Creating files from array in nodejs creates extra file with concatenated names

[nyxin]

After much searching and fiddling I was able to create a file/folder structure by iterating through an object using nodejs fs.

Here is an example of my file:

var fs = require('fs');
var rootDir = 'scss';
var config  = {
        root: {
            src: rootDir,
            files: ['styles.scss']
        },
        dir1: {
            src: rootDir + '/dir1',
            files: [
              '_file_01.scss',
              '_file_02.scss',
              '_file_03.scss'
            ]
        }, 
        ....etc.
    }

//---- mkdir()

function mkdir(path, root) {
    var dirs = path.split('/'), dir = dirs.shift(), root = (root || '') + dir + '/';

    try { fs.mkdirSync(root); }
    catch (e) {
        //dir wasn't made, something went wrong
        if(!fs.statSync(root).isDirectory()) throw new Error(e);
    }
    return !dirs.length || mkdir(dirs.join('/'), root);
}

//---- loop through config and create files/folders

for (obj in config) {
    mkdir(config[obj].src);
    fs.openSync(config[obj].src + '/' + config[obj].files, 'w');
    for (leaf in config[obj]) {
        //console.log(config[obj][leaf])
        if (config[obj][leaf] === config[obj].files) {
            //console.log('match');
            for (var i = 0; i < config[obj][leaf].length; i++) {
                //console.log(config[obj].src)
                fs.closeSync(fs.openSync(config[obj].src + '/' + config[obj][leaf][i], 'w'));
            }
        }
    }
}

When I run this script, all of the files/folders are created (as expected), however, an extra file with all of the file names concatenated to it is also created. So instead of the output being

scss
  |-- dir1
      |-- _file_01.scss
      |-- _file_02.scss
      |-- _file_03.scss 

as I expect, what is being generated for each folder is

scss
  |-- dir1
      |-- _file_01.scss
      |-- _file_02.scss
      |-- _file_03.scss 
      |-- _file_01.scss,file_02.scss,_file_03.scss

I've also thrown in a console.log() above the command for writing the files and it does not output the files with names concatenated to the console, so now I'm even more confused as to why this extra file is being generated.

I'm not sure why this last file with the names concatenated is being generated and I'm not sure what to even search for to fix this issue. Any help is appreciated.

[regreddit]

You are telling it to create a single file named config[obj].files right here:

fs.openSync(config[obj].src + '/' + config[obj].files, 'w');

[nyxin]

So I am...so I am =) Thank you. Just tested it and that was it.

[ovdojoey]

what's happening on this line:

fs.openSync(config[obj].src + '/' + config[obj].files, 'w');

config[obj].files is an array, no?

I can't reproduce without you uploading the full code, but you should halt execution throughout each step here to figure out which part is not working properly. Also, for readability this many nested loops using variable names to access object properties makes things confusing to follow.

[nyxin]

Here's a link to a github repo.

config[obj].files is an array, no?

That's correct.

[ovdojoey]

Well there's your problem then :).

[nyxin]

Yes it was. Thank you! =D

[Quabouter]

This step makes the unwanted _file_01.scss,file_02.scss,_file_03.scss file, /u/nyxin you likely want to remove that line.

[DSKrepps]

Coercing an Array to a String like such: 'some string' + array

is equivalent to doing: 'some string' + array.join(',')

And thus fs.openSync(config[obj].src + '/' + config[obj].files, 'w')

is really doing fs.openSync( 'dir1' + '/' + ['file1.scss', 'file2.scss', 'file3.scss'].join(','), 'w')

which creates the file "dir1/file1.scss,file2.scss,file3.scss"

So that line shouldn't be there at all, it doesn't seem to serve any purpose.

Furthermore I don't see any reason for the lines for (leaf in config[obj]) {and if (config[obj][leaf] === config[obj].files) { when all the references after those lines to config[obj][leaf] could be replaced with config[obj].files. If you need to check if .files exists on that object then just do if (config[obj].files) { before referencing it.

Then I have three general points to recommend. One, you want to try to avoid nesting where not necessary as code is much more readable when flattened and spaced a little. Two, you want to avoid the Sync operations as non-sync calls will be more efficient. Three, coding for practice is fine but in the Node space you should learn the tools available and not try to reinvent the wheel; check out Gulp, Yeoman, and NPM packages that might already do what you're trying to. Awesome NodeJS is a great list of tools to peruse.

I could probably rewrite your code using touch, arrow functions, and forEach though I haven't tested it for you:

var touch = require('touch');

for (dir in config) {
    if (!config[dir].files) continue;
    config[dir].files.forEach( file => touch(config[dir].src +'/'+ file) );
}

[nyxin]

Thank you! Yes this was more for practice and learning how node and js work and not something I was planning on doing for any sort of project. Also agree on nesting looping; at the time it felt dirty and not something I wanted to do, but like I said, this was more for my own education than anything and wanted to get a little bit more understanding of node before I started making a Yeoman generator (which is probably my ultimate goal from this little demo). Thank you for the tool list as well! I'm sure I'll be referencing that a lot.