Introduction:
Implement reCAPTCHA in Angular for free. reCAPTCHA is a free service from Google that helps protect websites from spam and abuse. It uses advanced risk analysis techniques to tell humans and bots apart, and it can be used to prevent automated bots from performing malicious actions on your website. Implementing reCAPTCHA in an Angular application can help protect your website from spam and abuse, while still providing a seamless user experience.
In this article, we will guide you through the step-by-step process of how to Implement reCAPTCHA in an Angular application. We will cover everything from creating a reCAPTCHA account and getting a site key and a secret key, to installing the ngx-captcha package and validating the reCAPTCHA token on your server. By the end of this article, you will have a clear understanding of how to integrate reCAPTCHA into your Angular application and help protect your website from unwanted spam and abuse.
Implement reCAPTCHA in Angular applications involves several steps:
First, you need to create a reCAPTCHA account and register your site to get a site key and a secret key. You can do this by visiting the reCAPTCHA website and following the instructions there.
Here are the steps to create a reCAPTCHA account and register your site:
- Go to the reCAPTCHA website at https://www.google.com/recaptcha/about/.
- Click on the “Admin Console” button in the top right corner of the page.
- Sign in to your Google account if you haven’t already.
- On the reCAPTCHA Admin Console page, click on the “+ Add” button in the top right corner of the page.
- Fill in the necessary fields, including the label for your reCAPTCHA, the type of reCAPTCHA you want to use (v2 or v3), and the domains where you will be using the reCAPTCHA.
- Accept the terms of service and click on the “Submit” button.
- On the next page, you will see your “Site Key” and “Secret Key”. These are important keys that you will need to implement reCAPTCHA on your site.
- Copy the Site Key and Secret Key and save them in a safe place.
- Follow the documentation provided by Google to add reCAPTCHA to your site.
Next, install the ngx-captcha package using npm. This package provides a wrapper around the reCAPTCHA API that you can use in your Angular application. To install this package, run the following command in your terminal:
npm install ngx-captcha --save
Once the package is installed, you can import the ReCaptchaV3Module module into your Angular application. This module provides the ngx-captcha the component that you can use to display the reCAPTCHA widget. To import this module, add the following line to your app module:
Import NgxCaptchaModule to your module (i.e. AppModule)
@NgModule({
imports: [
NgxCaptchaModule ,
// other imports
],
// other declarations
})
export class AppModule { }
In your component where you want to use the reCAPTCHA, you need to inject the ReCaptchaV3Service service and call its execute method. This method returns a promise that resolves with a token that you can use to validate the reCAPTCHA.
Here’s an example to Implement reCAPTCHA in Angular:
import { Component } from '@angular/core';
import { ReCaptchaV3Service } from 'ngx-captcha';
@Component({
selector: 'app-my-component',
template: `
<ngx-captcha [siteKey]="siteKey" (resolved)="onResolved($event)"></ngx-captcha>
`,
})
export class MyComponent {
siteKey = 'your_site_key_here';
constructor(private recaptchaV3Service: ReCaptchaV3Service) {}
onResolved(token: string) {
console.log('reCAPTCHA resolved with token:', token);
// Use the token to validate the reCAPTCHA on your server
}
async executeReCaptcha() {
const token = await this.recaptchaV3Service.execute(this.siteKey, 'myAction');
console.log('reCAPTCHA token:', token);
// Use the token to validate the reCAPTCHA on your server
}
}
In this example, we’re using the ngx-captcha component to display the reCAPTCHA widget, and we’re listening to the resolved event to get the token when the user solves the reCAPTCHA. Alternatively, we can call the execute method of the ReCaptchaV3Service service to get the token programmatically.
Finally, you need to validate the reCAPTCHA token on your server. You can do this by sending a POST request to the reCAPTCHA API with the token, along with your site key and secret key. The reCAPTCHA API will return a response that indicates whether the reCAPTCHA was valid or not. You can then use this response to allow or deny access to your application.
How to validate the reCAPTCHA token on your server?
