From 7831bb7b0bd94fc8054f5a1ad8dfc3f63543a37b Mon Sep 17 00:00:00 2001
From: Gerben <gerben@treora.com>
Date: Sat, 3 Jun 2017 00:26:22 +0200
Subject: [PATCH] Add blobToDataURL.

---
 lib/index.js | 14 ++++++++++++++
 test/test.js | 13 ++++++++++---
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index 933e323..d33f758 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -193,6 +193,19 @@ function dataURLToBlob(dataURL) {
   });
 }
 
+/**
+ * Convert a <code>Blob</code> to a data URL string
+ * (e.g. <code>'data:image/png;base64,iVBORw0KG...'</code>).
+ * Returns a Promise.
+ * @param {Blob} blob
+ * @returns {Promise} Promise that resolves with the data URL string
+ */
+function blobToDataURL(blob) {
+  return blobToBase64String(blob).then(function (base64String) {
+    return 'data:' + blob.type + ';base64,' + base64String;
+  });
+}
+
 /**
  * Convert an image's <code>src</code> URL to a data URL by loading the image and painting
  * it to a <code>canvas</code>. Returns a Promise.
@@ -300,6 +313,7 @@ module.exports = {
   imgSrcToDataURL    : imgSrcToDataURL,
   canvasToBlob       : canvasToBlob,
   dataURLToBlob      : dataURLToBlob,
+  blobToDataURL      : blobToDataURL,
   blobToBase64String : blobToBase64String,
   base64StringToBlob : base64StringToBlob,
   binaryStringToBlob : binaryStringToBlob,
diff --git a/test/test.js b/test/test.js
index ffbf54b..143c349 100644
--- a/test/test.js
+++ b/test/test.js
@@ -103,21 +103,28 @@ describe('basic tests', function () {
     });
   });
 
-  it('convert to dataURL', function () {
+  it('convert blob to data url', function () {
+    var blob = blobUtil.createBlob(['foo'], 'text/plain');
+    return blobUtil.blobToDataURL(blob).then(function (dataURL) {
+      dataURL.should.equal('data:text/plain;base64,Zm9v');
+    });
+  });
+
+  it('convert img to dataURL', function () {
     var img = document.getElementById('transparent');
     return blobUtil.imgSrcToDataURL(img.src).then(function (url) {
       url.should.match(/^data:image\/png;base64/);
     });
   });
 
-  it('convert to dataURL 2', function () {
+  it('convert img to dataURL 2', function () {
     var img = document.getElementById('kirby');
     return blobUtil.imgSrcToDataURL(img.src).then(function (url) {
       url.should.match(/^data:image\/png;base64/);
     });
   });
 
-  it('convert to dataURL 3', function () {
+  it('convert img to dataURL 3', function () {
     var img = document.getElementById('kirby');
     return blobUtil.imgSrcToDataURL(img.src, 'image/jpeg').then(function (url) {
       url.should.match(/^data:image\/jpeg;base64/);