React Cookie

Introduction to Cookies and React Cookie

Cookies are small pieces of data that are stored in a user's web browser and can be accessed by the server when the user visits a website. They are often used to store information about the user's preferences or browsing history, which can be used to personalize the user's experience on the website.

Cookies are typically stored as text files and are sent back and forth between the server and the browser as part of HTTP requests and responses. They can be set to expire after a certain period or to persist indefinitely, depending on the settings specified by the server.

React-Cookie is a small library that allows you to work with cookies in a React application. It provides a simple and easy-to-use API for working with cookies in a React application. It includes functions for setting, getting, and deleting cookies, as well as utility functions for checking the existence of cookies and getting all cookies.

React-cookie can be used on both the client and the server side. It also includes TypeScript definitions and comprehensive documentation, making it easy to use in TypeScript applications.

Features

Here are some key features of React Cookie:

• Easy to use:
  React-Cookie provides simple functions for setting, getting, and deleting cookies in a React application.
• Isomorphic:
  React-Cookie works on both the client and the server, making it easy to use in isomorphic applications.
• TypeScript support:
  React-Cookie includes TypeScript definitions, making it easy to use in TypeScript applications.
• Small size:
  React-Cookie is a small library, with a minified and gzipped size of less than 2KB.
• Comprehensive documentation:
  React-Cookie comes with extensive documentation, including examples and explanations of all of the available functions and options.
• Customisable:
  React-Cookie allows you to customize the behavior of the library through options such as the path, domain, and expiration of the cookie.
• Secure:
  React-Cookie includes security measures such as the ability to set the secure flag on cookies, which tells the browser to only send the cookie over a secure connection.
• Compatibility with other libraries:
  React-Cookie can be used with other libraries and frameworks, such as Redux and React Router, without any conflicts.
• Flexible API:
  React-Cookie provides a variety of functions for working with cookies, including functions for setting, getting, and deleting cookies, as well as utility functions for checking the existence of cookies and getting all cookies.

Installation and Setting Up the Cookie

To set up react-cookie in your React application, you will need to follow these steps:

• Install the react-cookie module using npm or yarn:

  or

• Import the useCookies hook from the react-cookie module into your React component:

• Use the useCookies hook to read and write cookies in your component. The useCookies hook returns an array containing the current cookies and a function for setting cookies. You can destructure this array into separate variables like this:

• To set a cookie, call the setCookie function and pass it the name of the cookie, the value you want to set, and any options you want to specify. For example:

• To read a cookie, access the value of the cookie from the cookies object. For example:

Thats it! Now you are ready to use react-cookie in your project.

Simple Example with React Hooks

We can also use the react-cookie library with React hooks. Let's see with the help of an example:

Explanation:

The useCookies hook returns an array containing the cookies object, a function to set a cookie, and a function to remove a cookie. The first argument to useCookies is an array of cookie names that you want to access in your component.

In the example above, we are using the cookies object to get the value of the my-cookie cookie, and we are using the setCookie and removeCookie functions to set and remove the my-cookie cookie.

Simple Example with Higher-Order Component

A higher-order component (HOC)in react is a function that takes a component as an argument and returns a new component. HOCs are a way to reuse code, abstract away logic, and provide additional functionality to a component.

Here is a simple example of using the react-cookie library with a higher-order component:

Explanation:

The withCookies HOC is a function that takes a component as an argument and returns a new one that has access to the cookies object and functions for setting and removing cookies. To use the withCookies HOC, you will need to import it from the react-cookie library and wrap your component with it.

In the example above, we are using the cookies object to get the value of the my-cookie cookie. The cookies object is passed to the component as a prop, and it has a get method that allows you to get the value of a cookie by name.

Server-Rendering Example

Server rendering is the process of rendering a React application on the server rather than in the browser. This allows the application to be served to the client as a fully-rendered HTML page, which can improve the performance and SEO of the application.

When using react-cookie with server rendering, you need to be careful to ensure that the cookies are available on the server and the client. This is because cookies are stored in the browser and are not accessible to the server by default.

One way to handle this is to use the universal-cookie library, which is a fork of react-cookie that is designed to work with server rendering. universal-cookie provides a ServerCookies class that allows you to access the cookies sent by the client in the server-side rendering process.

Here is an example of using the react-cookie library for server-side rendering with React and Express:

Explanation:

In this example, we are using the renderToString function from the react-dom/server module to render the MyApp component to a string. We are wrapping the component with the ServerCookiesProvider component from the react-cookie library, which provides the cookies object and functions for setting and removing cookies to the component.

The ServerCookiesProvider component takes the cookies object as a prop, which is provided by the universal-cookie middleware. The universal-cookie middleware is a middleware that provides a cookies object to the req object in Express, which allows you to access cookies in your server-side rendering code.

Some Tips While Using React Cookie

Here are some tips for using cookies effectively in a React application:

• Use cookies sparingly:
  Cookies can be a useful tool for storing small amounts of data, but they should not be relied upon to store large amounts of data or sensitive information. Consider using other storage options, such as local storage or a server-side database, for more significant data.
• Consider user privacy:
  Be mindful of user privacy when using cookies. If you are using cookies to track a user's browsing activity or store personal information, make sure to disclose this in your privacy policy and get the user's consent.
• Set expiration dates:
  Use the expires option when setting a cookie to specify how long the cookie should remain in the user's browser. This can help to ensure that the cookie is not retained indefinitely and reduces the risk of data breaches.
• Use secure cookies:
  If you are storing sensitive information in a cookie, make sure to set the secure option to true to ensure that the cookie is only transmitted over secure connections.
• Use the sameSite option to specify when a cookie should be sent:
  The sameSite option allows you to specify whether a cookie should be sent with requests made from a different domain. This can be useful for preventing cross-site request forgery (CSRF) attacks.
• Be aware of browser cookie limits:
  Different web browsers have different limits on the number and size of cookies that can be stored. Be mindful of these limits to ensure that your application can store the necessary data without running into issues.
• Test your cookie functionality:
  Make sure to test your cookie functionality thoroughly to ensure that cookies are being set, read, and deleted as expected.