The JavaScript API exposed through Visualize.js allows you to embed and dynamically interact with reports. With Visualize.js, you can create web pages and web applications that seamlessly embed reports and complex interaction. You can control the look and feel of all elements through CSS and invent new ways to merge data into your application. Visualize.js helps you make advanced business intelligence available to your users.
This chapter contains the following sections:
| • | Requesting the Visualize.js Script |
| • | Contents of the Visualize.js Script |
| • | Usage Patterns |
| • | Testing Your JavaScript |
| • | Changing the Look and Feel |
| • | Cross-Domain Security |
Each function of Visualize.js is then described in the following chapters:
| • | API Reference - login and logout |
| • | API Reference - resourcesSearch |
| • | API Reference - report |
| • | API Reference - inputControls |
| • | API Reference - dashboard |
| • | API Reference - Errors |
The last chapters demonstrate more advanced usage of Visualize.js:
| • | API Usage - Report Events |
| • | API Usage - Hyperlinks |
| • | API Usage - Interactive Reports |
| • | Visualize.js Tools |
Requesting the Visualize.js Script
The script to include on your HTML page is named visualize.js. It is located on your running instance of JasperReports Server. Later on your page, you also need a container element to display the report from the script.
The content of visualize.js is type='text/javascript', but that is the default so you usually don't need to include it.
You can specify several parameters when requesting the script:
| Parameter | Type or Value | Description |
|---|---|---|
| userLocale | locale string | Specify the locale to use for display and running reports. It must be one of the locales supported by JasperReports Server. The default is the locale configured on the server. |
| logEnabled | true|false | Enable or disable logging. By default, it is enabled (true). |
| logLevel | debug|info|warn|error | Set the logging level. By default the level is error. |
| baseUrl | URL | The URL of the JasperReports Server that will respond to visualize requests. By default, it is the same server instance that provides the script. |
The following request shows how to use script parameters:
[/code] |
Contents of the Visualize.js Script
The Visualize.js script itself is a factory function for an internal JrsClient.
You write JavaScript in a callback that controls what the client does. The following code sample shows the functions of the JrsClient that are available to you:
These functions are described in the remaining API reference chapters.
Usage Patterns
After specifying the authentication information, you write the callback that will execute inside the client provided by visualize.js.
The following sample shows how to use the always callback:
Testing Your JavaScript
As you learn to use Visualize.js and write the JavaScript that embeds your reports into your web app, you should have a way to run and view the output of your script.
In order to load Visualize.js , your HTML page containing your JavaScript must be accessed through a web server. Opening a static file with a web browser does not properly load the iframes needed by the script.
One popular way to view your Visualize.js output, is to use the jsFiddle online service. You specify your HTML, JavaScript, and optional CSS in 3 separate frames, and the result displays in the fourth frame.
Another way to test your JavaScript is to use the app server bundled with JasperReports Server. If you deploy the server from the installer with the Apache Tomcat app server, you can create an HTML file at the root of the server web app, for example:
<js-install>/apache-tomcat/webapps/jasperserver-pro/testscript.html
Write your HTML and JavaScript in this file, and then you can run Visualize.js by loading the file through the following URL:
http://mydomain.com:8081/jasperserver-pro/testscript.html
Changing the Look and Feel
When you create a web application that embeds Visualize.js content, you determine the look and feel of your app through layout, styles, and CSS (Cascading Style Sheets). Most of the content that you embed consists of reports and dashboards that you create in JasperReports Server or Jaspersoft Studio, where you set the appearance of colors, fonts, and layout to match your intended usage.
But some Visualize.js elements also contain UI widgets that are generated by the server in a default style, for example the labels, buttons, and selection boxes for the input controls of a report. In general, the default style is meant to be neutral and embeddable in a wide range of visual styles. If the default style of these UI widgets does not match your app, there are two approaches:
| • | Customizing the UI with CSS – You can change the appearance of the UI widgets through CSS in your app. |
| • | Customizing the UI with Themes – You can redefine the default appearance of the UI widgets in themes on the server. |
These two options are covered in the following subsections.
