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Angular 14 Reactive Forms Example

In this article, we will explore the Angular(14) reactive forms with an example.

Reactive Forms:

  • Angular reactive forms support model-driven techniques to handle the form's input values.
  • The reactive forms state is immutable, any form filed change creates a new state for the form.
  • Reactive forms are built around observable streams, where form inputs and values are provided as streams of input values, which can be accessed synchronously.
Some key notations that involve in reactive forms are like:
  • FormControl - each input element in the form is 'FormControl'. The 'FormControl' tracks the value and validation status of form fields.
  • FormGroup - Track the value and validate the state of the group of 'FormControl'.
  • FormBuilder - Angular service which can be used to create the 'FormGroup' or FormControl instance quickly.
  • Form Array - That can hold infinite form control, this helps to create dynamic forms.

Create An Angular(14) Application:

Let's create a sample Angular(14) application to accomplish our demo.
Command To Install Angular CLI
ng new name_of_your_app

Now install the bootstrap package
npm install bootstrap

Add bootstrap CSS and JS reference into the 'angular.json' file.

Create a sample angular component like 'jobportal'.
ng generate component jobportal


Now add the 'app-jobportal' element to 'app.component.html'.
src/app/app.component.html:
<app-jobportal></app-jobportal>

Register Reactive Form Module:

To use angular reactive forms we have to import 'ReactiveFormModule' to 'AppModule'.
src/app/app.module.ts:
import { ReactiveFormsModule } from '@angular/forms';
// existing code hidden for display purpose
@NgModule({
  imports: [
    ReactiveFormsModule
  ]
})
export class AppModule { }

Simple Form Using FormControl & FormGroup Instances Explicitly:

Let's create a basic reactive form using 'FormControl' & 'FormGroup' instances explicitly.
src/app/jobportal/jobportal.component.ts:
import { Component, OnInit } from '@angular/core';
import { FormControl, FormGroup } from '@angular/forms';

@Component({
  selector: 'app-jobportal',
  templateUrl: './jobportal.component.html',
  styleUrls: ['./jobportal.component.css'],
})
export class JobportalComponent implements OnInit {
  constructor() {}

  jobForm = new FormGroup({
    firstName: new FormControl(''),
    lastName: new FormControl(''),
  });

  preview: string = '';

  ngOnInit(): void {}

  save() {
    this.preview = JSON.stringify(this.jobForm.value);
  }
}
  • (Line: 12-15) Declared variable like 'jobForm' of type 'FormGroup'. The 'FormGroup' contains the collection 'FormControl'. The 'FormControl' is mapped to the HTML input element to set or get the form data. Here the 'FormControl' instance passed an empty string that specifies the initial value of our input fields is empty, you can pass any string as a default value if you need.
  • (Line: 17) Declared variable like 'preview', for our demo purpose this variable will be used to display the form data on submitting the form.
  • (Line: 21-23) Added method like 'Save()'. In real application we are going to save our form data by posting to API call. Here in our demo we simply preview the form data by assigning to 'preview' variable.
src/app/jobportal/jobportal.component.html:
<div class="container">
  <legend>Job Portal</legend>
  <div class="row">
    <div class="col col-md-8" style="overflow-y: scroll; max-height: 100vh">
      <form [formGroup]="jobForm" (ngSubmit)="save()">
        <div class="mb-3">
          <label for="firstName" class="form-label">First Name</label>
          <input
            type="text"
            class="form-control"
            id="firstName"
            formControlName="firstName"
          />
        </div>
        <div class="mb-3">
          <label for="lastName" class="form-label">Last Name</label>
          <input
            type="text"
            class="form-control"
            id="lastName"
            formControlName="lastName"
          />
        </div>
        <button type="submit" class="btn btn-primary">Submit</button>
      </form>
    </div>
    <div class="col col-md-4">
      <div style="position: fixed">{{ preview }}</div>
    </div>
  </div>
</div>
  • (Line: 5) On the form tag added '[FormGroup]' directive to which assigned our 'jobForm'. The '(ngSubmit)' event get raised when the submit button of form whose type 'submit'. Here registered our 'save()' method to '(ngSubmit)' event.
  • (Line: 12&21) Mapping the reactive form controller with input fields using the 'formControlName' attribute. So the form data can be stored in to the formcontrols.
  • (Line: 25) Added the form submit button and here button type should be 'submit'.
  • (Line: 28) Demo purpose showing the preview of submitted form.

