Data Transfer Objects (DTOs) with Kawkab

A Data Transfer Object (DTO) is an object used to transfer data between different layers of your application in an organized and flexible way. With Kawkab, you can easily create DTOs and use them to manage incoming request data or data passed between different parts of your application.

Creating a New DTO with Kawkab

To create a new DTO, run the following command:

npm run kawkab dto:make <name> [module]

Parameter Details:

<name>: The name of the DTO you want to create (e.g., User).
[module]: The name of the module that contains the DTO (optional, default is main).

Practical Example:

npm run kawkab dto:make user

Result of Execution:

A DTO object named UserDTO will be created in the main module.
You can now easily use this DTO in your application.

How to Use DTO in Your Application

Once the DTO object is created, you can import and use it within your project files.

Importing the DTO:

To use the DTO, import it as shown below:

import { UserDTO } from "../dto/user";

Creating a DTO Object:

You can create a DTO object in three ways:

1. Creating the Object Without Passing Data:

When no data is passed, the DTO object will automatically fetch the data from the request:

const dto = new UserDTO();
console.log(dto.data); // Contains data from the current request

2. Passing Data Directly When Creating the Object:

You can pass data manually when creating the object:

const dto = new UserDTO({
    email: "hassan@example.com",
});
console.log(dto.data); // Contains { email: "hassan@example.com" }

DTO File Content:

The created UserDTO file will contain the following code:

import { BaseDTO, rule as r, req } from "kawkab";
 
export interface Item {
    [key: string]: any;
}
 
export class UserDTO extends BaseDTO {
    constructor(data: Item = req.inputs()) {
        super();
        this.dto(this, data);
    }
 
    static inject(data: Item = req.inputs()) {
        return { ...new this(data) };
    }
 
    data(i: Item): object {
        return {
            email: i?.email,
        };
    }
 
    rules() {
        return {
            email: r.string().email(),
        };
    }
}

Additional Notes

Data Validation:
- You can define validation rules using the rules() method. In the above example, a validation rule for the email field is defined.
Default Data Fetching:
- If no data is passed during object creation, request data is automatically fetched using req.inputs().
Organizing Data:
- You can define the final structure of the data via the data() method.

Conclusion

Kawkab provides a flexible way to create Data Transfer Objects (DTOs) to organize and validate data easily. By using this approach, you can improve your application’s code and separate data logic from business logic. Take advantage of this feature to build more stable and organized applications.

Localization Enums