king-crimson

A library that provides classes for managing sequential data.

Installation

npm install king-crimson

Usage

The following two management classes are provided.

• DateTimeDataManager: Manage data with datetime information.
• IntervalDataManager: Manages data with interval information.

DateTimeDataManager

import { DateTimeDataManager } from "king-crimson";
import { DateTime, Duration, Interval } from "luxon";
import queryString from "query-string";

// Event data to manage
interface MyEventData {
  timestamp: number;
  event: string;
}

// Create an async function to call API
const fetchData = async (since: number, until: number, signal: AbortSignal) => {
  const query = queryString.stringify({ since, until });
  const url = `https://example.com/api/data?${query}`;
  const res = await fetch(uri, { signal });
  const data = await res.json();
  return data;
};

// Create instance
const ddm = new DateTimeDataManager<MyEventData>({
  fetchFn(period: Interval) {
    const controller = new AbortController();
    const signal = controller.signal;
    const since = period.start.toMillis();
    const until = period.end.toMillis();
    return {
      promise: fetchData(since, until, signal),
      cancel() {
        controller.abort();
      }
    };
  },
  itemKey(item: MyEventData) {
    return item.timestamp;
  }
});

// Execute fetch
const datetime = DateTime.local();
ddm.fetch(datetime);

// Cancel fetch
ddm.cansel();

// Search data
const interval = datetime.before(Duration.fromObject({ hour: 1 }));
const data = ddm.searchBetween(interval);

Config

| Property | Type | Description | | -------- | --------------------------------------------------------------------- | ----------------------------------------------------------- | | fetchFn | (period: Interval) => { promise: Promise<T[]>, cancel: () => void } | Methods that request data and methods that cancel requests. | | itemKey | (item: T) => any | Key value of AVL tree. |

Options

| Property | Type | Default | Description | | -------------------- | ------------------------------------------------------------------------------------------ | -------------------------------------- | ------------------------------------------------------------------------- | | fetchDuration | Duration | Duration.fromObject({ hour: 24 }) | Duration for making data requests in batch. | | requestDurationLimit | Duration | Duration.fromObject({ minute: 180 }) | Duration limit for one data request. | | updateInterceptor | ((payload: { items: T[], period: Interval }) => { items: T[], period: Interval }) | null | null | Interceptor that transforms the payload before handling the update event. |

IntervalDataManager

import { IntervalDataManager } from "king-crimson";
import { DateTime, Duration, Interval } from "luxon";
import queryString from "query-string";

// Event data to manage
interface MyEventData {
  timestamp: number;
  duration: number;
  event: string;
}

// Create an async function to call API
const fetchData = async (since: number, until: number, signal: AbortSignal) => {
  const query = queryString.stringify({ since, until });
  const url = `https://example.com/api/data?${query}`;
  const res = await fetch(uri, { signal });
  const data = await res.json();
  return data;
};

// Create instance
const idm = new IntervalDataManager<MyEventData>({
  fetchFn(period: Interval) {
    const controller = new AbortController();
    const signal = controller.signal;
    const since = period.start.toMillis();
    const until = period.end.toMillis();
    return {
      promise: fetchData(since, until, signal),
      cancel() {
        controller.abort();
      }
    };
  },
  itemKey(item: MyEventData) {
    return item.timestamp;
  },
  itemTimestamp(item: MyEventData) {
    return item.timestamp;
  },
  itemDuration(item: MyEventData) {
    return item.duration;
  }
});

// Execute fetch
const datetime = DateTime.local();
idm.fetch(datetime);

// Cancel fetch
idm.cansel();

// Search data
const interval = datetime.before(Duration.fromObject({ hour: 1 }));
let data = idm.searchBetween(interval);

// Search for data that includes a specified datetime
data = searchOn(datetime);

Config

| Property | Type | Description | | ------------- | --------------------------------------------------------------------- | ---------------------------------------------------------------------- | | fetchFn | (period: Interval) => { promise: Promise<T[]>, cancel: () => void } | Methods that request data and methods that cancel requests. | | itemKey | (item: T) => any | Key value of AVL tree. | | itemTimestamp | (item: T) => number | Method that returns the timestamp of data in Unixtime in milliseconds. | | itemDuration | (item: T) => number | Method that returns duration of data in milliseconds. |

Options

| Property | Type | Default | Description | | -------------------- | ------------------------------------------------------------------------------------------ | -------------------------------------- | ------------------------------------------------------------------------- | | fetchDuration | Duration | Duration.fromObject({ hour: 24 }) | Duration for making data requests in batch. | | requestDurationLimit | Duration | Duration.fromObject({ minute: 180 }) | Duration limit for one data request. | | updateInterceptor | ((payload: { items: T[], period: Interval }) => { items: T[], period: Interval }) | null | null | Interceptor that transforms the payload before handling the update event. |

Event

Both classes emit the following events:

| Event | Payload | Description | | ------ | ---------------------------------- | --------------------------------------------------------------------------------------------- | | update | { items: T[], period: Interval } | When each data fetch is completed, the acquired data and the acquisition period are notified. |