Form Using FormBuilder Service:

Using FormBuilder we can simplify our reactive forms code, we no need to explicitly initialize 'FormGroup' or 'FormControl' instances.
src/app/jobportal/jobportal.component.ts:
import { Component, OnInit } from '@angular/core';
import { FormBuilder, FormControl, FormGroup } from '@angular/forms';

@Component({
  selector: 'app-jobportal',
  templateUrl: './jobportal.component.html',
  styleUrls: ['./jobportal.component.css'],
})
export class JobportalComponent implements OnInit {
  constructor(private fb: FormBuilder) {}

  jobForm = this.fb.group({
    firstName: [''],
    lastName: [''],
  })

  preview: string = '';

  ngOnInit(): void {}

  save() {
    this.preview = JSON.stringify(this.jobForm.value);
  }
}
  • (Line: 10) Injected the 'FormBuilder' service that loads from the '@angular/forms'.
  • (Line: 12-15) The 'group' method of 'FormBuilder' can create a new instance of 'FormGroup'. Here 'FormControl' also does not need to create explicitly. To the 'FormControl' property assigns the array as a value and the first value in the array will be the default value.

Nested FormGroup:

Reactive Forms supports nested or child form groups.

So let's implement the nested form group by grouping example form controls like 'Prefered Contact'(Dropdown), 'Email'(Text box), and 'Phone'(Text box).
src/app/jobportal/jobportal.component.ts:
jobForm = this.fb.group({
firstName: [''],
lastName: [''],
contacts: this.fb.group({
  contactType: ['-1'],
  email: [''],
  phone: [''],
}),
});
  • Here 'contacts' is our nested FromGroup that contains 'contactType', 'email', 'phone' as FormControls.
src/app/jobportal/jobportal.component.html:
<div class="container">
  <legend>Job Portal</legend>
  <div class="row">
    <div class="col col-md-8" style="overflow-y: scroll; max-height: 100vh">
      <form [formGroup]="jobForm" (ngSubmit)="save()">
        <div class="mb-3">
          <label for="firstName" class="form-label">First Name</label>
          <input
            type="text"
            class="form-control"
            id="firstName"
            formControlName="firstName"
          />
        </div>
        <div class="mb-3">
          <label for="lastName" class="form-label">Last Name</label>
          <input
            type="text"
            class="form-control"
            id="lastName"
            formControlName="lastName"
          />
        </div>
        <div class="mb-3" formGroupName="contacts">
          <div class="row">
            <div class="col col-md-4 offset-md-4">
              <div class="mb-3">
                <label class="form-label">Prefered Contact</label>
                <select
                  class="form-select"
                  formControlName="contactType"
                  aria-label="Default select example"
                >
                  <option value="-1">-select-</option>
                  <option value="email">Email</option>
                  <option value="phone">Phone</option>
                </select>
              </div>
            </div>
          </div>
          <div class="row">
            <div class="col col-md-6">
              <div class="mb-3">
                <label for="email" class="form-label">Email</label>
                <input
                  type="email"
                  class="form-control"
                  id="email"
                  formControlName="email"
                />
              </div>
            </div>
            <div class="col col-md-6">
              <div class="mb-3">
                <label for="phone" class="form-label">Phone</label>
                <input
                  type="text"
                  class="form-control"
                  id="phone"
                  formControlName="phone"
                />
              </div>
            </div>
          </div>
        </div>
        <button type="submit" class="btn btn-primary">Submit</button>
      </form>
    </div>
    <div class="col col-md-4">
      <div style="position: fixed">{{ preview }}</div>
    </div>
  </div>
</div>
  • (Line: 24-68) The nested form group HTML. Here nested form group name 'contacts' assigned to the 'formGroupName' attribute.
  • (Line: 30-37) The Dropdrown form control mapped to the 'contactType' with 'formControlName' attribute.
  • (Line: 45-50) The email input form control mapped to the 'email' with 'formControlName' attribute.
  • (Line: 56-61) The phone input form control mapped to the 'phone' with 'formControlName' attribute.

