Since Node JS comes with a single-threaded environment, no two parts of a Node JS application can run parallelly.<\/p>\n\n\n\n
So, If the event loop is blocked, it causes blocking everything.<\/p>\n\n\n\n
The solution is to use open-source modules like StrongOps.<\/p>\n\n\n\n
StrongOps can identify and fix any delays in the event loop and prevent from blocking the event loop.<\/p>\n\n\n\n
Trying to Execute Multiple Callbacks<\/strong><\/h3>\n\n\n\nCallbacks is used to allow asynchronous elements to communicate with each other.<\/p>\n\n\n\n
However, executing the same callbacks or multiple callbacks all at once can cause interface freeze.<\/p>\n\n\n\n
Therefore, it\u2019s important to ensure you\u2019re not continuously pressing for callbacks multiple times.<\/p>\n\n\n\n
There are two ways to avoid that.<\/p>\n\n\n\n
First, you can wrap the callback so you\u2019ll be notified each time a callback is executed twice.<\/p>\n\n\n\n
The second solution is to add a return before the callback to prevent invoking the same callback more than once.<\/p>\n\n\n\n
Callback Hell<\/strong><\/h3>\n\n\n\nCallback Hell means multiple nested callbacks that make nesting callbacks difficult and impossible to read & debug the written code.<\/p>\n\n\n\n
There are many ways to keep the code easy-to-read and debug such as using promises.<\/p>\n\n\n\n
A promise is basically a value returned to confirm the processing done by an asynchronous function. In simple terms, promises can be nested to make complex code look clear and easier to maintain.<\/p>\n\n\n\n
Another way is to use the async module that provides a straight forward, powerful functions to work with asynchronous JavaScript.<\/p>\n\n\n\n
Using Console.log for Debugging<\/strong><\/h3>\n\n\n\nConsole.log in the NodeJS is to print almost anything to the console. When Console.log is used to debug, it restarts the server and slows down the performance of the application.<\/p>\n\n\n\n
We can\u2019t use console.log every time. So instead of console.log, we can use the Debug Library.<\/p>\n\n\n\n
<\/p>\n\n\n\n
This is all for now.<\/p>\n\n\n\n
Hope you enjoy that.<\/p>\n\n\n\n
By Asahi<\/p>\n
\n <\/g:plusone><\/div>\n
Callback Hell means multiple nested callbacks that make nesting callbacks difficult and impossible to read & debug the written code.<\/p>\n\n\n\n
There are many ways to keep the code easy-to-read and debug such as using promises.<\/p>\n\n\n\n
A promise is basically a value returned to confirm the processing done by an asynchronous function. In simple terms, promises can be nested to make complex code look clear and easier to maintain.<\/p>\n\n\n\n
Another way is to use the async module that provides a straight forward, powerful functions to work with asynchronous JavaScript.<\/p>\n\n\n\n
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