copy snapshot click handler to toSnapshot for generic use

Author: timelyportfolio

src/snapshot/index.js

@@ -34,7 +34,8 @@ var Snapshot = {
     clone: require('./cloneplot'),
     toSVG: require('./tosvg'),
     svgToImg: require('./svgtoimg'),
-    toImage: require('./toimage')
+    toImage: require('./toimage'),
+    toSnapshot: require('./tosnapshot')
 };
 
 module.exports = Snapshot;

src/snapshot/tosnapshot.js

@@ -0,0 +1,74 @@
+/**
+* Copyright 2012-2016, Plotly, Inc.
+* All rights reserved.
+*
+* This source code is licensed under the MIT license found in the
+* LICENSE file in the root directory of this source tree.
+*/
+
+
+'use strict';
+
+var Plotly = require('../plotly');
+var Lib = require('../lib');
+
+/**
+ * @param {object} gd figure Object
+ * @param {object} opts option object
+ * @param opts.format 'jpeg' | 'png' | 'webp' | 'svg'
+ */
+function toSnapshot(gd, opts) {
+    
+    var Snapshot = Plotly.Snapshot;
+    var Lib = Plotly.Lib;
+  
+    // check for undefined opts
+    opts = (opts) ? opts : {};
+    
+    // default to png
+    opts.format = (opts.format) ? opts.format : 'png';
+    
+    if(Lib.isIE()) {
+        Lib.notifier('Snapshotting is unavailable in Internet Explorer. ' +
+                     'Consider exporting your images using the Plotly Cloud', 'long');
+        return;
+    }
+
+    if(gd._snapshotInProgress) {
+        Lib.notifier('Snapshotting is still in progress - please hold', 'long');
+        return;
+    }
+
+    gd._snapshotInProgress = true;
+    Lib.notifier('Taking snapshot - this may take a few seconds', 'long');
+
+    var ev = Snapshot.toImage(gd, opts);
+
+    var filename = gd.fn || 'newplot';
+    filename += '.' + opts.format;
+
+    ev.once('success', function(result) {
+        gd._snapshotInProgress = false;
+
+        var downloadLink = document.createElement('a');
+        downloadLink.href = result;
+        downloadLink.download = filename; // only supported by FF and Chrome
+
+        document.body.appendChild(downloadLink);
+        downloadLink.click();
+        document.body.removeChild(downloadLink);
+
+        ev.clean();
+    });
+
+    ev.once('error', function(err) {
+        gd._snapshotInProgress = false;
+
+        Lib.notifier('Sorry there was a problem downloading your ' + format, 'long');
+        console.error(err);
+
+        ev.clean();
+    });
+}
+
+module.exports = toSnapshot;