FormArray To Create Dynamic Forms:

Using FormArray we can create dynamic forms that can be infinite FormControls or FormGroups.

In our demo, we will add a button like 'Add A Skill', on clicking the button it will create a new FormGroup that contains FormControls like 'Programming Language' & 'Experience'.
src/app/jobportal/jobportal.component.ts:
import { Component, OnInit } from '@angular/core';
import { FormArray, FormBuilder } from '@angular/forms';

@Component({
  selector: 'app-jobportal',
  templateUrl: './jobportal.component.html',
  styleUrls: ['./jobportal.component.css'],
})
export class JobportalComponent implements OnInit {
  constructor(private fb: FormBuilder) {}

  jobForm = this.fb.group({
    firstName: [''],
    lastName: [''],
    contacts: this.fb.group({
      contactType: ['-1'],
      email: [''],
      phone: [''],
    }),
    skills: this.fb.array([]),
  });

  preview: string = '';

  ngOnInit(): void {}

  save() {
    this.preview = JSON.stringify(this.jobForm.value);
  }

  get skillsForms() {
    return this.jobForm.get('skills') as FormArray;
  }

  addASkillFormGroup() {
    this.skillsForms.push(
      this.fb.group({
        programLanguage: [''],
        experience: [0],
      })
    );
  }

