Mistakes That Node.js Developers Make and Should be Avoided

For the past few years, Node.js, accounting for its growth and popularity, has been a talking point for some time now. Well-establish companies like Walmart and PayPal have adapted it, making it one of the most recognized languages at present. However, as many other platforms, Node.js faces a lot of development problems that includes crucial mistakes committed by the developers themselves.

However, like any other platform, Node.js is vulnerable to developer problems and issues. Some of these mistakes degrade performance, while others make Node.js appear straight out unusable for whatever you are trying to achieve. In this article, we will take a look at ten common mistakes that developers new to Node.js often make, and how they can be avoided to become a Node.js pro.

1. Blocking the event loop

Being a single-threaded environment, no two parts of your application can run in parallel. Simply put, since Node.js runs on a single thread, anything which blocks the event loop, blocks everything. Here, concurrency is achieved by handling input-output operations asynchronously. For example, what allows Node.js to focus on some other part of the application is a request to the database engine, from Node.js to fetch some document. However, all it takes to block the event loop is a piece of CPU-bound code in a Node.js instance with many clients connected, making all the clients wait. There is no clear-cut solution to this problem, other than to address each case individually. The primary idea is to not do CPU intensive work within the front facing Node.js instances, the ones clients connect to concurrently.


2. Nested Callback or Callback Hell

If you properly analyze the common issues with Node.js, you would know that most of the problems are associated with callbacks and the callback hell or nested callback, whatever you may term it is one of the general mistakes.

In fact, this particular problem persists in most of the application development programs. The concern usually originates because the development of the application is a complex process. It also becomes difficult to maintain the codes.But you can sort out this issue by writing simple functions that are easy to read and providing them suitable links. For instance, codes such as Generators, Promises etc. will be helpful and you can keep the codes error free.The developers who expect that the call back will operate serially shouldn’t get under this misconception as everything is not carried out synchronously. Therefore, it is suggested that the addition must be done instantly after the call back to ensure everything goes smoothly.


3: Expecting Callbacks to Run Synchronously

Asynchronous programming with callbacks may not be something unique to JavaScript and Node.js, but they are responsible for its popularity. With other programming languages, we are accustomed to the predictable order of execution where two statements will execute one after another, unless there is a specific instruction to jump between statements. Even then, these are often limited to conditional statements, loop statements, and function invocations.

However, in JavaScript, with callbacks a particular function may not run well until the task it is waiting on is finished. The execution of the current function will run until the end without any stop:

function testTimeout() {
	setTimeout(function() {
	}, duration * 1000)

As you will notice, calling the “testTimeout” function will first print “Begin”, then print “Waiting..” followed by the the message “Done!” after about a second.

Anything that needs to happen after a callback has fired needs to be invoked from within it.


4. Lack of Profiling and Zero Monitoring

Often confused for testing, profiling is a completely different process. Profiling information helps with program optimization by studying various aspects related to the program like its space or function return time.In Node.js applications, profiling will help you understand things like delay in the event loop, system load, and CPU load or memory usage. If you to learn more about profiling and how it is done you can visit here


5. Developer is Unknown to Developing Tools

Often it is seen that in case the developers are inexperienced and fresher into the application development field, he remains unknown to the developing tools. It has already been indicated earlier that Node.js helps in complicated application building and if the developer is not familiar with the basic modules he may face problems.

The developer should know that if any change is done at the source, he has to restart and also he needs to refresh the browser when the static codes are getting modified and affecting the performance of the application. For restarting the server, you can use modules such as nodemon and for refreshing the nodemon and livereload is regarded appropriate. You can visit here to see all developing tools