To validate the reCAPTCHA token on your server, you need to send a POST request to the reCAPTCHA API with the following parameters:
secret: Your reCAPTCHA secret key.response: The reCAPTCHA token that you received from the client.remoteip: The IP address of the client that solved the reCAPTCHA. This is an optional parameter.
Here’s an example of how you can implement the server-side validation in Node.js using the axios library:
const axios = require('axios');
const validateRecaptcha = async (recaptchaToken, remoteip) => {
const secretKey = 'your_secret_key_here';
const url = 'https://www.google.com/recaptcha/api/siteverify';
try {
const response = await axios.post(url, {
secret: secretKey,
response: recaptchaToken,
remoteip: remoteip,
});
return response.data.success;
} catch (error) {
console.error('Error validating reCAPTCHA:', error);
return false;
}
};
In this example, the validateRecaptcha the function takes the reCAPTCHA token and the remote IP address as parameters, and sends a POST request to the reCAPTCHA API to validate the token. The function returns a Boolean value indicating whether the reCAPTCHA was valid or not.
You can then call this function in your server-side code to validate the reCAPTCHA token before allowing the user to perform any sensitive action on your application. For example:
app.post('/login', async (req, res) => {
const recaptchaToken = req.body.recaptchaToken;
const remoteip = req.connection.remoteAddress;
const isRecaptchaValid = await validateRecaptcha(recaptchaToken, remoteip);
if (isRecaptchaValid) {
// Allow the user to log in
// ...
} else {
res.status(401).send('Invalid reCAPTCHA token');
}
});
In this example, we’re validating the reCAPTCHA token in a server endpoint that handles a login request. We’re extracting the token and the remote IP address from the request, and calling the validateRecaptcha function to validate the token. If the token is valid, we allow the user to log in. If not, we return a 401 Unauthorized status code.
How to validate the reCAPTCHA token on your web server? E.g. WEB API using DOTNET CORE
To validate a reCAPTCHA token on your server in a .NET Core web API, you can follow these steps:
- Get the reCAPTCHA response token from the client side. This token is generated by the reCAPTCHA widget on the client side and is sent to the server for validation. Use the token from the above step.
- Use the HttpClient class to send a POST request to the Google reCAPTCHA verification API with the token as a parameter.
- Parse the response returned from the Google reCAPTCHA verification API to determine whether the token is valid or not.
Here’s an example code snippet that demonstrates how to validate a reCAPTCHA token in a .NET Core web API:
using System;
using System.Net.Http;
using System.Threading.Tasks;
public class RecaptchaService
{
private readonly HttpClient _httpClient;
private readonly string _recaptchaSecretKey;
public RecaptchaService(HttpClient httpClient, string recaptchaSecretKey)
{
_httpClient = httpClient;
_recaptchaSecretKey = recaptchaSecretKey;
}
public async Task<bool> IsTokenValid(string token)
{
var requestContent = new FormUrlEncodedContent(new[]
{
new KeyValuePair<string, string>("secret", _recaptchaSecretKey),
new KeyValuePair<string, string>("response", token)
});
var response = await _httpClient.PostAsync("https://www.google.com/recaptcha/api/siteverify", requestContent);
response.EnsureSuccessStatusCode();
var responseContent = await response.Content.ReadAsStringAsync();
dynamic responseObject = JsonConvert.DeserializeObject(responseContent);
return responseObject.success == "true";
}
}
In the above example, we are using the HttpClient class to send a POST request to the Google reCAPTCHA verification API with the reCAPTCHA token and secret key as parameters. We then parse the response and return a boolean value indicating whether the token is valid or not.
Note that you will need to obtain a reCAPTCHA secret key from the Google reCAPTCHA website in order to use this service.
Application Source Code @ LearnSmartCoding GitHub
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Conclusion:
Implementing reCAPTCHA in the Angular application is a simple yet effective way to protect your website from spam and abuse. With the help of the reCAPTCHA API and the ngx-captcha package, you can easily add a layer of security to your website and prevent malicious bots from performing unwanted actions. By following the step-by-step guide provided in this article, you can easily integrate reCAPTCHA into your Angular application and ensure that your users have a safe and secure browsing experience. So, don’t wait any longer and start implementing reCAPTCHA in your Angular application today!
