ngx-validation-framework

A policy based fluid model validation framework for Angular projects.

Demo

https://ngx-model-validator.web.app/simple

Installation

npm i ngx-model-validator --save

Usage

• Simple validation with error display on field

<ngx-component-validator [model]="person" [policy]="PERSON_POLICY_NAME" [policyFnRef]="PERSON_VALIDATION_FN"></ngx-component-validator>

<input matInput placeholder="First Name" ngxMatValidate [model]="person" validateProperty="firstName" [policy]="PERSON_POLICY_NAME" [(ngModel)]="person.firstName" />

import NgxValidationModule in app.module.ts

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { NgxValidationModule } from 'ngx-model-validator';

import { AppComponent } from './app.component';

@NgModule({
    imports: [BrowserModule, FormsModule, NgxValidationModule],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
})
export class AppModule {
}

// policy

import { NgxValidatorHelper , NgxValidationPolicy } from 'ngx-model-validator';

export class PersonValidationPolicy implements NgxValidationPolicy {

    addValidations(validatorHelper: NgxValidatorHelper): any[] {

        const lastNameValidatorFn = (model, ...args) => {
            
            if(model.firstName && model.firstName.length > 1) {
                return true;
            } else {
                return false;
            }
        }

        const cityAndStateAsyncValidatorFn = async(errorMsg:string, val :any, policy:any, model:any)=>{

            // api key get resets everyday - get new one while testing
            const api_key = "api_key";
            const url = `some_url/${api_key}`;
            const result = await (await fetch(url)).json();

            if(result){
                if(result.state === model.address.state) {
                    return true;
                }
            } 
            
            policy.errorMsg = errorMsg
            
        }


        const personValidations = [
            validatorHelper.validateFor('firstName').isRequired('First Name is required'),
            validatorHelper.validateFor('lastName', lastNameValidatorFn).isRequired('Last Name is required'),
            validatorHelper.validateFor('age').isRequired('Age is required').isNumber('Age should be number')
                .isNumberWithinRange('Age should be between 10 and 60', [10,60]),
            validatorHelper.validateFor('gender').isRequired('Gender is required'),
            validatorHelper.validateFor('email').isRequired('Email is required').isRegex('Enter valid email', 
            /^[a-zA-Z0-9.!#$%&’*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/),
            validatorHelper.validateFor('address.line1').isRequired('Street address is required'),
            validatorHelper.validateFor('address.city','address.line1.length > 0').isRequired('City name is required'),
            validatorHelper.validateFor('address.state','address.line1.length > 0').isRequired('State name is required'),
            validatorHelper.validateFor('address.zip','address.line1.length > 0').isRequired('Zip is required').isNumber('Zip must be a number')
                .customValidator('Invalid Zip Code, does not match with City and State', cityAndStateAsyncValidatorFn),
        ];

        return personValidations;
    }

}



// component
import { PersonValidationPolicy } from './simple.person.validation.policy';
import { NgxValidationRunnerService } from 'ngx-model-validator';

public PERSON_POLICY_NAME = 'simple-person-validation';
public PERSON_VALIDATION_FN = PersonValidationPolicy;

constructor(private valRunnerSvc: NgxValidationRunnerService){ }

validate() {
    this.valRunnerSvc.validate(this.PERSON_POLICY_NAME, this.person)
}

• Simple validation without error display on field, errors to be handled in component

<ngx-component-validator [model]="person" [policy]="PERSON_POLICY_NAME" [policyFnRef]="PERSON_VALIDATION_FN"></ngx-component-validator>

<input matInput placeholder="First Name" [(ngModel)]="person.firstName" />

// policy
validatorHelper.validateFor('firstName').isRequired('First Name is required'),

// component
this.valRunnerSvc.validate(this.PERSON_POLICY_NAME, this.person).subscribe(result=>{
      if(result && result.length > 0) {
         console.error('Validation error found');
      }
    });

• Simple validation with required * and error display on field

<ngx-component-validator [model]="person" [policy]="PERSON_POLICY_NAME" [policyFnRef]="PERSON_VALIDATION_FN"></ngx-component-validator>

<input matInput placeholder="First Name" ngxMatValidate ngxMatRequired [model]="person" validateProperty="firstName" [policy]="PERSON_POLICY_NAME" [(ngModel)]="person.firstName" />

// policy
validatorHelper.validateFor('firstName').isRequired('First Name is required'),

// component
this.valRunnerSvc.validate(this.PERSON_POLICY_NAME, this.person)

Development server

Run npm run start for a dev server. Navigate to http://localhost:4200/. The app will automatically reload if you change any of the source files.

Running unit tests

Run ng test to execute the unit tests via Karma.