[FIXED] How to fix unhandled promise rejection warning in NestJS

Issue

I'm using NestJS for my backend angular project and I've put method. It was running fine before I install swagger but after I install swagger, I got a warning that saying unhandled promise rejection and it won't allow me to run.

It's working fine If I comment the code in controllers so I think there is a problem with async/await but not really sure how to fix it so I would be really appreciated if I can get any help or suggestion on how to fix this?

Controller

    @Put(':id')
    async updateHelpSubsection(@Body() newHelp: HelpSubsectionModule, @Param() params): Promise<HelpSubsectionModule> {
        try{
            let oldHelpData = await this.helpSubsectionService.getHelpSubsectionbyId(params.id)
            return this.helpSubsectionService.updateHelpSubsection(oldHelpData, newHelp);
        }catch(e) {
            console.log(e)
        }
    }

Services

    async updateHelpSection(updateHelp: HelpSectionEntity, newHelpData): Promise<HelpSectionEntity> {

        Object.keys(newHelpData).forEach((key) => {
            updateHelp[key] = newHelpData[key];
        });

        try {
            return await this.helpSectionRepo.save(updateHelp);
        } catch (err) {
            throw new HttpException({
                error: err
            }, HttpStatus.FORBIDDEN)
        }
    }

This is the warning I'm getting.

Solution

Please update this in the controller:

       @Put(':id')
       async updateHelpSubsection(@Body() newHelp: HelpSectionEntity, @Param() params): Promise< HelpSectionEntity> {
           try{
               let oldHelpData = await this.helpSubsectionService.getHelpSubsectionbyId(params.id)
               return this.helpSubsectionService.updateHelpSubsection(oldHelpData, newHelp);
           }catch(e) {
               console.log(e)
           }
       }

Modules are not allowed in the types in typescript.

Please replace HelpSubsectionModule with HelpSectionEntity.

Answered By - Praveen Kumar Palai

Answer Checked By - Mary Flores (PHPFixing Volunteer)