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Node js Interview Questions From Junior to Senior level by Alex Vasilyev Geek Culture

Transform streams are the same as duplex streams, but they can modify or transform the data while reading or writing it. Pass-through streams are a more trivial implementation of transform streams. Regular functions are quite ordinary, but arrow functions have been introduced recently by ES6 to enable writing concise JS functions. Regular functions are constructible as they can be created with a function declaration or expression.

• Process.nextTick() defers the execution of a function until the next iteration of event loop begins.
• In general, an understanding of a team workflow is expected from seniors.
• The main disadvantage of this approach is thread overhead.
• This Node module enables you to use trace events, tracking information generated by V8, user-space code, and Node.js core on the central system.

It enables fast two-way messaging between client and server and deploys real-time applications quickly and efficiently. It works effectively with Node.js, ensuring that real-time communication and data flow are hassle-free. Now you can quickly implement live chat applications with Node.js WebSockets. Asynchrony sometimes causes callback nightmares and degrades the app’s performance. It is vital to avoid a situation where callbacks are nested several levels deep within other callbacks, making the JavaScript code challenging to maintain.

Middle: Node.js Technical Interview Questions

Events are one of the core features of Node JS. They symbolize some action taken or done on a web page. They are controlled by an event handler that writes the code necessary to execute these events. Of all the basic questions about Node.JS, this is certainly the main one. Naturally, this is also often the first or one of the first questions that you can ask in an interview. The first function I was asked to write simply had to change a large amount of data contained in a string into a JS object.

If you have any kind of doubts regarding these questions, feel free to post them in the comments below, and our team will get back to you at the earliest. There is more harmony and efficiency, and junior node js developer we have higher-quality components than before. This also allows us to work better together across the company. A smart interface helps you track your progress and focus on the topics you need.

Node.js is a popular server-side platform using which one can build everything, starting from a simple command-line tool to a complex enterprise-level app. It’s a sound reason why there is a demand for an experienced Node.js Developer. By writing a job description, you are creating a profile of your ideal candidate, including his knowledge, hard and soft skills, experience and previous projects .

Get the inside track on what to expect in your next tech interview. We offer you a collection of high quality technical interview questions to help you prepare for your next coding interview. In addition to coding abilities, junior developers must have strong problem-solving skills to debug and solve development issues quickly and efficiently. Node.js developer job interview questions and the best ways to answer them. It will help you comprehend the essential concepts of Node.js. When you start the block function, all other parts of the code are not applied until a specific, assigned I / O event is completed.

Intermediate Node JS Developer Interview Questions For 2 Year Experience

This blog will discuss the most frequently asked questions in Node.js developer job interviews. While hiring Node.js developers for your business, you can ask the following questions to select assets for your company. Node.JS developer job https://xcritical.com/ interview questions are significant is that they allow you to assess your degree of Node.JS understanding. After considering the candidate’s degree of qualification, you can pick what difficult questions to pose to the developers later.

They are most often used in the test, because they can provide the answers necessary to solve problems that may arise in the modules. Even experienced Node JS specialists sometimes cannot answer this question smoothly. When a developer is completely immersed in the work on Node.JS, they do not always think about what it is.

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It is at the core of asynchronous event-driven architecture of NODE. An event emitter is a pattern that listens to a named event, fires a node.js callback, then emits that event with a value. Node.js is a single-threaded process that does not expose thread management methods and child threads to the developer. However, some tools enable threading support in a Node.js application, like the ChildProcess module.

The role of junior tech employees remains one of the most sought-after hires in the tech world, although they require more technical training than experienced employees. When interviewing a junior developer, asking technical and non-technical questions is essential. Why there’s a need to ask these Node.js interview questions for experienced developers? Before submitting code to the Quality Assurance team, the developer should run automated code tests — it greatly optimizes the software development process. It would be best to ensure the candidate knows how to do it.

How to Nail your next Technical Interview

At the first stage of your search for a developer, look at the portfolio of candidates. A candidate who does not show growth and development does not deserve attention. It is essential to prepare in advance Node.js interview coding questions and answers for different levels. We understand that interview questions on Node.js of specialists of different levels differ in complexity.

Because of EventLoop mechanism callbacks in setTimeout and setInterval are always called after defined time with some delay. This method doesn’t generate a new V8 instance, and only a single copy of the node module is active on the processor. The control flow function is a piece of code that runs in between several asynchronous function calls.

Why Node.js devs tend to lean towards the Module Requiring vs Dependency Injection?

