AshReports.Charts.Types.Behavior behaviour (ash_reports v0.1.0)

Behavior for chart type implementations.

All chart types must implement this behavior to ensure a consistent interface for chart generation. The behavior defines callbacks for building chart structures and validating data.

Implementing a Custom Chart

defmodule MyApp.CustomChart do
  @behaviour AshReports.Charts.Types.Behavior

  @impl true
  def build(data, config) do
    # Build chart using Contex or custom logic
    # Return Contex chart struct
  end

  @impl true
  def validate(data) do
    # Validate data format
    if valid_data?(data) do
      :ok
    else
      {:error, "Invalid data format"}
    end
  end
end

Required Callbacks

  • build/2 - Builds the chart structure from data and config
  • validate/1 - Validates the data format for this chart type

Summary

Callbacks

build(data, config)

Builds a chart structure from data and configuration.

validate(data)

Validates data format for the chart type.

Callbacks

build(data, config)

@callback build(data :: [map()], config :: map()) :: term()

Builds a chart structure from data and configuration.

Parameters

  • data - List of maps containing chart data
  • config - Type-specific config struct (e.g., BarChartConfig, LineChartConfig)

Returns

  • Chart structure (typically a Contex chart struct)
  • The structure will be passed to the renderer for SVG generation

Examples

def build(data, config) do
  dataset = Contex.Dataset.new(data)

  Contex.BarChart.new(dataset)
  |> Contex.BarChart.set_val_col_names(["value"])
  |> Contex.BarChart.colours(config.colours || [])
end

validate(data)

@callback validate(data :: term()) :: :ok | {:error, String.t()}

Validates data format for the chart type.

Parameters

  • data - List of maps containing chart data

Returns

  • :ok - Data is valid
  • {:error, reason} - Data is invalid

Examples

def validate(data) when is_list(data) do
  if Enum.all?(data, &Map.has_key?(&1, :value)) do
    :ok
  else
    {:error, "All data points must have a :value key"}
  end
end

def validate(_), do: {:error, "Data must be a list"}