  removeSkillFormGroup(index: number) {
    this.skillsForms.removeAt(index);
  }
}
  • (Line: 20) Defined the FormArray using the 'array()' method in 'FormBuilder' and it is assigned to the 'skills'. Initially, FormArray has empty controls
  • (Line: 31-33) Creating a get property like 'skillForms' of type FormArray. So using the property we can interact with 'skills' FormArray.
  • (Line: 35-42) The 'addASkillFormGroup()' method to add a new FormGroup into the FormArray. Here FormGroup contains FormControls like 'programLanguage', 'experience'.
  • (Line: 44-46) The 'removeSkillFormGroup()' method to remove a FormGroup from FromArray based on its index value.
src/app/jobportal/jobportal.component.html:
<div class="container">
  <legend>Job Portal</legend>
  <div class="row">
    <div class="col col-md-8" style="overflow-y: scroll; max-height: 100vh">
      <form [formGroup]="jobForm" (ngSubmit)="save()">
        <div class="mb-3">
          <label for="firstName" class="form-label">First Name</label>
          <input
            type="text"
            class="form-control"
            id="firstName"
            formControlName="firstName"
          />
        </div>
        <div class="mb-3">
          <label for="lastName" class="form-label">Last Name</label>
          <input
            type="text"
            class="form-control"
            id="lastName"
            formControlName="lastName"
          />
        </div>
        <div class="mb-3" formGroupName="contacts">
          <div class="row">
            <div class="col col-md-4 offset-md-4">
              <div class="mb-3">
                <label class="form-label">Prefered Contact</label>
                <select
                  class="form-select"
                  formControlName="contactType"
                  aria-label="Default select example"
                >
                  <option value="-1">-select-</option>
                  <option value="email">Email</option>
                  <option value="phone">Phone</option>
                </select>
              </div>
            </div>
          </div>
          <div class="row">
            <div class="col col-md-6">
              <div class="mb-3">
                <label for="email" class="form-label">Email</label>
                <input
                  type="email"
                  class="form-control"
                  id="email"
                  formControlName="email"
                />
              </div>
            </div>
            <div class="col col-md-6">
              <div class="mb-3">
                <label for="phone" class="form-label">Phone</label>
                <input
                  type="text"
                  class="form-control"
                  id="phone"
                  formControlName="phone"
                />
              </div>
            </div>
          </div>
        </div>
        <div class="mb-3" formArrayName="skills">
          <div class="row">
            <div class="col col-md-4 offset-md-4">
              <button
                type="button"
                (click)="addASkillFormGroup()"
                class="btn btn-primary"
              >
                Add A Skill
              </button>
            </div>
          </div>
          <ng-container
            *ngFor="let skillForm of skillsForms.controls; let i = index"
          >
            <div class="row" [formGroupName]="i">
              <div class="col col-md-5">
                <div class="mb-3">
                  <label [for]="'programLanguage' + i" class="form-label"
                    >Programing Language</label
                  >
                  <input
                    type="text"
                    class="form-control"
                    [id]="'programLanguage' + i"
                    formControlName="programLanguage"
                  />
                </div>
              </div>
              <div class="col col-md-5">
                <div class="mb-3">
                  <label [for]="'experience' + i" class="form-label"
                    >Experience</label
                  >
                  <input
                    type="text"
                    class="form-control"
                    [id]="'experience' + i"
                    formControlName="experience"
                  />
                </div>
              </div>
              <div class="col col md-2">
                <button
                  class="btn btn-danger mt-4"
                  type="button"
                  (click)="removeSkillFormGroup(i)"
                >
                  Delete
                </button>
              </div>
            </div>
          </ng-container>
        </div>
        <button type="submit" class="btn btn-primary">Submit</button>
      </form>
    </div>
    <div class="col col-md-4">
      <div style="position: fixed">{{ preview }}</div>
    </div>
  </div>
</div>
  • (Line: 66-129) Used FormArray to generate the dynamic form content.
  • (Line: 66) The 'formArrayName' attribute assigned mapped with 'skills'
  • (Line: 69-75) The 'Add A Skill' button rendered and its click event registered with the 'AddASkillFormGroup()' method.
  • (Line 78-80) The 'ng-container' is the imaginary angular element that can be used for implementing 'ngFor' or 'ngIf' by avoiding the additional 'div' tags. Here looping the 'skillsForm' getter controls to render the FormGroups. Here loop item index needs to be specified because the index value will be used as the value for the 'formGroupName' attribute.
  • (Line: 87-92)The programing language input form control mapped to the 'programLanguage' with 'formControlName' attribute.
  • (Line: 100-105) The experience input form control mapped to the 'experience' with 'formControlName' attribute.
  • (Line: 109-115) The 'Delete' button rendered and its click event registered with the 'removeSkillFromGroup()' method.

Reactive Forms 'setValue()':

In Reactive Forms 'setValue()' method is used to set the values to the entire form. This method is useful when we want to bind the API response to form data. But using 'setValue()' we can't update the form partially.
src/app/jobportal/jobportal.component.ts:
sampleSetValues() {
this.jobForm.setValue({
  firstName: 'naveen',
  lastName: 'Bommidi',
  contacts: {
	contactType: 'email',
	email: 'naveen@test.com',
	phone: '9876543210',
  },
  skills: [],
});
}
  • Created a method like 'sampleSetValues()' in that added logic to update the form using the 'setValue()' method.
For testing, purpose add a new button like 'Test setValue()' under the 'Submit' button. Register the click even to 'sampleSetValue()' method.
src/app/jobportal/jobportal.component.html:
<button type="button" class="btn btn-primary" (click)="sampleSetValues()">
Test SetValue()
</button>
Now click on the 'Test setValue()' button and the form gets populated with data as below.

