Drop bluebird/co, switch to async function

.travis.yml

@@ -1,3 +1,4 @@
 language: node_js
 node_js:
-  - '0.12'
+  - '8'
+  - 'node'

README.md

@@ -2,51 +2,59 @@
 
 > Calculate duration of an MP3
 
-
 ## Install
 
-```
-$ npm install --save mp3-duration
+```sh
+npm install mp3-duration
 ```
 
 ## Usage
 
+1. JavaScript
+
 ```javascript
 var mp3Duration = require('mp3-duration');
 
-mp3Duration('file.mp3', function (err, duration) {
-  if (err) return console.log(err.message);
-  console.log('Your file is ' + duration + ' seconds long');
+mp3Duration('file.mp3').then(duration => {
+  console.log(`Your file is ${duration} seconds long`);
+}).catch(e => {
+  console.err(e);
+});
+```
+
+2. TypeScript
+
+```typescript
+import mp3Duration = require('mp3-duration');
+
+mp3Duration('file.mp3').then(duration => {
+  console.log(`Your file is ${duration} seconds long`);
+}).catch(e => {
+  console.err(e);
 });
 ```
 
 ## API
 
-## mp3Duration(filePathOrBuffer [, cbrEstimate] [, callback])
+## mp3Duration(filePathOrBuffer [, cbrEstimate])
 
 ### filePathOrBuffer
 
-Type: `string` | `Buffer`
+Type: `string | Buffer`
 
 Path to the file or a buffer with the file's contents
 
 ### cbrEstimate
 
+Type: `boolean`
+
 Defaults to `false`. When set to `true`, will estimate the length of a
 constant-bitrate mp3. This speeds up the calculation a lot but isn't
 guaranteed to be accurate.
 
-### callback(error, duration)
-
-Type: `function`
-
-Callback to be called once duration is calculated. It's also possible to
-instead use the returned `Promise`. `duration` is the duration of the
-mp3 in `ms`.
-
 ### Return value
 
-`mp3Duration` returns a Promise that resolves to the duration of the mp3 in `ms` or rejects with some error.
+`mp3Duration` returns a Promise that resolves to the duration of the mp3 in `second` or rejects with some error.
 
 ## License
 

index.d.ts

@@ -0,0 +1,4 @@
+declare function mp3Duration(filePathOrBuffer: string | Buffer , cbrEstimate?: boolean): Promise<number>;
+declare function mp3Duration(filePathOrBuffer: string | Buffer): Promise<number>;
+
+export = mp3Duration;

index.js

@@ -1,13 +1,12 @@
 'use strict';
 
-var fs = require('fs')
-  , Promise = require('bluebird')
-  , co = require('bluebird-co').co
+const fs = require('fs');
+const { promisify } = require('util');
 
-  , open = Promise.promisify(fs.open) //(filename, flags [, mode])
-  , read = Promise.promisify(fs.read).bind(fs) //(fd, buffer, bufferOffset, length, position)
-  , fstat = Promise.promisify(fs.fstat).bind(fs) //(fs)
-  , close = Promise.promisify(fs.close).bind(fs);
+const open = promisify(fs.open);
+const read = promisify(fs.read);
+const fstat = promisify(fs.fstat);
+const close = promisify(fs.close);
 
 function skipId3(buffer) {
   var id3v2Flags
@@ -36,7 +35,7 @@ function skipId3(buffer) {
   return 0;
 }
 
-var versions = ['2.5', 'x', '2', '1']
+const versions = ['2.5', 'x', '2', '1']
   , layers = ['x', '3', '2', '1']
   , bitRates = {
     'V1Lx' : [0, 0, 0, 0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0],
@@ -142,83 +141,76 @@ function round(duration) {
   return Math.round(duration * 1000) / 1000; //round to nearest ms
 }
 
-function mp3Duration(filename, cbrEstimate, callback) {
-  if (typeof cbrEstimate === 'function') {
-    callback = cbrEstimate;
-    cbrEstimate = false;
+async function mp3Duration(filename, cbrEstimate = false) {
+  var duration = 0
+    , fd
+    , buffer
+    , bytesRead
+    , offset
+    , stat
