How to use on model into another model

Question

I have two separated models name employee and user with some common data and a accountId to link each other. One record for each model is as below:

Employee
 _id:1639137618164

 name:"*****"
        
 sites:Array
 company:”Software”
 jobTitle: “Associate Software Engineer”
 email:"*****"
 phonesms:"1"
 phonevoice:"1"
 licenseNumber:""
 avatarStamp:0
 pined:false
 accountId: 1639129314021 //link attribute
 countryCodeSms:"US"
 countryCodeVoice:"US"
 inviteCode:"09611"
 emergencyRoles: Object
 invite: "booksRbUoSM"

and for User is

_id:1639129314021

firstName:"*** ***"

lastName:"****"
companyName:"SITS"
passwordReset:""
activated:true
accountId:1639129314021 // link attribute
siteId:-1
    
role:0
    
last:1639137913873
blocked:false
blockedtext:""
trialend:1640338913781
paytype:1
hashAccess:Array
emergencyEnabled:false
visitorTypes:Array
sitesLimit:2
manualCreation:false
username:"*************"
    
password:"**********************************"
    
email:"*********************"
passwordNotification:true
passwordLifecycle:1646906375986
isNewUser:true
listFeature:Object

I want to search from user model whether if any employee exists with that accountId or not, if there is employee associated with accountId, then add new employee with the available common data. otherwise not. How can i do this in loopback. I am stuck here!

Answer 1

In Loopback 4

Solution 1:

In your user controller where you have the access to the UserRepository

Assuming you know the accountId and the accountId only exists if you have an employee record you can have a method

@get('/users/{accountId})
async findUserWhoIsAnEmployee(@param.path.string('accountId') accountId: string){
 return this.userRepository.findOne({where: {accountId}})
}

Assuming you don't know the accountId...

You can access the employee repository in your UserController by passing it as an argument in the constructor function and finding the user, then checking in the Employee record. (Not optimal since two queries will be made on your DB)

export class UserController{
  constructor(
     @repository(UserRepository) public userRepository: UserRepository,
     @repository(EmployeeRepository) private employeeRepository: EmployeeRepository
  )
  // returns employee record or null if none
  @get('/users/{id}/employee-record)
  async findUserWhoIsAnEmployee(@param.path.string('id') id: string){
   const user = await this.userRepository.findById(id);
   return (!user) ? null : this.employeeRepository.findOne({where: {accountId: user.accountId}})
  }
}

Solution 2:

Where you have a relation between the User and Employee Model (hasOne, preferrably)

You can find that employee record on the user

// returns employee record of a user if exists 
@get('/users/{id})
async findUserWhoIsAnEmployee(@param.path.string('id') id: string){
 return this.userRepository.findById(id).employeeRecord()
}
//Where employeeRecord is a reference property on the user Model.