alarm-status-widget.ts

import { IAlarm } from './alarm-base';
import { AlarmState } from './alarm-rule';
import { ConcreteWidget } from './widget';

/**
 * The sort possibilities for AlarmStatusWidgets
 */
export enum AlarmStatusWidgetSortBy {

  /**
   * Choose DEFAULT to sort them in alphabetical order by alarm name.
   */
  DEFAULT = 'default',

  /**
   * Choose STATE_UPDATED_TIMESTAMP to sort them first by alarm state, with alarms in ALARM state first,
   * INSUFFICIENT_DATA alarms next, and OK alarms last.
   * Within each group, the alarms are sorted by when they last changed state, with more recent state changes listed first.
   */
  STATE_UPDATED_TIMESTAMP = 'stateUpdatedTimestamp',

  /**
   * Choose TIMESTAMP to sort them by the time when the alarms most recently changed state,
   * no matter the current alarm state.
   * The alarm that changed state most recently is listed first.
   */
  TIMESTAMP = 'timestamp',
}

/**
 * Properties for an Alarm Status Widget
 */
export interface AlarmStatusWidgetProps {
  /**
   * CloudWatch Alarms to show in widget
   */
  readonly alarms: IAlarm[];
  /**
   * The title of the widget
   *
   * @default 'Alarm Status'
   */
  readonly title?: string;
  /**
   * Width of the widget, in a grid of 24 units wide
   *
   * @default 6
   */
  readonly width?: number;
  /**
   * Height of the widget
   *
   * @default 3
   */
  readonly height?: number;

  /**
   * Specifies how to sort the alarms in the widget.
   *
   * @default - alphabetical order
   */
  readonly sortBy?: AlarmStatusWidgetSortBy;

  /**
   * Use this field to filter the list of alarms displayed in the widget to only those alarms currently in the specified states.
   * You can specify one or more alarm states in the value for this field.
   * The alarm states that you can specify are ALARM, INSUFFICIENT_DATA, and OK.
   *
   * If you omit this field or specify an empty array, all the alarms specifed in alarms are displayed.
   *
   * @default -  all the alarms specified in alarms are displayed.
   */
  readonly states?: AlarmState[];
}

/**
 * A dashboard widget that displays alarms in a grid view
 */
export class AlarmStatusWidget extends ConcreteWidget {
  private readonly props: AlarmStatusWidgetProps;

  constructor(props: AlarmStatusWidgetProps) {
    super(props.width || 6, props.height || 3);
    this.props = props;
  }

  public position(x: number, y: number): void {
    this.x = x;
    this.y = y;
  }

  public toJson(): any[] {
    return [
      {
        type: 'alarm',
        width: this.width,
        height: this.height,
        x: this.x,
        y: this.y,
        properties: {
          title: this.props.title ? this.props.title : 'Alarm Status',
          alarms: this.props.alarms.map((alarm) => alarm.alarmArn),
          states: this.props.states,
          sortBy: this.props.sortBy,
        },
      },
    ];
  }
}