How to use mongoose.isValidObjectId as a middleware in nestjs? - node.js

Question

I have an issue with repetitive requests for checking an Order id, if it is valid ObjectId or not. I got this error:
CastError: Cast to ObjectId failed for value "629b9fbd620dbc419a52e8" (type string) at path "_id" for model "Order"
After a lot of Googling, I found two approaches to tackle the problem, however I'll have to duplicate these codes for each service, which isn't a good idea.
First approach:
if (!mongoose.Types.ObjectId.isValid(req.params.id)) {
throw new HttpException('Not a valid ObjectId!', HttpStatus.NOT_FOUND);
} else {
return id;
}
Second approach:
if (!mongoose.isValidObjectId(req.params.id)) {
throw new BadRequestException('Not a valid ObjectId');
} else {
return id;
}
I used below codes for making and using a middleware, thus I could check ID whenever a service using an id parameter.
validateMongoID.ts
import {
BadRequestException,
Injectable,
NestMiddleware,
} from '#nestjs/common';
import { Request, Response, NextFunction } from 'express';
import mongoose from 'mongoose';
#Injectable()
export class IsValidObjectId implements NestMiddleware {
use(req: Request, res: Response, next: NextFunction) {
// Validate Mongo ID
if (req.params.id) {
if (!mongoose.isValidObjectId(req.params.id)) {
throw new BadRequestException('Not a valid ObjectId');
}
}
next();
}
}
orders.module.ts
export class OrdersModule implements NestModule {
configure(consumer: MiddlewareConsumer) {
consumer.apply(IsValidObjectId).forRoutes('/');
}
}
After trying as a middleware in the orders.modules.ts, I got the same error mentioned above. So, any idea to use it as a middleware?

Answer 1

I had to do this exact thing a couple of weeks ago.
Here is my solution. Works perfectly fine. Not a middleware, though.
id-param.decorator.ts
import { ArgumentMetadata, BadRequestException, Param, PipeTransform } from '#nestjs/common';
import { Types } from 'mongoose';
class ValidateMongoIdPipe implements PipeTransform<string> {
transform(value: string, metadata: ArgumentMetadata) {
if (!Types.ObjectId.isValid(value)) {
throw new BadRequestException(`${metadata.data} must be a valid MongoDB ObjectId`);
}
return value;
}
}
export const IdParam = (param = '_id'): ParameterDecorator => (
Param(param, new ValidateMongoIdPipe())
);
Usage
// If param is called _id then the argument is optional
#Get('/:_id')
getObjectById(#IdParam() _id: string) {
return this.objectsService.getById(_id);
}
#Get('/:object_id/some-relation/:nested_id')
getNestedObjectById(
#IdParam('object_id') objectId: string,
#IdParam('nested_id') nestedId: string,
) {
return this.objectsService.getNestedById(objectId, nestedId);
}
How it works
When using the #Param decorator you can give it transform pipes that will validate and mutate incoming value.
#IdParam decorator is just a #Param with the ValidateMongoIdPipe provided as a second argument.

Answer 2

I have found another way to solve it with the help of Lhon (tagged in comments).
create a file (I named it globalErrorHandler.ts) as follows:
import {
ArgumentsHost,
ExceptionFilter,
HttpException,
HttpStatus,
InternalServerErrorException,
} from '#nestjs/common';
export class AllExceptionsFilter implements ExceptionFilter {
catch(exception: InternalServerErrorException, host: ArgumentsHost) {
const ctx = host.switchToHttp();
const response = ctx.getResponse();
const request = ctx.getRequest();
const status =
exception instanceof HttpException
? exception.getStatus()
: HttpStatus.INTERNAL_SERVER_ERROR;
/**
* #description Exception json response
* #param message
*/
const responseMessage = (type, message) => {
response.status(status).json({
statusCode: status,
path: request.url,
errorType: type,
errorMessage: message,
});
};
// Throw an exceptions for either
// MongoError, ValidationError, TypeError, CastError and Error
if (exception.message) {
const newmsg: any = exception;
responseMessage(
'Error',
newmsg.response?.message ? newmsg.response.message : exception.message,
);
} else {
responseMessage(exception.name, exception.message);
}
}
}
add below line to main.ts
app.useGlobalFilters(new AllExceptionsFilter());
create another file (I named it validateMongoID.ts) as follows:
import {
BadRequestException,
Injectable,
NestMiddleware,
} from '#nestjs/common';
import { Request, Response, NextFunction } from 'express';
#Injectable()
export class IsValidObjectId implements NestMiddleware {
async use(req: Request, res: Response, next: NextFunction) {
// Validate Mongo ID
if (req.params.id) {
if (!/^[a-fA-F0-9]{24}$/.test(req.params.id)) {
throw new BadRequestException('Not a valid ObjectId');
}
}
next();
}
}
last step: import it as a middleware in app.module.ts
export class AppModule implements NestModule {
configure(consumer: MiddlewareConsumer) {
consumer.apply(IsValidObjectId).forRoutes('*');
}
}