by Torstein Hønsi
There may be cases where you don't want to use Highcharts' export server running at export.highcharts.com, for instance if you are running a secure website or if you don't want your data to be passed to the Highcharts CDN.
Before setting up your own server, consider using the client side export module. In short, a dedicated server is only needed if you need to support IE8 and older, or if you are having problems with the features listed in the client side export browser support table.
Install with npm install highcharts-export-server -g or clone from https://github.com/highcharts/node-export-server
Documentation on GitHub
The export server running at export.highcharts.com is a Node.js-based service, which is easy to install and integrate on any system. It accepts either chart configurations or SVGs, together with additional resources, and uses PhantomJS to render charts to images (PNG, JPG, PDF and SVG) to be sent back to the user.
We also have two older flavors of servers to choose from;
This solution also includes a standalone solution for creating charts on the server, without a client involved. Highcharts is using this export server at export.highcharts.com, the default Highcharts export server. It's a server which is desgined with a large network load in mind. Requests to this server are concurrently handled by an serverpool.
It takes either SVG or Highcharts options (in javascript) as input and converts it to images (PNG, JPEG ), PDF or SVG.
The java based Highcharts export-server has the following prerequisites:
TIP: use Jetty (application server) during development, requires no installation
Edit the app-convert.properties file in highcharts-export/highcharts-export-web/src/main/webapp/WEB-INF/spring and change the properties if necessary. Read the comments in the property file, for deciding what you need to change.
You can for example change the location of the PhantomJS executable, the name of the convert script, timeouts and poolsize of how many PhantomJS processes you want to run.
Highcharts JS is needed on the server for supporting server-side rendering of charts. Instead of posting a SVG from the browser to the server, you can also post a Highcharts configuration in javascript and let PhantomJS generate the chart on the server. Read more on server-side rendering here.
To make this work we need to run a headless browser, PhantomJS and PhantomJS needs in it's turn the Highcharts JS files on the server. For licensing reasons the Highcharts export server doesn't ship with Highcharts javascript files. We need to copy the Highcharts files manually to the project.
Save highcharts.js or highstock.js for stock charts, highcharts-more.js (for bubble, range, polar charts), funnel.js for supporting funnel charts, etc. to this location: highcharts-export-server/java/highcharts-export/highcharts-export-convert/src/main/resources/phantomjs It's recommended to use the Highcharts compiled files from code.highcharts.com/[highcharts-version-you-use]/
The javascript files are already configured in the resources.json file which is used by PhantomJS to determine which files need to be injected to PhantomJS. If convenient, you can specify alternative paths in the resources.json. So make sure the resources.json matches the files you just copied in this step.
Open a Dos/Shell prompt and navigate to the main folder of the export server, highcharts-export and install it in your local Maven repository. This installs also all dependencies (libraries) for the module.
After you have configured and installed the application, you can compile the project files. Open a commandline in a terminal or DOS and navigate to the highchart-export-web folder and while standing here, type the following in a terminal: mvn clean package
After compiling and the message BUILD SUCCESS, you will find a file: highcharts-export-web.war in the highcharts-export/highcharts-export-web/target folder.
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.476s
[INFO] Finished at: Wed Jun 26 14:52:07 CEST 2013
[INFO] Final Memory: 15M/215M
[INFO] ------------------------------------------------------------------------
highcharts-export-web $> ls target/
classes highcharts-export-web maven-archiver
generated-sources highcharts-export-web.war surefire
Gerts-MacBook-Pro:highcharts-export-web gert$
Upload/copy this to the application server. You're done with setting up the highcharts-export server!
We added the Jetty Server dependency in pom.xml file for testing convenience. For running the export-server locally, during development, navigate in a DOS/Shell to the highcharts-export/highcharts-export-web folder, and run this command: mvn jetty:run. This starts the Jetty application server and the application is now accessible at http://localhost:8080/export.
Change you url property for the exporting option in your (javascript) highcharts configuration, and point it to the new installed exporting-server, otherwise it still points at Highcharts export-server at http://export.highcharts.com
exporting:{
url:'http://new.server.com/highcharts-export/'
}Remember to install necessary fonts on the server. When characters are missing, they will be displayed as squares on the exported charts. The application will automatically pick the fonts up after installation.
Highcharts sets its font globally to Lucida Grande, so if you use for example a japanese font, you have to set the fontFamily to a japanese-able font with Highcharts.setOptions, for making the export work.
When having problems while using the export-server, the first thing you could do is to enable logging Debug messages. This can give you a clue of what's going wrong. To enable Debug messages, uncomment these lines in highcharts-export/highcharts-export-web/src/main/resources/log4j.properties
# Debug specific class
log4j.logger.services=DEBUG
log4j.logger.converter=DEBUG
log4j.logger.exporter=DEBUG
log4j.logger.pool=DEBUG
By default WebLogic registers its own URLStreamHandler to handle http URLs. This results in that the Connection silently returns and empty files being returned from the server. The solution is to get in a reference to Java's default URLStreamHandler instead of the one from WebLogic. Follow these steps
1. Alter this file: highcharts-export\highcharts-export-convert/src/main/java/com/highcharts/export/server.Server.java
Change line 94,95 from
URL url = new URL("http://" + host + ":"
+ port + "/");
to
sun.net.www.protocol.http.Handler handler = new sun.net.www.protocol.http.Handler();
URL url = new URL(null, "http://" + host + ":" + port + "/", handler);
2. Goto the folder java/highcharts-export
3. Update your local maven repository, Run: mvn install
4. Goto the folder java/highcharts-export/highcharts-export-web
5. Create the .war file, Run: mvn clean package
Note that this export server omits server-side rendering. It can be used (only) to convert SVG files to images and PDF.
The index.php file that handles the POST can be downloaded from our GitHub repository.
index.php file from the exporting-server repository to your server.temp in the same directory as index.php and chmod this new directory to 777 (Linux/Unix servers only).batik-rasterizer.jar and the entire lib directory to a location on your web server.If for any reason the export-server fails to export images, then consider pasting this code snippet to output error messages. Paste this before Line 78, beginning with the commenting text: // Do the conversion.
// Troubleshoot snippet
$command = "java -jar ". BATIK_PATH ." $typeString -d $outfile $width temp/$tempName.svg 2>&1";
$output = shell_exec($command);
echo "Command: $command <br>";
echo "Output: $output";
die;
As an ASP.NET alternative to our Java/PHP based server module, Clément Agarini has kindly shared his export module for ASP.NET.