Using Typescript interface as a variable
I am working on a Node Js (TypeScript) architecture and for some reason, I want to bind my interface to a specific object. I am making a general class that is extended by other subclasses and it will have a very general code. So my code looks like
interface User {
name: string;
}
interface Profile {
title: string;
}
class Parent {
name: string;
interface: Interface; // Help required here, getting error can't use type as a variable
constructor( name, interface ) {
// Load schema and store here
this.name = name
this.interface = interface
}
// Though this is not correct I hope you get the idea of what I am trying to do
get (): this.interface {
// fetch the data and return
return data
}
set (data: this.interface): void {
// adding new data
}
}
class UserSchema extends Parent {
// Class with custom functions for UserSchema
}
class ProfileSchema extends Parent {
// Class with custom functions for ProfileSchema
}
// Config file that saves the configs for different modules
const moduleConfig = [
{
name: "User Module",
class: UserSchema,
interface: User
},
{
name: "Profile Module",
class: ProfileSchema,
interface: Profile
},
]
const allModules = {}
// Loading the modules
moduleConfig.map(config => {
allModules[config.name] = new config.class(
config.name,
config.interface
)
})
export allModules;
I need suggestions on how should I bind my interfaces with their respective configs. Till now I have had no luck with that.
PS: All this code is separated into their respective files.
Solution 1:
This is the use case for generics. You can even see them as "variable for types".
Instead of having an interface
property in your Parent
class, the latter would have a generic type:
class Parent<T> { // T is the generic type
name: string;
// interface: Interface; // generic is already provided at class level
constructor( name ) {
// Load schema and store here
this.name = name
}
get (): T {
// fetch the data and return
return data
}
set (data: T): void {
// adding new data
}
}
// Here you specify the concrete generic type
class UserSchema extends Parent<User> {
// Class with custom functions for UserSchema
}
class ProfileSchema extends Parent<Profile> {
// Class with custom functions for ProfileSchema
}