FileMan - Downloaded File Renaming Tool

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I have downloaded hundreds of pdf materials on Software Development, Machine Learning, Cloud, and DevOps. These ebooks do not have the appropriate filenames e.g 1234.pdf I wanted an informative filename life the ebook title + the author + number of pages.

The Objective

Using Javascript how to rename all the pdf files from a downloaded folder

Before

After

**### The Steps

1. Write an asynchronous function getTitle (fileBuffer) that takes a file buffer. The function uses an external dependency pdf-parse, which is a pure javascript cross-platform module to extract texts from PDFs.

2. Inside the function, remove all special characters except space from a string text using regex

    text.replace(/[^a-zA-Z0-9 ]/g, "")

Alternatively, you could still replace the specific characters

    text.replace(/[&\/\\#,+()$~%.'":*?<>{}]/g, '');

• Convert string to Title Case with JavaScript

1. The second Step is to use readdirSync() function from fs module to read all the files in the folder. Then for each file, determine the file type from the extension and pass the pdf files to readFileSync() function to read the file buffer synchronously.

2. Finally, use the getTitle(dataBuffer) to generate the tile and use renameSync() function to rename the file title.

The Complet Programme is shown below.

const { readdirSync, renameSync, readFileSync } = require('fs');
const { join, extname, basename, resolve } = require('path');
const pdf = require('pdf-parse');

// Get path to file directory
const folder = resolve(__dirname, '../');

// Get an array of the files inside the folder
const files = readdirSync(folder);

// Loop through each file that was retrieved 
  for (const file of files) {
      const extension = extname(file);
      const name = basename(file, extension);

      if (extension === '.pdf') {
        const oldPath = folder + `/${file}`;        
        const dataBuffer = readFileSync(oldPath);
        getTitle(dataBuffer).then(title =>{
            renameSync(join(folder, file), join(folder, `${title}${extension}`));
        }).catch(err => console.log(err.message));
      }
  }


  async function getTitle (fileBuffer) {
    return pdf(fileBuffer).then(function(data) {
        let title;
        if (data.info && data.info.Title) {
            title = data.info.Title;
        } else {
            title = data.text ? data.text.replace(/\r?\n|\r/g, " ").substring(0, 120).trim() : '';
        }
        title = title.split(' ')
        .map(s => s.slice(0, 1).toUpperCase() + s.slice(1).toLowerCase())
        .join(' ');
        if (data.info && data.info.Author) {
            title = `${title} By ${data.info.Author}`;
        }
        return `${title.replace(/[^a-zA-Z0-9 ]/g, "")} - ${data.numpages}` 
    });
};

TODO

Write other features you will want to see in the comments below.