Reactive Forms 'patchValue()':

In Reactive Forms to update partial form data, we can use the 'patchValue()' method.
src/app/jobportal/jobportal.component.ts:
samplePatchValues() {
this.jobForm.patchValue({
  firstName: 'naveen',
  contacts: {
	phone: '8908908901',
  },
});
}
Now add a button like 'Test PatchValue()' and register the click event with 'samplePatchValue()' method.
src/app/jobportal/jobportal.component.html:
<button type="button" class="btn btn-primary" (click)="samplePatchValues()">
Test PatchValue()
</button>

Reactive Forms Built-In Validation Function:

Reactive forms had several Built-in validation functions like maxlenght, minlength, required, email, etc.
src/app/jobportal/jobportal.component.ts:
import { Component, OnInit } from '@angular/core';
import { FormArray, FormBuilder, Validators } from '@angular/forms';
// existing code hidden for display purpose
@Component({
  selector: 'app-jobportal',
  templateUrl: './jobportal.component.html',
  styleUrls: ['./jobportal.component.css'],
})
export class JobportalComponent implements OnInit {
  constructor(private fb: FormBuilder) {}

  jobForm = this.fb.group({
    firstName: ['',[Validators.required]],
    lastName: [''],
    contacts: this.fb.group({
      contactType: ['-1'],
      email: [''],
      phone: [''],
    }),
    skills: this.fb.array([]),
  });


  get firstName(){
    return this.jobForm.get('firstName');
  }

}
  • Here 'firstName' controller is enabled with validation like 'Validators.required'(built-in validation method). The 'Validators' instance load from the '@angular/forms'
  • Created 'firstName()' getter to get the instance form controller of 'firsName'. This property is handy for applying the HTML condition for displaying errors
Just below the 'First Name' input field add the following error message display div's.
src/app/jobportal/jobportal.component.html:
<div
class="alert alert-danger"
*ngIf="
  firstName?.invalid && (firstName?.touched || firstName?.dirty)
"
>
<div *ngIf="firstName?.errors?.['required']">
  First Name can't be emtpy
</div>
</div>
  • Here 'firstName'(getter) we check like 'invalid'(satisfying the validation rules), 'touched'(input field touched or not), and 'dirty'(value inside of the input field changed or not). 
  • (Line: 7) Checking that the 'required' error message exists or not.

Custom Validator:

In reactive forms, we can implement our own custom logic validators.

For our demo 'Prefered Contact Type', I'm going to implement custom validators that fires if neither email nor phone is selected. Let's create a folder like 'shared' and a file like 'customerror.directive.ts'
src/app/shared/customerror.directive.ts:
import { AbstractControl, ValidationErrors, ValidatorFn } from '@angular/forms';

export function emailOrPhoneRequired(): ValidatorFn {
  return (control: AbstractControl): ValidationErrors | null => {
    return control.value == '-1'
      ? { emailOrPhoneRequired: { value: control.value } }
      : null;
  };
}
  • Here created method like 'emailorPhoneRequired()' of type 'ValidatorFn' that loads from the '@angular/forms'. Inside this  method, we return the arrow function of type 'ValidatonError' that loads from the '@angular/forms' and input parameter of type 'AbstracControl'. The 'AbstracControl' is nothing but the FormControl instance to which our custom validator applied
  • Here I'm checking like the FormControl value is "-1" then I'm returning an object that specifies it is invalid else I'm returning 'null' which means no error.
src/app/jobportal/jobportal.component.ts:
import { Component, OnInit } from '@angular/core';
import { FormArray, FormBuilder, Validators } from '@angular/forms';
import { emailOrPhoneRequired } from '../shared/customerror.directive';

