Resolve guard

A resolve guard is a type of a router guard, as mentioned in Chapter 9, Design Authentication and Authorization. A resolve guard can load necessary data for a component by reading record IDs from route parameters, asynchronously load the data and have it ready by the time the component activates and initializes.

The major advantages for a resolve guard includes reusability of loading logic, reduction of boilerplate code, and also shedding dependencies, because the component can receive the data it needs without having to import any service:

1. Create a new user.resolve.ts class under user/user:

src/app/user/user/user.resolve.ts
import { Injectable } from '@angular/core'
import { Resolve, ActivatedRouteSnapshot } from '@angular/router'
import { UserService } from './user.service'
import { IUser } from './user'

@Injectable()
export...