Vega reference

For additional Vega and Vega-Lite information, refer to the reference sections.

Kibana has extended Vega and Vega-Lite with extensions that support:

Most users will want their Vega visualizations to take the full available space, so unlike Vega examples, width and height are not required parameters in Kibana. To set the width or height manually, set autosize: none. For example, to set the height to a specific pixel value:

autosize: none
width: container
height: 200

The default Kibana settings which are inherited by your visualizations are:

autosize: {
  type: fit
  contains: padding
}
width: container
height: container

Kibana is able to merge your custom autosize settings with the defaults. The options fit-x and fit-y are supported but not recommended over the default fit setting.

To learn more, read about autosize in the Vega documentation.

Kibana registers a default Vega color scheme with the id elastic, and sets a default color for each mark type. Override it by providing a different stroke, fill, or color (Vega-Lite) value.

Kibana extends the Vega data elements with support for direct Elasticsearch queries specified as url.

Kibana is unable to support dynamically loaded data, which would otherwise work in Vega. All data is fetched before it’s passed to the Vega renderer.

To define an Elasticsearch query in Vega, set the url to an object. Kibana parses the object looking for special tokens that allow your query to integrate with Kibana.

Tokens include the following:

For example, the following query counts the number of documents in a specific index:

// An object instead of a string for the URL value
// is treated as a context-aware Elasticsearch query.
url: {
  // Specify the time filter.
  %timefield%: @timestamp
  // Apply dashboard context filters when set
  %context%: true

  // Which indexes to search
  index: kibana_sample_data_logs
  // The body element may contain "aggs" and "query" keys
  body: {
    aggs: {
      time_buckets: {
        date_histogram: {
          // Use date histogram aggregation on @timestamp field
          field: @timestamp 
          // interval value will depend on the time filter
          // Use an integer to set approximate bucket count
          interval: { %autointerval%: true }
          // Make sure we get an entire range, even if it has no data
          extended_bounds: {
            min: { %timefilter%: "min" }
            max: { %timefilter%: "max" }
          }
          // Use this for linear (e.g. line, area) graphs
          // Without it, empty buckets will not show up
          min_doc_count: 0
        }
      }
    }
    // Speed up the response by only including aggregation results
    size: 0
  }
}

The full result includes the following structure:

{
  "aggregations": {
    "time_buckets": {
      "buckets": [{
          "key_as_string": "2015-11-30T22:00:00.000Z",
          "key": 1448920800000,
          "doc_count": 28
        }, {
          "key_as_string": "2015-11-30T23:00:00.000Z",
          "key": 1448924400000, 
          "doc_count": 330
        }, ...

For most visualizations, you only need the list of bucket values. To focus on only the data you need, use format: {property: "aggregations.time_buckets.buckets"}.

Specify a query with individual range and dashboard context. The query is equivalent to "%context%": true, "%timefield%": "@timestamp", except that the time range is shifted back by 10 minutes:

{
  body: {
    query: {
      bool: {
        must: [
          // This string will be replaced
          // with the auto-generated "MUST" clause
          "%dashboard_context-must_clause%"
          {
            range: {
              // apply timefilter (upper right corner)
              // to the @timestamp variable
              @timestamp: {
                // "%timefilter%" will be replaced with
                // the current values of the time filter
                // (from the upper right corner)
                "%timefilter%": true
                // Only work with %timefilter%
                // Shift current timefilter by 10 units back
                shift: 10
                // week, day (default), hour, minute, second
                unit: minute
              }
            }
          }
        ]
        must_not: [
          // This string will be replaced with
          // the auto-generated "MUST-NOT" clause
          "%dashboard_context-must_not_clause%"
        ]
        filter: [
          // This string will be replaced
          // with the auto-generated "FILTER" clause
          "%dashboard_context-filter_clause%"
        ]
      }
    }
  }
}

The "%timefilter%" can also be used to specify a single min or max value. The date_histogram’s extended_bounds can be set with two values - min and max. Instead of hardcoding a value, you may use "min": {"%timefilter%": "min"}, which will be replaced with the beginning of the current time range. The shift and unit values are also supported. The "interval" can also be set dynamically, depending on the currently picked range: "interval": {"%autointerval%": 10} will try to get about 10-15 data points (buckets).

