Angular is an open-source web application framework maintained by Google and the community that can be used to build single-page applications (SPAs). It aims to solve the challenge of creating rich, interactive applications on both desktop and mobile browsers without sacrificing performance. 

In this article, we will explore some Angular development services based  security best practices you should follow while building modern, Single Page Applications (SPA).

What is Angular? 

Angular is an open-source web application framework built on TypeScript, developed by Google, and maintained by a community of individual contributors and corporate sponsors. Angular uses HTML as a templating language to define the structure of an application's user interface (UI) components. With its declarative templates and dependency injection, it offers a single view for the data that changes over time.

Should know - Angular Security and Best Practices

Secure Your Routes

If you’re using ngRoute, you need to make sure that every route has a valid guard. By default, every route will redirect a user to a login page if they try to access it without logging in first. 

You can customize which routes require authentication by adding properties to your angular-cli.json file. There are three different levels of security: Level One is the least secure because all routes are accessible to anyone who visits the site; Level Two requires users to log in before accessing any part of the site; Level Three is the most secure because only logged-in administrators have access.

Use HTTPS

The first step to make sure your app is secure is to always use HTTPS. This ensures that the information you are sending between the client browser and server can't be intercepted by a third party. If you don't use HTTPS, the data will be transmitted in plain text which means anyone on the network can see it. 

You should also always include the 's' when using HTTP (HTTPS). Protect Your Data: It's important to protect your data so it doesn't get hacked. It's crucial to not store any sensitive information on an individual's device or computer because they could lose their device or someone could steal their laptop with all of their work saved there. Encrypting sensitive information such as passwords and credit card numbers is an important part of protecting this data from being stolen or hacked.

Implement CORS

CORS stands for Cross-Origin Resource Sharing, which is a mechanism that allows web pages from one domain to access data from another domain. CORS is often applied to AJAX requests, where the browser sends data to the server without a page reload. CORS can be implemented with a few lines of JavaScript and doesn't require any changes on the server side. 

To implement it in your app's frontend, you just need to add code like below:
A simple way to implement CORS is by using the $http service. You can simply update your headers in each request as follows

Sanitize user input

Sanitizing user input is one of the best ways to keep your site from getting hacked. When you get data from a website, make sure to filter out any potentially malicious strings or characters that could harm your system. 

This is done by using regular expressions to validate all input. Regular expressions are patterns that can be used to match text (find matches). Regular expressions are defined as syntactic scripts for pattern matching with various syntax languages such as Perl, JavaScript and Python. These languages allow an expression to be compiled against some text in order to determine whether there is a match.

Validate user input

User input can come from many sources, including user input, the URL or form parameters, or server response. All of these types of input must be validated to ensure that the input is safe before it is used in your application. 

By not validating data from input sources, you put your application at risk for malicious attacks like Cross-site Scripting (XSS), SQL injection, clickjacking and more. To prevent such attacks, Angular provides a set of common functions designed to validate different kinds of input. 

Use cookies securely

Cookies are small pieces of data that are stored in your web browser by a web server. They can be used to store information such as the user's login credentials, shopping cart items or visited pages on a site. 

Cookies can be accessed by the server every time the user makes a request to view a page from that server. This means that if your computer accesses two different pages with cookies set by the same domain, then both servers will be able to see these. 

One common way for this problem to occur is when someone leaves their computer logged into an account on a public wifi network. For this reason, it is best practice for developers to not use sessions or cookies for sensitive data (such as passwords) and instead rely on HTTP Basic Authentication.

Protect against XSS attacks

One of the most common security vulnerabilities is cross-site scripting (XSS) attacks. These occur when an attacker injects malicious code into a user's browser by way of a script, video, image, or other form of HTML request. The malicious code then executes on the victim's browser as if it were from the server itself. This enables attackers to steal data or take over accounts. One of the best ways to protect against XSS attacks is to encode all your output with JavaScript's encodeURIComponent() function. 

There are more complicated encoding techniques available, but this is one that any developer can easily implement with little fuss. Another good technique for protecting against XSS attacks is using JSON Web Tokens instead of cookies for authentication.

Conclusion

Angular is an open-source framework for building mobile and desktop web applications. It has a robust collection of features that make it an ideal choice for developers working on any type of application. One downside, though, is that it's less popular than other frameworks like ReactJS or VueJS. This means that not as many people are looking for security vulnerabilities in the code.