Chart core

Every chart primitive spreads chartCoreShape into its schema.

Field What it is
title, description Shown on every surface; description is what the chart shows, for accessible and text surfaces
data Typed columnar data, as the source table holds it
colors Data colors resolved by whoever built the node
source Provenance, never rendered
losses What the source had that the node drops or approximates 
data: {
  columns: Array<{
    id: string;
    label: string;
    type: 'number' | 'string' | 'date' | 'boolean';
    role: 'dimension' | 'metric';
    format?: PortableFormat;
    multivalue?: true;
    source?: unknown;
  }>;
  rows: Cell[][];
  source?: unknown;
  display?: Record<string, string[]>;
}
  1. stable within the node; everything refers to a column by id
  2. opaque, never rendered
  3. Cell = number | string | boolean | null, or an array of those
  4. opaque table-level meta
  5. pre-rendered strings per column, one per row

Rows are never reordered, so a selection can refer to them by index. null is a missing value, never zero.

role says what a column is for. dimension columns identify a row (buckets, categories, time) and metric columns measure it. Dimensions lead text summaries, a phone layout picks its row header from the first one, and they are what a selection targets.

source, on a column or on the table, is opaque to Isomer. A host keeps there what it needs to act on a selection, such as Kibana Datatable meta, so it can rebuild a filter from a selected cell.

display holds strings for values whose format is outside the portable set (custom, static lookup, URL, color). They replace the formatted value on every surface, and the node records the loss in losses.

Rules:

  • Column ids are unique.
  • Every row has exactly one cell per column, in column order.
  • A cell holds its column type or null: a number in a number column, a string in a string column, a boolean in a boolean column, and epoch milliseconds or an ISO 8601 date-time string with a UTC offset (Z or +hh:mm) in a date column. Only a multivalue column holds arrays of those.
  • Each display key names a column and holds one string per row.
kind Fields As Kibana's field format
number, percent, bytes, bits pattern, locale?, alwaysShowSign?, suffix? Numeral.js pattern, in Kibana's number locale (format:number:defaultLocale, en when absent)
duration input, output, decimals?, showSuffix?, useShortSuffix?, includeSpaceWithSuffix?, suffix? input is the stored unit; output a unit, humanize or humanizePrecise
date pattern, timeZone Moment.js pattern in an IANA time zone (dateFormat:tz, resolved)
text — The value as a string 
type ColorValue =
  | { light: string; dark: string }
  | { token: ChromeToken }
  | { palette: 'categorical'; index: number };
  1. data colors: always concrete
  2. chrome only
  3. charts authored with no palette of their own

Colors are #rgb, #rrggbb or #rrggbbaa. ChromeToken is one of text, textSubdued, axis, gridLine, background and border. The scheme is always chosen explicitly when a node is drawn, so a renderer never relies on CSS light-dark() alone.

colors.byKey maps a series or category key to a color; each chart states what its keys are (metric by its breakdown cell, xyChart by series), and each key part is escaped so a missing cell (\null) never collides with the string "null". colors.bands colors by value range: from is inclusive, to exclusive, and an absent bound is open. Each band with both bounds has from below to, and bands ascend without overlapping.

source: {
  kind: 'kibana';
  kibanaVersion: string;
  materializer: string;
  materializerVersion: number;
  spaceId?: string;
  savedObjectType?: string;
  savedObjectId?: string;
  panelId?: string;
  timeRange?: { from: string; to: string };
  capturedAt: string;
}
  1. such as 'lens'
  2. absolute ISO 8601
  3. ISO 8601

A node is a static snapshot. A host shows when it was captured, and refreshes it by materializing again from its provenance.

{ path, kind: 'dropped' | 'approximated' | 'prerendered', note }[]: what the source had that the node drops or approximates. Studio and hosts can show it, and tests can pin it.