Merge pull request #1 from mitsuki31/feature/add-internal-converter

Add internal MP3 converter feature

index.js

@@ -5,11 +5,15 @@
  * @since  0.1.0
  */
 
+'use strict';
+
 const fs = require('fs'),           // File system module
       os = require('os'),           // OS module
       path = require('path'),       // Path module
       ytdl = require('ytdl-core');  // Youtube Downloader module
 
+const { convertToMp3 } = require('./lib/acodecs-cvt');
+
 /**
  * Normalizes a YouTube Music URL to its original YouTube format.
  *
@@ -60,6 +64,9 @@ function normalizeYtMusicUrl(url) {
     const urlsFile = path.resolve(inputFile);
     console.log('File:', urlsFile);
 
+    // All illegal characters for file names
+    const illegalCharRegex = /[<>:"\/\\|?*\x00-\x1F]/g;
+
     await fs.readFile(urlsFile, 'utf8', (err, contents) => {
         if (err) throw err;
         if (contents === '') throw new Error('File is empty, no URL found');
@@ -78,26 +85,27 @@ function normalizeYtMusicUrl(url) {
             const info = await ytdl.getInfo(url);
             const authorVideo = info.videoDetails.author.name
                                     .replace(/\s-\s.+/, ''),
-                  titleVideo = info.videoDetails.title;
+                  titleVideo = info.videoDetails.title.replace(illegalCharRegex, '_');
 
             // Filter the audio and create new audio format
             const format = ytdl.chooseFormat(info.formats, {
                 quality: '140',      // This itag refers to 'mp4a' codec
                 filter: 'audioonly'  // Filter audio only
             });
 
-            // The file name format
-            const filename = `${authorVideo} - ${titleVideo}.m4a`;
-            const outStream = fs.createWriteStream(
-                path.join('download', filename));
+            const filename = path.join('download', `${titleVideo}.m4a`);
+            const outStream = fs.createWriteStream(filename);
 
             console.log(`Processing... '${titleVideo}' (${ytdl.getVideoID(url)})`);
             // Start downloading the audio and save to file
-            ytdl.downloadFromInfo(info, { format: format })
+            await ytdl.downloadFromInfo(info, { format: format })
                 .pipe(outStream);
             outStream.on('finish', () => {
-                console.log(`Finished: '${filename}' [${
+                console.log(`Finished: '${path.basename(filename)}' [${
                     (new Date()).toISOString()}]`);
+
+                // Convert to MP3
+                convertToMp3(filename);
             });
         });
     });

lib/acodecs-cvt.js

@@ -0,0 +1,67 @@
+/**
+ * `acodecs-cvt` is an abbreviation for Audio Codecs Converter.
+ * @author Ryuu Mitsuki
+ * @since  0.2.0
+ */
+
+'use strict';
+
+const fs = require('fs'),
+      path = require('path'),
+      ffmpeg = require('fluent-ffmpeg');
+
+const optionsMp3 = {
+    format: 'mp3',
+    bitrate: '128k',
+    frequency: 44100,
+    codec: 'libmp3lame',
+    channels: 2
+};
+
+function convertToMp3(inFile, options = optionsMp3) {
+    // Regular expressions for audio codecs
+    const audioCodecRegex = /(mp3|aac|wav|flac|ogg|wma|opus|amr|m4a)/i,      // All known extension names of audio file
+          noExtRegex = new RegExp(`(.+)(?:\\.${audioCodecRegex.source})$`);  // Get the file name without its extension
+
+    // Rename file extension to MP3 for the output file
+    const outFile = path.join(
+        path.dirname(inFile),
+        `${noExtRegex.exec(path.basename(inFile))[1]}.${options.format}`
+    );
+
+    // Store the file names only without their path directories
+    const ioBaseFile = [
+        path.basename(inFile),
+        path.basename(outFile)
+    ];
+
+    console.log(`Processing '${noExtRegex.exec(ioBaseFile[0])[1]}' ...`);
+    ffmpeg(inFile)  // Input
+        // Options
+        .toFormat(options.format)
+        .audioBitrate(options.bitrate)
+        .audioCodec(options.codec)
+        .audioChannels(options.channels)
+        .audioFrequency(options.frequency)
+
+        // Handlers
+        .on('error', (err) => {
+            console.error(err);
+        })
+        .on('progress', (info) => {
+            const percentage = Math.floor(info.percent);
+            // Write the progression percentage to the console
+            process.stdout.write(
+                `Progress: ${percentage < 0 ? 0 : percentage}%\r`);
+        })
+        .on('end', () => {
+            console.log('All done successfully.');
+        })
+        .save(outFile);  // Output
+}
+
+
+module.exports = {
+    optionsMp3,
+    convertToMp3
+};

package.json

@@ -13,6 +13,7 @@
   },
   "license": "MIT",
   "dependencies": {
+    "fluent-ffmpeg": "^2.1.2",
     "ytdl-core": "^4.11.5"
   }
 }