[Microservices] the gRPC DTO is undefined if a param decorator is used

[twister21]

Bug Report

Current behavior

If a param decorator is applied to a parameter of a gRPC route handler, the DTO is always undefined, but the parameter the custom decorator is applied to gets populated properly.

Input Code

// controller

@GrpcMethod('ReportService')
createReport(createReportDto: CreateReportDto, @AuthUser() user: User): Promise<Report> {
  console.log(createReportDto); // undefined
  console.log(user) // {id: 1, role: 2}

  return this.reportService.createOne(createReportDto, user.id);
}

// param decorator

export const AuthUser = createParamDecorator(
  (data: any, context: ExecutionContext) => {
    const metadata = context.switchToRpc().getContext();
    return metadata.user; // the user is attached to the context in a guard
  },
);

Expected behavior

Both the DTO and the parameter that the decorator is applied to, should be populated properly.

Environment

Nest version: 7.1.0

[kamilmysliwiec]

Have you tried using @Payload() createReportDto: CreateReportDto?

[twister21]

That works. I did not see that there is a separate param decorator for a gRPC handler.

However, it seems that the @Body() decorator also works for the gRPC handler, since I'm trying to use the same handler for HTTP + gRPC.

Is this the intended behavior?

[kamilmysliwiec]

I'm glad it fixed your issue!

However, it seems that the @Body() decorator also works for the gRPC handler, since I'm trying to use the same handler for HTTP + gRPC.

This is due to the backward compatibility.

We gotta improve the documentation. Sorry for the inconvenience!

[danias]

What about metadata and call? When I use a decorator, data shows up when I use @payload() but I don't know what to use for metadata and call.

[MaksymShuldiner]

@kamilmysliwiec @danias agree, what argument should be used for metadata and call?