Feb 14, 2018

Node.js: Traversing A Directory Recursively with Limited Depth

In this post, we will implement to get all files recursively in a directory using Node.js. Also, will restrict it to traverse directory with limited recursively depth.

Before we get started, consider the following directory structure(For simplicity, the name is according to their depth level i.e. folder 1, sub folder 1.1, sub sub folder 1.1.1...etc):


1 > 1.1 > 1.1.1> 1.1.1.1 > 1.1.1.1.1
2 > 2.1 > 2.1.1
  > 2.2

Each directory has txt file with same directory name(means 1.1 will have 1.1.txt file).

nodejs-dfs

Let's start with a simple method to get all files:


function getAllFiles(dirPath){
      fs.readdirSync(dirPath).forEach(function(file) {
      let filepath = path.join(dirPath , file);
      let stat= fs.statSync(filepath);
      if (stat.isDirectory()) {            
        getAllFiles(filepath);
      } else {
            console.info(filepath+ '\n');                      
      }    
  });  
}
getAllFiles('./temp');

Output:



temp/1/1.1/1.1.1/1.1.1.1/1.1.1.1.1/1.1.1.1.1.txt

temp/1/1.1/1.1.1/1.1.1.1/1.1.1.1.txt

temp/1/1.1/1.1.1/1.1.1.txt

temp/1/1.1/1.1.txt

temp/1/1.txt

temp/2/2.1/2.1.1/2.1.1.txt

temp/2/2.1/2.1.txt

temp/2/2.2/2.2.txt

temp/2/2.txt

To limit recursively depth, let's add two more parameters:


function getFiles(dirPath,  currentLevel, maxLevel){
  if (currentLevel > maxLevel){
    return;
  }
  else{
      fs.readdirSync(dirPath).forEach(function(file) {
      let filepath = path.join(dirPath , file);
      let stat= fs.statSync(filepath);
      if (stat.isDirectory()) {            
        getFiles(filepath, currentLevel+1, maxLevel);
      } else {
            console.info(filepath+ '\n');                      
        }    
  });
  }
}

maxLevel defines the maximum depth to traverse. Let's get files with max 2 levels.


getFiles('./temp',0,2);

Output:


temp/1/1.1/1.1.txt

temp/1/1.txt

temp/2/2.1/2.1.txt

temp/2/2.2/2.2.txt

temp/2/2.txt

To get files from sub-folders only, set maxLevel = 1


getFiles('./temp',0,1);

Output:


temp/1/1.txt

temp/2/2.txt

Conclusion:

In this post, we saw how to get all files from a given directory using recursion and specified max depth limit. Hope, It helps.

Enjoy Node.js!!

Node.js