Supporting multilevel hierarchies

If the version sent in the /handshake response is 2.8.22 or later, your server should support a filter structure described by the Filter Group Object.

In version 2.8.5, the Filter Object describes the structure of the filters sent by the component.

The include.filter and exclude.filter properties of the Filter Object are responsible for filtering hierarchical data. Therefore, implement them to enable the support of multilevel hierarchies on your server.

The Mapping Object is responsible for grouping data into hierarchies. Specify hierarchy and parent properties to structure the data.

The example below illustrates how to compose multilevel hierarchies in the report. Here, we create the "Item" hierarchy with the "Category" field as a first level and the "Color" field as a second level:

report: {
    dataSource: {
        type: "api",
        url: "your_url",
        index: "your_index",
        mapping: {
            "Category": {
                type: "string",
                hierarchy: "Item"
            },
            "Color": {
                type: "string",
                hierarchy: "Item",
                parent: "Category"
            }
        }
    },
    slice: {
        // your slice
    }
}

See a live example on JSFiddle.

As an alternative to the Mapping Object, you can configure hierarchies right in the response to the /fields request. To do so, specify fields.hierarchy and fields.parent properties.

Here is an example of a /fields response where the "Category" and "Color" fields are grouped under the "Item" hierarchy (with "Category" as the top level of the hierarchy):

{  
    "fields":[
        {
            "uniqueName": "Category",
            "type": "string",
            "hierarchy": "Item"
        },
        {
            "uniqueName": "Color",
            "type": "string",
            "hierarchy": "Item",
            "parent": "Category"
        },
        ...
    ],
    "aggregations":{
        ...
    },
    "filters":{
        ...
    } 
}