Node.js script.createCachedData() Method

In this article, we will discuss about script.createCachedData() in Node.js. Node.js is a great and flexible environment for running JavaScript on the server side. It consists of a number of intrinsic modules to improve the development process. One of the modules is the VM (virtual machine) module, which allows the execution of JavaScript code in a virtual environment that isolates the code from having effects on the global environment. In this particular module, the script.createCachedData() should also be mentioned as the tool that helps in controlling the speed at which the script regarding the cached compiled code is used to optimize it. In this broad analysis, we will discuss the function, use, advantages, and potential applications of the script.createCachedData() method.

What is the script.createCachedData() Method?

The script.createCachedData() method is located in the VM module and is used to create cached data for a specific script. This cached data is the script's internal compiled state and can be used more quickly in further operation for the second time. This means that there is no need to recompile or reprocess the script every time it is run to see its results. The use of createCachedData() can be helpful in several applications where commonly used scripts are run repeatedly.

Purpose of script.createCachedData()

In Node.js, the main purpose of the script.createCachedData() method improves the speed of a general script run by caching the compiled form of the script. When a JavaScript code is executed, it is first parsed and compiled with the help of a JavaScript engine. This script-compiling process can be time-consuming, especially when it comes to large or frequently run scripts. By caching the compiled state, script.createCachedData() also does not require the program to be recompiled, thus minimizing execution time and making the program more efficient.

Syntax:

It has the following syntax:

Parameters:

This method does not receive any parameters.

Return Value:

This operation returns the buffer type.

Examples:

Here are some examples to show how the script.createCachedData() method used in Node.js:

Example 1:

Output:

 <Buffer 62 05 de c0 82 a0 69 35 50 00 00 00 2f 12 c5 a8 d0 01 00 00 cc 40 10 d1 01 1c 53 01 2c 07 a8 60 00 00 00 00 1e 00 00 00 01 10 4c 60 00 00 00 00 02 00 ... 438 more bytes> 

Explanation:

• In this example, the vm module is imported so that it is possible to use an API for running a code in the context of a virtual machine can be used.
• After that, a new vMachine.Script instance is created, which is the object containing the compiled script. The script has a basic function called addition, which is defined as the function that takes two arguments as parameters and returns the sum of them.
• Next, the createCachedData() method is invoked on the script object. This method also creates and returns a cache of the compiled script, which can help with running the script faster the second time.
• The retrieved cached data is assigned to a cacheWith variable and then printed out to the console.
• The createCachedData() method is also advisable where a script is likely to be run for another time because it will save the time of compiling it again. If data caching occurs, the data can be stored and used again to run the script, which will eventually save time.

Example 2:

Output:

 <Buffer b4 03 de c0 24 53 84 3a 51 00 00 00 f8 be 20 82 06 00 00 00 80 02 00 00 b4 fe 09 b8 d5 c8 88 04 00 00 00 80 20 00 00 80 88 03 00 80 00 00 00 80 00 00 ... 646 more bytes> 

Explanation:

• This module is imported to work with an API that allows the execution of JavaScript code in the context of a virtual machine.
• A Script object is created, and this script object contains an already compiled script. The provided script includes a function called addition, which accepts two parameters and then it returns the sum of the two numbers.
• The runInThisContext() method is invoked on the scriptVal object. In this method, the script is run in the current context, which enables the addition function to be created and used.
• There is another method called createCachedData(), which is invoked on the scriptVal object. This method creates and returns a cached compiled script that can be reused to improve the script's runtime efficiency.

Conclusion:

In conclusion, the script.createCachedData() method in Node.js is an improvement in performance for the applications that contain scripts that are to be run over and over. It saves the execution time involved in recompiling a script each time it is run, which means a cached compiled state can be run many times with little to no compilation necessary. It is helpful when dealing with large scripts or frequently used scripts, thus making the program more efficient.