@Component({
  selector: 'app-jobportal',
  templateUrl: './jobportal.component.html',
  styleUrls: ['./jobportal.component.css'],
})
export class JobportalComponent implements OnInit {
  constructor(private fb: FormBuilder) {}

  jobForm = this.fb.group({
    firstName: ['',[Validators.required]],
    lastName: [''],
    contacts: this.fb.group({
      contactType: ['-1',[emailOrPhoneRequired()]],
      email: [''],
      phone: [''],
    }),
    skills: this.fb.array([]),
  });

  get contactType(){
    return this.jobForm.get("contacts.contactType");
  }
}
  • (Line: 17) For 'contactType' FormCotnrol enabled the 'emailOrPhoneRequired()' custom validator.
  • (Line: 24-26) Created a getter for 'contacType' FromControl.
Now under the 'Prefered Contact' dropdown add the following error message divs
src/app/jobportal/jobportal.component.html:
<div
  class="alert alert-danger"
  *ngIf="
  contactType?.invalid &&
	(contactType?.touched || contactType?.dirty)
  "
>
  <div *ngIf="contactType?.errors?.['emailOrPhoneRequired']">
	Either email or phone need to selected
  </div>
</div>

Validation For FormArray:

In Reactive forms, we can apply both built-in or custom validation methods to FormArray.
app/src/jobportal/jobportal.componen.ts:
import { Component, OnInit } from '@angular/core';
import { FormArray, FormBuilder, Validators } from '@angular/forms';
import { emailOrPhoneRequired } from '../shared/customerror.directive';
// code hidden for display purpose
@Component({
  selector: 'app-jobportal',
  templateUrl: './jobportal.component.html',
  styleUrls: ['./jobportal.component.css'],
})
export class JobportalComponent implements OnInit {

  getProgramingLagnuage(index: number) {
    return this.skillsForms.at(index).get('programLanguage');
  }

  addASkillFormGroup() {
    this.skillsForms.push(
      this.fb.group({
        programLanguage: ['', [Validators.required]],
        experience: [0],
      })
    );
  }
}
  • (Line: 12-14) The 'skillForms' is FormArray so to get the FormControl inside of it we can't create a getter, so we created a normal function for that.
  • (LIne: 19) For 'programLanguage' FormControlled enabled with the 'Validator.required' validation function.
src/app/jobportal/jobportal.component.html:
<div
class="alert alert-danger"
*ngIf="
getProgramingLagnuage(i)?.invalid &&
  (getProgramingLagnuage(i)?.touched || getProgramingLagnuage(i)?.dirty)
"
>
<div *ngIf="getProgramingLagnuage(i)?.errors?.['required']">
  Known programing skill can't be empty
</div>
</div>

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Wrapping Up:

Hopefully, I think this article delivered some useful information on Angular 14 Reactive Forms. using I love to have your feedback, suggestions, and better techniques in the comment section below.

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Comments

  1. Your embedded ads are all extremely inappropriate for a site that will be accessed at work for professional software content.

    ReplyDelete
  2. Thank you for this helpful tutorial. I only have one question: how do I prevent the form from being sent when required fields aren't filled? In my example, the method in (ngSubmit) always gets executed even though required fields aren't filled.

    ReplyDelete
  3. pls use this code on save method
    save()
    {

    if(this.jobform.valid)
    {
    this.preview=JSON.stringify(this.jobform.value);
    }
    }

    ReplyDelete

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In this article, we are going to implement the Angular(14) state management CRUD example with NgRx(14) NgRx Store For State Management: In an angular application to share consistent data between multiple components, we use NgRx state management. Using NgRx state helps to avoid unwanted API calls, easy to maintain consistent data, etc. The main building blocks for the NgRx store are: Actions - NgRx actions represents event to trigger the reducers to save the data into the stores. Reducer - Reducer's pure function, which is used to create a new state on data change. Store - The store is the model or entity that holds the data. Selector - Selector to fetch the slices of data from the store to angular components. Effects - Effects deals with external network calls like API. The effect gets executed based the action performed Ngrx State Management flow: The angular component needs data for binding.  So angular component calls an action that is responsible for invoking the API call.  Aft