+    , info
+    , srcBuffer
+    , isBuffer = false;
+
+  if (typeof filename === 'string') {
+    fd = await open(filename, 'r');
+  } else if (filename instanceof Buffer) {
+    srcBuffer = filename;
+    isBuffer = true;
   }
-  return co(function* () {
-    var duration = 0
-      , fd
-      , buffer
-      , bytesRead
-      , offset
-      , stat
-      , info
-      , srcBuffer
-      , isBuffer = false;
-
-    if (typeof filename === 'string') {
-      fd = yield open(filename, 'r');
-    } else if (filename instanceof Buffer) {
-      srcBuffer = filename;
-      isBuffer = true;
+
+  try {
+    if (!isBuffer) {
+      stat = await fstat(fd);
     }
 
-    try {
-      if (!isBuffer) {
-        stat = yield fstat(fd);
-      }
+    buffer = Buffer.alloc(100);
+
+    if (!isBuffer) {
+      bytesRead = await read(fd, buffer, 0, 100, 0);
+    } else {
+      bytesRead = srcBuffer.copy(buffer, 0, 0, 100);
+    }
+    if (bytesRead < 100) return 0;
 
-      buffer = new Buffer(100);
+    offset = skipId3(buffer);
 
+    while (offset < (isBuffer ? srcBuffer.length : stat.size)) {
       if (!isBuffer) {
-        bytesRead = yield read(fd, buffer, 0, 100, 0);
+        bytesRead = await read(fd, buffer, 0, 10, offset);
       } else {
-        bytesRead = srcBuffer.copy(buffer, 0, 0, 100);
+        bytesRead = srcBuffer.copy(buffer, 0, offset, offset + 10);
       }
-      if (bytesRead < 100) return 0;
-
-      offset = skipId3(buffer);
 
-      while (offset < (isBuffer ? srcBuffer.length : stat.size)) {
-        if (!isBuffer) {
-          bytesRead = yield read(fd, buffer, 0, 10, offset);
-        } else {
-          bytesRead = srcBuffer.copy(buffer, 0, offset, offset + 10);
-        }
+      if (bytesRead < 10) return round(duration);
 
-        if (bytesRead < 10) return round(duration);
-
-        //Looking for 1111 1111 111 (frame synchronization bits)
-        if (buffer[0] === 0xff && (buffer[1] & 0xe0) === 0xe0) {
-          info = parseFrameHeader(buffer);
-          if (info.frameSize && info.samples) {
-            offset += info.frameSize;
-            duration += ( info.samples / info.sampleRate );
-          } else {
-            offset++; //Corrupt file?
-          }
-        } else if (buffer[0] === 0x54 && buffer[1] === 0x41 && buffer[2] === 0x47) {//'TAG'
-          offset += 128; //Skip over id3v1 tag size
+      //Looking for 1111 1111 111 (frame synchronization bits)
+      if (buffer[0] === 0xff && (buffer[1] & 0xe0) === 0xe0) {
+        info = parseFrameHeader(buffer);
+        if (info.frameSize && info.samples) {
+          offset += info.frameSize;
+          duration += ( info.samples / info.sampleRate );
         } else {
           offset++; //Corrupt file?
         }
-
-        if (cbrEstimate && info) {
-          return round(estimateDuration(info.bitRate, offset, stat.size));
-        }
+      } else if (buffer[0] === 0x54 && buffer[1] === 0x41 && buffer[2] === 0x47) {//'TAG'
+        offset += 128; //Skip over id3v1 tag size
+      } else {
+        offset++; //Corrupt file?
       }
 
-      return round(duration);
-
-    } finally {
-      if (!isBuffer) {
-        yield close(fd);
+      if (cbrEstimate && info) {
+        return round(estimateDuration(info.bitRate, offset, stat.size));
       }
     }
 
-  }).asCallback(callback);
+    return round(duration);
+
+  } finally {
+    if (!isBuffer) {
+      await close(fd);
+    }
+  }
 }
 
 module.exports = mp3Duration;