[preview] This functionality is in technical preview and may be changed or removed in a future release. Elastic will work to fix any issues, but features in technical preview are not subject to the support SLA of official GA features. To enable Maps, the graph must specify type=map in the host configuration:

{
  "config": {
    "kibana": {
      "type": "map",

      // Initial map position
      "latitude": 40.7,   // default 0
      "longitude": -74,   // default 0
      "zoom": 7,          // default 2

      // defaults to "default". Use false to disable base layer.
      "mapStyle": false,

      // default 0
      "minZoom": 5,

      // defaults to the maximum for the given style,
      // or 25 when base is disabled
      "maxZoom": 13,

      // defaults to true, shows +/- buttons to zoom in/out
      "zoomControl": false,

      // Defaults to 'false', disables mouse wheel zoom. If set to
      // 'true', map may zoom unexpectedly while scrolling dashboard
      "scrollWheelZoom": false,

      // When false, repaints on each move frame.
      // Makes the graph slower when moving the map
      "delayRepaint": true, // default true
    }
  },
  /* the rest of Vega JSON */
}

The visualization automatically injects a "projection", which you can use to calculate the position of all geo-aware marks. Additionally, you can use latitude, longitude, and zoom signals. These signals can be used in the graph, or can be updated to modify the position of the map.

[preview] This functionality is in technical preview and may be changed or removed in a future release. Elastic will work to fix any issues, but features in technical preview are not subject to the support SLA of official GA features. You can use Vega’s data element to access Elastic Maps Service (EMS) vector shapes of administrative boundaries in your Vega map by setting url.data to emsFile:

url: {
  // "type" defaults to "elasticsearch" otherwise
  type: emsfile
  // Name of the file, exactly as in the Region map visualization
  name: World Countries
}
// The result is a geojson file, get its features to use
// this data source with the "shape" marks
// https://vega.github.io/vega/docs/marks/shape/
format: {property: "features"}

Kibana has installed the Vega tooltip plugin, so tooltips can be defined in the ways documented there. Beyond that, Kibana also supports a configuration option for changing the tooltip position and padding:

{
  config: {
    kibana: {
      tooltips: {
        position: 'top',
        padding: 15
      }
    }
  }
}

Vega can load data from any URL, but this is disabled by default in Kibana. To change this, set vis_type_vega.enableExternalUrls: true in kibana.yml, then restart Kibana.

Use the contextual Inspect tool to gain insights into different elements. For Vega visualizations, there are two different views: Request and Vega debug.

Vega uses the Elasticsearch search API to get documents and aggregation results from Elasticsearch. To troubleshoot these requests, click Inspect, which shows the most recent requests. In case your specification has more than one request, you can switch between the views using the View dropdown.

With the Vega debug view, you can inspect the Data sets and Signal Values runtime data.

The runtime data is read from the runtime scope.

To debug more complex specs, access to the view variable. For more information, refer to the Vega browser debugging process.

Because of the dynamic nature of the data in Elasticsearch, it is hard to help you with Vega specs unless you can share a dataset. To do this, click Inspect, select the Vega debug view, then select the Spec tab:

To copy the response, click Copy to clipboard. Paste the copied data to gist.github.com, possibly with a .json extension. Use the [raw] button, and share that when asking for help.

[preview] This functionality is in technical preview and may be changed or removed in a future release. Elastic will work to fix any issues, but features in technical preview are not subject to the support SLA of official GA features. Use browser debugging tools (for example, F12 or Ctrl+Shift+J in Chrome) to inspect the VEGA_DEBUG variable:

Kibana has extended the Vega expression language with these functions:

/**
  * @param {object} query Elastic Query DSL snippet, as used in the query DSL editor
  * @param {string} [index] as defined in Kibana, or default if missing
  */
kibanaAddFilter(query, index)

/**
  * @param {object} query Elastic Query DSL snippet, as used in the query DSL editor
  * @param {string} [index] as defined in Kibana, or default if missing
  */
kibanaRemoveFilter(query, index)

kibanaRemoveAllFilters()

/**
  * Update dashboard time filter to the new values
  * @param {number|string|Date} start
  * @param {number|string|Date} end
  */
kibanaSetTimeFilter(start, end)

{
  config: {
    kibana: {
      // Placement of the Vega-defined signal bindings.
      // Can be `left`, `right`, `top`, or `bottom` (default).
      controlsLocation: top
      // Can be `vertical` or `horizontal` (default).
      controlsDirection: vertical
      // If true, hides most of Vega and Vega-Lite warnings
      hideWarnings: true
      // Vega renderer to use: `svg` or `canvas` (default)
      renderer: canvas
    }
  }
}