Customizing the UI with CSS
The UI widgets generated by the server have CSS classes and subclasses, also generated by the server, that you can redefine in your app to change their appearance. To change the appearance of the generated widgets, create CSS rules that you would add to CSS files in your own web app. To avoid the risk of unintended interference with other CSS rules, you should define your CSS rules with both a classname and a selector, for example:
To change the style of specific elements in the server's generated widgets, you can find the corresponding CSS classes and redefine them. To find the CSS classes, write the JavaScript display the UI widgets, for example input controls, then test the page in a browser. Use your browser's code inspector to look at each element of the generated widgets and locate the CSS rules that apply to it. The code inspector shows you the classes and often lets you modify values to preview the look and feel that you want to create. For more information, see Embedded Input Control Styles.
Customizing the UI with Themes
The UI widgets in Visualize.js elements are generated on the server and their look and feel is ultimately determined by themes. Themes are CSS files defined for organizations, and thus appearances are determined by the user credentials submitted by your Visualize.js instance. Certain visual properties of the UI widgets embedded in your app by Visualize.js can be modified by changing themes on the server. For more information about themes, see the JasperReports Server Administrator Guide.
However, not all properties of a UI widget can be modified through themes. If you want to create a fully custom visualization, you might need to access raw data through the Visualize.js APIs and write your own elements and CSS to display them. For more information, see Exporting Data From a Report.
Cross-Domain Security
After developing your web application and embedding Visualize.js, you will deploy it to your users through some web domain, for example bi-enabled.myexample.com. For testing, JasperReports Server accepts Visualize.js requests from any domain, and your web app will display embedded reports and dashboards. However, once you go into production, you should add security and make sure that the server responds only to Visualize.js requests from your web app. This is called cross-site request forgery (CSRF) protection.
JasperReports Server includes a configurable whitelist of domains, and it only responds to Visualize.js requests from those domains. Add your web domain to this whitelist, and no other web apps on malicious domains can access your server. In addition to whitelisted domains, JasperReports Server always responds to requests that originate from the same domain as the server itself.
To configure the cross-domain whitelist:
| 1. | Log in as system administrator (superuser). |
| 2. | Select Manage > Server Settings then Server Attributes. |
| 3. | The server attribute nameddomainWhitelist contains a regular expression that matches allowed domains. Set it as follows: |
| • | When your Visualize.js web app is on another domain, such as in this example, create a regular expression to match the protocol, domain name and port numbers. You can also match multiple subdomains or several port numbers as in this example: |
domainWhitelist = http://*.myexample.com:80d0
The server translates this simplified expression into the proper regular expression ^http://.*.myexample.com:80d0$. If you want to avoid the translation, put ^ $ around your value.
| • | When your Visualize.js web app is on the same domain as your JasperReports Server set the value to <blank> (no value) so that no other domain has access: |
domainWhitelist = <blank>
| • | It is also possible to limit the domains accessing the JasperReports Server for each organization. For advanced configuration details, see the section on cross-domain whitelists in the JasperReports Server Security Guide. |
For more information about setting attributes see the JasperReports Server Administrator Guide.
Cross-Site Errors
Even when the domain whitelist is configured, some browsers may limit cross-site access for security reasons. In particular, the Safari browser often blocks access to the Visualize.js script because it uses third-party cookies to enable cross-site access.
There are several workarounds in this case:
| 1. | Use a different browser. Other browsers may allow access when Safari does not. However, in the future, other browsers may also begin to restrict access to third-party cookies that enable cross-site access. |
| 2. | Use a proxy to make JasperReports Server appear to be on the same domain as your website. If you have already embedded Visualize.js in a cross-site way, changing to proxying will require changes to your environment (implementing and configuring a proxy service) and to your application. |
| 3. | Use the same domain but different sub-domains for your application and JasperReports Server, for example: |
| • | www.myapp.com for your application |
| • | jaspersoft.myapp.com for JasperReports Server serving the Visualize.js script |
Recommended Comments
There are no comments to display.