package.json

@@ -11,7 +11,7 @@
     "url": "git://github.com/ddsol/mp3-duration"
   },
   "engines": {
-    "node": ">=0.11.0"
+    "node": ">=8.0.0"
   },
   "keywords": [
     "mp3",
@@ -27,11 +27,10 @@
   },
   "homepage": "https://github.com/ddsol/mp3-duration",
   "dependencies": {
-    "bluebird": "^3.5.1",
-    "bluebird-co": "^2.2.0"
+    "@types/node": ">=8.0.0"
   },
   "devDependencies": {
-    "mocha": "^2.2.4",
+    "mocha": "^5.2.0",
     "nyc": "^11.2.1"
   }
 }

tests/test.js

@@ -2,52 +2,35 @@ var assert = require('assert'),
   mp3Duration = require('../index.js'),
   fs = require('fs');
 
-describe('mp3Duration', function() {
-
-  it('returns a correct value for VBR duration', function(done) {
-    mp3Duration('./tests/demo - vbr.mp3', function(err, length) {
-      if (err) console.log(err.stack);
-      assert.equal(err, null, (err || {}).message);
-      assert.equal(length, 285.727, 'Length not as expected');
-      done();
-    });
+describe('mp3Duration', function () {
+
+  it('returns a correct value for VBR duration', async () => {
+    const length = await mp3Duration('./tests/demo - vbr.mp3');
+    assert.equal(length, 285.727, 'Length not as expected');
   });
 
-  it('returns a correct value for CBR duration with estimate', function(done) {
-    mp3Duration('./tests/demo - cbr.mp3', true, function(err, length) {
-      assert.equal(err, null, (err || {}).message);
-      assert.equal(length, 285.727, 'Length not as expected');
-      done();
-    });
+  it('returns a correct value for CBR duration with estimate', async () => {
+    const length = await mp3Duration('./tests/demo - cbr.mp3', true);
+    assert.equal(length, 285.727, 'Length not as expected');
   });
 
-  it('returns a correct value for CBR duration without estimate', function(done) {
-    mp3Duration('./tests/demo - cbr.mp3', function(err, length) {
-      assert.equal(err, null, (err || {}).message);
-      assert.equal(length, 285.78, 'Length not as expected');
-      done();
-    });
+  it('returns a correct value for CBR duration without estimate', async () => {
+    const length = await mp3Duration('./tests/demo - cbr.mp3');
+    assert.equal(length, 285.78, 'Length not as expected');
   });
 
-  it('returns a correct value for VBR duration when passing a buffer instead of a filename', function(done) {
+  it('returns a correct value for VBR duration when passing a buffer instead of a filename', async () => {
     const buffer = fs.readFileSync('./tests/demo - vbr.mp3');
 
-    mp3Duration(buffer, function(err, length) {
-      if (err) console.log(err.stack);
-      assert.equal(err, null, (err || {}).message);
-      assert.equal(length, 285.727, 'Length not as expected');
-      done();
-    });
+    const length = await mp3Duration(buffer);
+    assert.equal(length, 285.727, 'Length not as expected');
   });
 
-  it('return a correct value for CBR duration without estimate when passing a buffer instead of a filename', function(done) {
+  it('return a correct value for CBR duration without estimate when passing a buffer instead of a filename', async () => {
     const buffer = fs.readFileSync('./tests/demo - cbr.mp3');
 
-    mp3Duration(buffer, function(err, length) {
-      assert.equal(err, null, (err || {}).message);
-      assert.equal(length, 285.78, 'Length not as expected');
-      done();
-    });
+    const length = await mp3Duration(buffer);
+    assert.equal(length, 285.78, 'Length not as expected');
   });
 
 });