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A service can add a list of quick links to the Ambari web UI by adding metainfo meta info to a text file following a predefined JSON format. Ambari server parses the quicklink quick link JSON file and provides its content to the UI. So that Ambari web UI can calculate quick link URLs based on the information and populate the quicklinks quick links drop-down list accordingly.

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Use YARN as an example, the following is what the metainfo.xml looks like with the quiclinks quick links configurations.

<services>
    <service>
    <name>YARN</name>
    <version>2.7.1.2.3</version>
    <quickLinksConfigurations>
        <quickLinksConfiguration>
            <fileName>quicklinks.json</fileName>
            <default>true</default>
        </quickLinksConfiguration>
    </quickLinksConfigurations>

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The metainfo.xml can have different quicklinks quick links configuration as shown here for MapReduce2.
The quickLinksConfigurations-dir is an optional field that tells Ambari Server where to load the quicklinks.json file. We can skip it if we want the service to use the default quicklinks directory.

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A quick link JSON file has two major sections, the "configuration" section for determine the protocol (HTTP vs HTTPS), and the "links" section for meta information of each quicklink quick link to be displayed on the Ambari web UI. The JSON file also includes a "name" section at the top that defines the name of the quicklinks quick links JSON file that server uses for identification. 

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REST API

You can examine the quicklink quick link information made available to the Ambari web UI by running the following REST API as an HTTP GET request.

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