Why there’s a need to ask these full-stack Node JS developer interview questions? API is something both front-end and back-end developers have to work with. They must know the basics of network data transfer to avoid critical security errors. It allows other code to be run in the meantime and prevents any blocking. Being an asynchronous platform, Node.js heavily relies on callback. AnyforSoft share their experience with Node.js interview questions.

Why there’s a need to ask these Node.JS interview questions? Node.js is the technology that enabled the development of the back-end with JavaScript. You can’t work with a JavaScript runtime environment without knowing JavaScript itself. This section will provide you with the Advanced Node.js interview questions which will primarily help experienced professionals. This is accomplished through the use of nextTick() and setImmediate(). We have compiled a comprehensive list of common Node.js interview questions that come up often in interviews and the best ways to answer these questions.

Also, they should avoid user-supplied input containing malicious SQL from influencing the query logic. Process.nextTick() defers the execution of a function until the next iteration of event loop begins. This technique enables you to convert data between incompatible type systems with the help of object-oriented programming languages. We’ll explain why each block is important for the developer to know.

Relation databases are best used when your app has to support dynamic queries. Meanwhile, non-relational databases are the best choice if you prioritize easy scalability. In JavaScript, the keyword “this” refers to the object it belongs to. It refers to a global object if located alone or in a function, to a local object if located in a method, or to an event if located in an event.

Junior Developer Roles and Responsibilities

Node.JS developer job interview questions and answers that you can ask junior engineers. These questions can be requested at the start of the interview after the candidates introduce themselves. Due to its asynchronous and event-driven model, we can use Node.js to create server-side data-intensive applications.

If you want to hire a Node JS specialist, you will need to know what questions you can ask. If you study the questions and answers presented in this guide, you should get a pretty good idea of ​​what you can expect from the candidate. Although this is simply a question from the “what is …? The candidate may also mention that callback hell can actually be resolved. It works so that this process simply breaks down callbacks into separate functions that are independent of each other. Stubs are specific functions that mimic the behavior of certain modules.

It is better to start maintenance with the code review because that is where the most critical problems can be hidden. The use of additional tools for auditing is welcome, but it is worth defining the criteria and configuration of microservices. This will help improve code quality and product efficiency. You can also update the technical stack or make appropriate updates to the options. At a time when the whole world is striving for mobility and accessibility, developers have to prioritize mobile-friendly designs, especially when it comes to web pages.

How does Node.js overcome the problem of I/O operations blocking?

They are carried out one by one after receiving the response. Here we offer you Node.js interview questions for freshers – 1-year experienced developers. These questions will help you understand their soft skills, understand the desire to learn, and improve themselves as specialists.

What do you mean by Asynchronous API?

If you are preparing for a career change and have an upcoming job interview, it’s always a good idea to prepare and brush up on your interview skills beforehand. Node.js was created explicitly as an experiment in async processing. A Node.js class has objects that are capable of emitting events.

How to Insert an Image in HTML Easily in 6 Steps

We are personally big fans of Affinity Photo, as it is cheap and gives you almost identical features to that of Adobe Photoshop. One problem with formatting them is that modifications often reduce their quality . That’s not a bad thing as long as you don’t make them ugly. When customizing a website, you might encounter some limitations when adding images to a page.

Now restart the chrome and the site can display images. Check these 8 ways to fix images not showing on website. If the above methods don’t work, you can download 4DDiG Photo Repair to repair the corrupted image which can fix these problems too. She has worked with local online businesses, supplying print and web content, and pursues an active interest in the computer, technology and gaming industries.

GIFs afford transparencies and animation but their cost comes at the file size. Having a 1500px wide gif wouldn’t be the best option for your site’s loading page speed. It’s best to keep the file sizes at less than 1MB especially if you intend to use them as a background image for your hero section. You will want to have a high res video in your hero section as a smaller gif may be really pixelated if it’s forced to upscale in your browser. Vertical/sky scrapper banners are also popular at 160px by 600px.

Share your photos!

Look up the image’s name in another source or search engine, such as Google. Search for the name of the picture and see if it is showing on Google or not. The following are some of the solutions to “Can’t see images on browsers”. To do that, open the run prompt and type ‘%localappdata%’.

JPEGs are generally going to be much smaller in file size than PNGs, for example, so it’s important to choose the right file type for the job. Outside of the image editing software, there are also several powerful free image optimization tools that you can use to optimize images for the web . For those who don’t know the difference between each file type, the PNG image format is uncompressed which means it is a higher-quality image.

