How to save an image of the chart on the server with highcharts?
With highcharts, you have a built-in button to download the current chart (example: http://www.highcharts.com/demo/, this button: ). You can save it as PNG, JPEG, PDF or SVG.
What I'd like to do is to create a link that saves the image on the server, instead of downloading it. How could I do that ?
I suppose that I have to modify the exportChart
function in the exporting.src.js file. It looks like this (but I don't know javascript enough to do that) :
exportChart: function (options, chartOptions) {
var form,
chart = this,
svg = chart.getSVG(chartOptions);
// merge the options
options = merge(chart.options.exporting, options);
// create the form
form = createElement('form', {
method: 'post',
action: options.url
}, {
display: NONE
}, doc.body);
// add the values
each(['filename', 'type', 'width', 'svg'], function (name) {
createElement('input', {
type: HIDDEN,
name: name,
value: {
filename: options.filename || 'chart',
type: options.type,
width: options.width,
svg: svg
}[name]
}, null, form);
});
// submit
form.submit();
// clean up
discardElement(form);
},
It could be done really easy with PhantomJS
. You can render Highchart
chart and save it to SVG, PNG, JPEG or PDF. The example below renders a demo Highcharts
diagram to SVG and PDF at the same time:
var system = require('system');
var page = require('webpage').create();
var fs = require('fs');
// load JS libraries
page.injectJs("js/jquery.min.js");
page.injectJs("js/highcharts/highcharts.js");
page.injectJs("js/highcharts/exporting.js");
// chart demo
var args = {
width: 600,
height: 500
};
var svg = page.evaluate(function(opt){
$('body').prepend('<div id="container"></div>');
var chart = new Highcharts.Chart({
chart: {
renderTo: 'container',
width: opt.width,
height: opt.height
},
exporting: {
enabled: false
},
title: {
text: 'Combination chart'
},
xAxis: {
categories: ['Apples', 'Oranges', 'Pears', 'Bananas', 'Plums']
},
yAxis: {
title: {
text: 'Y-values'
}
},
labels: {
items: [{
html: 'Total fruit consumption',
style: {
left: '40px',
top: '8px',
color: 'black'
}
}]
},
plotOptions: {
line: {
dataLabels: {
enabled: true
},
enableMouseTracking: false
},
series: {
enableMouseTracking: false,
shadow: false,
animation: false
}
},
series: [{
type: 'column',
name: 'Andrii',
data: [3, 2, 1, 3, 4]
}, {
type: 'column',
name: 'Fabian',
data: [2, 3, 5, 7, 6]
}, {
type: 'column',
name: 'Joan',
data: [4, 3, 3, 9, 0]
}, {
type: 'spline',
name: 'Average',
data: [3, 2.67, 3, 6.33, 3.33],
marker: {
lineWidth: 2,
lineColor: 'white'
}
}, {
type: 'pie',
name: 'Total consumption',
data: [{
name: 'Andrii',
y: 13,
color: '#4572A7'
}, {
name: 'Fabian',
y: 23,
color: '#AA4643'
}, {
name: 'Joan',
y: 19,
color: '#89A54E'
}],
center: [100, 80],
size: 100,
showInLegend: false,
dataLabels: {
enabled: false
}
}]
});
return chart.getSVG();
}, args);
// Saving SVG to a file
fs.write("demo.svg", svg);
// Saving diagram as PDF
page.render('demo.pdf');
phantom.exit();
If you save the code as demo.js
, then just run bin/phantomjs demo.js
to generate demo.svg
and demo.pdf
I just implement this using Nobita's method. I was creating a survey that showed the user's results in a chart, uploaded the image to my server and then sent out an email with the image in it. Here's a few things to note.
I had to make a few updates to the highcharts/exporting-server/index.php file which are the following:
I changed the directory from "temp" to something else and just note that it is in 4 different locations.
I had to change shell_exec() adding "-XX:MaxHeapSize=256m" because it was giving me an error:
$output = shell_exec("java -XX:MaxHeapSize=256m -jar ". BATIK_PATH ." $typeString -d $outfile $width /mypathhere/results/$tempName.svg");
If you want it to download that image you can leave the following alone:
header("Content-Disposition: attachment; filename=$filename.$ext");
header("Content-Type: $type");
echo file_get_contents($outfile);
But, I changed this because I wanted to send back the path to the image, so I deleted the above and replace this with the image path (Note that I'm just using the temporary name.):
echo "/mypathhere/results/$tempName.$ext";
Also, this file is deleting the svg file and also the new file you made. You need to remove the code that deletes the file:
unlink($outfile);
And you can also delete the line before it if you want to keep the svg file.
Make sure to include highcharts/js/modules/exporting.js
Then, in your JS you can do something like the following:
var chart = new Highcharts.Chart();
var imageURL = '';
var svg = chart.getSVG();
var dataString = 'type=image/jpeg&filename=results&width=500&svg='+svg;
$.ajax({
type: 'POST',
data: dataString,
url: '/src/js/highcharts/exporting-server/',
async: false,
success: function(data){
imageURL = data;
}
});
The URL you are posting to is the new version of the /exporting-server/index.php. Then, you can use the imageURL however you like.