Instruction: Explain the concept of CORS and how to implement CORS support in a Node.js application.
Context: This question tests the candidate's knowledge of web security principles, specifically CORS, and their ability to configure a Node.js application to safely interact with resources from different origins.
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In the context of Node.js, especially for roles like Backend Developer or Node.js Developer, understanding and effectively implementing CORS is crucial because Node.js often serves as the backend service providing APIs that web frontends consume. These frontends might be hosted on different domains, making CORS a necessary consideration to ensure smooth, secure communication between the frontend and the backend.
To implement CORS in a Node.js application, one of the most straightforward methods is by using middleware, such as the cors package for Express.js, a popular web server framework for Node.js. Here's a concise guide on how to do it:...