Angular 14 Crud Example

In this article, we will implement CRUD operation in the Angular 14 application. Angular: Angular is a framework that can be used to build a single-page application. Angular applications are built with components that make our code simple and clean. Angular components compose of 3 files like TypeScript File(*.ts), Html File(*.html), CSS File(*.cs) Components typescript file and HTML file support 2-way binding which means data flow is bi-directional Component typescript file listens for all HTML events from the HTML file. Create Angular(14) Application: Let's create an Angular(14) application to begin our sample. Make sure to install the Angular CLI tool into our local machine because it provides easy CLI commands to play with the angular application. Command To Install Angular CLI npm install -g @angular/cli Run the below command to create the angular application. Command To Create Angular Application ng new name_of_your_app Note: While creating the app, you will see a noti

Unit Testing Asp.NetCore Web API Using xUnit[.NET6]

In this article, we are going to write test cases to an Asp.NetCore Web API(.NET6) application using the xUnit. xUnit For .NET: The xUnit for .Net is a free, open-source, community-focused unit testing tool for .NET applications. By default .Net also provides a xUnit project template to implement test cases. Unit test cases build upon the 'AAA' formula that means 'Arrange', 'Act' and 'Assert' Arrange - Declaring variables, objects, instantiating mocks, etc. Act - Calling or invoking the method that needs to be tested. Assert - The assert ensures that code behaves as expected means yielding expected output. Create An API And Unit Test Projects: Let's create a .Net6 Web API and xUnit sample applications to accomplish our demo. We can use either Visual Studio 2022 or Visual Studio Code(using .NET CLI commands) to create any.Net6 application. For this demo, I'm using the 'Visual Studio Code'(using the .NET CLI command) editor. Create a fo

Part-1 Angular JWT Authentication Using HTTP Only Cookie[Angular V13]

In this article, we are going to implement a sample angular application authentication using HTTP only cookie that contains a JWT token. HTTP Only JWT Cookie: In a SPA(Single Page Application) Authentication JWT token either can be stored in browser 'LocalStorage' or in 'Cookie'. Storing JWT token inside of the cookie then the cookie should be HTTP Only. The HTTP-Only cookie nature is that it will be only accessible by the server application. Client apps like javascript-based apps can't access the HTTP-Only cookie. So if we use authentication with HTTP only JWT cookie then we no need to implement custom logic like adding authorization header or storing token data, etc at our client application. Because once the user authenticated cookie will be automatically sent to the server by the browser on every API call. Authentication API: To implement JWT cookie authentication we need to set up an API. For that, I had created a mock authentication API(Using the NestJS Se

ReactJS(v18) Authentication With JWT AccessToken And Refresh Token

In this article, we are going to do ReactJS(v18) application authentication using the JWT Access Token and Refresh Token. JSON Web Token(JWT): JSON Web Token is a digitally signed and secured token for user validation. The JWT is constructed with 3 important parts: Header Payload Signature Create ReactJS Application: Let's create a ReactJS application to accomplish our demo. npx create-react-app name-of-your-app Configure React Bootstrap Library: Let's install the React Bootstrap library npm install react-bootstrap bootstrap Now add the bootstrap CSS reference in 'index.js'. src/index.js: import 'bootstrap/dist/css/bootstrap.min.css' Create A React Component 'Layout': Let's add a React component like 'Layout' in 'components/shared' folders(new folders). src/components/shared/Layout.js: import Navbar from "react-bootstrap/Navbar"; import { Container } from "react-bootstrap"; import Nav from "react-boot

A Small Guide On NestJS Queues

NestJS Application Queues helps to deal with application scaling and performance challenges. When To Use Queues?: API request that mostly involves in time taking operations like CPU bound operation, doing them synchronously which will result in thread blocking. So to avoid these issues, it is an appropriate way to make the CPU-bound operation separate background job.  In nestjs one of the best solutions for these kinds of tasks is to implement the Queues. For queueing mechanism in the nestjs application most recommended library is '@nestjs/bull'(Bull is nodejs queue library). The 'Bull' depends on Redis cache for data storage like a job. So in this queueing technique, we will create services like 'Producer' and 'Consumer'. The 'Producer' is used to push our jobs into the Redis stores. The consumer will read those jobs(eg: CPU Bound Operations) and process them. So by using this queues technique user requests processed very fastly because actually