.js:788:14) errno: 'EOF', code: 'EOF', syscall: 'write' }

What I tried:

• changing multer to express-form-data
• playing around with binaryMimeTypes passed to createServer()
• using aws-lambda-multipart-parser package

aws-serverless-express: 3.3.6 nodejs: v10.16.0 Current workaround: send images in base64 format

[shelooks16]

Although the setup above works during development, in deployment it causes images being broken. I upload images to S3. Local upload is OK, when deployed - corrupted.

According to this post: https://stackoverflow.com/a/41770688, API gateway needs additional configuration to process binaries. To make it more or less automated, I simply installed serverless-apigw-binary and put */* wildcard.

serverless.yml:

plugins:
  - serverless-apigw-binary

custom:
  apigwBinary:
    types:
      - '*/*' 

handler:

const binaryMimeTypes: string[] = [];

if (
  event.body &&
  event.headers['Content-Type'].includes('multipart/form-data') &&
  process.env.NODE_ENV !== 'production' // added
) {
  event.body = (Buffer.from(event.body, 'binary') as unknown) as string;
}

[calflegal]

I am also experiencing the above issue, but with audio files: Unexpected end of multipart data