GIF is the only universally available image format that offers animation capability. Though in some cases you can get by with CSS animations (sprite-based PNG/JPG), or serving APNG to Chrome/Firefox and GIF to all else. Similarly most “GIF” sharing sites will attempt to use HTML5 video with a GIF fallback for browsers that don’t support HTML5 video. GIPHY, like most “GIF” https://wizardsdev.com/ sharing sites, actually serves more HTML5 videos than GIFs as they can be higher quality and smaller filesize, with an optional GIF fallback. If you upload a video clip to these sites, they will typically use an automated process to produce a gigantic fallback GIF . These aren’t great sites for GIF viewing, but they are very efficient sites for GIF-esque video.

Beware of decorative images

For online shopping, high res images are essential so the visitor can ‘see’ the product in as much detail as possible. Following is the output for Should you prefer WebP image format to PNG the image as a link, clicking on the image will navigate us to google home page. Following is the syntax to add image as a link on the web page.

Content management systems and website themes usually provide fixed options for inserting images, which might not suit everyone’s needs. Check the code once more before clicking the Update File button to save the changes. Then, reload the website to see if the changes are successful. Scroll through the Theme Files section and click on the HTML file you want to add an image to. For example, if you want to add a logo to the header, click the header.php file. Make sure your website can handle everything – from high traffic to fast loading times, and more.

Hero Image Sizes for Mobile

Lossy and lossless compression are two methods commonly used. This article is an overview of image sizes for website owners, with guidelines for determining the best image dimensions. While the dimensions of the images are important, the file size of the images is also a big concern. Using the lazy loading script will only load crucial images as a priority for users who have image-heavy websites. Resolution120 MP limitTo find your image resolution, use this calculator or multiply the dimensions and divide by 1 million.

You must create an account or sign in if you want to edit this album later on. Websites are unique according to the style chosen by the creator. Sites that use WordPress, Shopify, Wix, Squarespace, and other CMS, require images of recommended sizes. There is more to just ensuring that the dimensions of an image are accurate when considering SEO. Below are some of the other important aspects to consider for image optimization.

The alt Attribute

If you have such a problem, you can solve it by using the solutions listed above. Moreover, if you find out that your images are corrupted, you can repair those images via 4DDiG Photo Repair. After the repair, you can choose photos to preview and then click Export to save them to a safe location. Tap Click to add photos to import damaged or corrupted photos and then tap Repair to start repairing them.

The next time you open it, you’ll see the webpage with your newly added image. While a browser can render an image without the alt attribute, it’s considered a best practice to include this attribute. That’s because this attribute contains image alt text. In the next article, we’ll move it up a gear, looking at how to use HTML to embed video and audio content in web pages. Earlier we said to never hotlink to images on other servers, but this is just for learning purposes, so we’ll let you off this one time. If your main heading needs a drop shadow, for example, use CSS for that rather than putting the text into an image.

Keeping the image file size to the minimum aids in increasing the loading time of the website. Today, 90% of website traffic is generated from mobile devices. On mobile websites, the hero images display well at a size of 800px by 1200px. However, content management systems automatically scale images to suit a mobile device browser.

• Open the public_html directory, double-click the wp-admin – images folder.
• Now open incognito in your Chrome and open any website and see if the images are showing or not.
• Resize images in ImagifyImagify also compresses images on their third-party servers, not yours, which is very important when it comes to performance.
• These large, high-res photos are beautiful but it is largely unnecessary to keep them this size when using them on a webpage.
• Alt text also tells search engines what the image is about, making it more likely your site will show up in image searches.

Videos that play audio automatically are ranked as one of the most annoying experiences a website can offer. Plus, adding audio will increase your file size so we suggest you just remove it if it’s not needed or have it muted by default when the page loads. Good alt tags help all the hard working web crawlers to figure out what your images are about while they further index your site.

Plan campaigns, create content, and seamlessly collaborate across teams. Or, create an account for $20 off your first month of Application Hosting and Database Hosting. You mentioned, “Use web fonts instead of placing text within images – they look better when scaled and take less space”.

Look into the @font-face CSS3 tool, which allows you to use custom fonts on a website without the use of an image. Be careful, though; RGBa values do not work in Internet Explorer 8 and earlier. In IE, your website will have no background color at all. What you essentially have is the functional equivalent of an inline frame, without the inconvenience of using an inline frame. If you want to center the image on the page, set your entire website to be centered by modifying the alignment in the “body” section of the stylesheet, e.g.

Why is image size important for websites?

For example, an image that’s 1500px x 1650px is 2.47 MP.Color modeRGB CMYK color mode is only for printed materials and won’t appear correctly in most browsers. Keep your page size under 5 MB to ensure your site loads quickly. If you notice your site loads slowly, visit Reducing your page size for faster loading. The smaller of the two image files is then served up using Kinsta’s lightning-fast CDN to boost speed even further. Customers can even pick between lossless and lossy compression depending on their needs.