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OHZI Components

RequestManager

  • Sends JSON HTTP requests from a Web Worker, so fetching and body parsing stay off the main thread.
  • Singleton. import { RequestManager } from 'ohzi-components' gives you the instance, so don't call new.

Methods

  • init(browser): Initialize component. Creates the worker.

    • browser: Browser from ohzi-core. Call it after Browser.init(). Safari requests use cache: 'no-cache', other browsers use 'default'.

  • get(url, callback, error_callback): Sends a GET request.

  • post(url, data, callback, error_callback): Sends a POST request with data as the JSON body.

  • put(url, data, callback, error_callback): Sends a PUT request with data as the JSON body.

  • delete(url, data, callback, error_callback): Sends a DELETE request with data as the JSON body.

  • __request({ url, method, data, headers, with_data, callback, error_callback }): The call behind the four methods above. (private)

    • headers: Extra headers, merged over Content-Type: application/json.
    • with_data: false skips reading the body, so callback gets the status only. Default true.

Callbacks

Both callbacks receive (status, data):

  • callback: The response arrived and its status isn't 4xx. data is the parsed JSON body, or the raw text when the body isn't JSON.
  • error_callback:
    • 4xx response: status is the response status and data is the parsed body.
    • Network failure: status is 0 and data is the error message.

A missing callback logs Request not handlered (or Error not handlered).

Request options

Every request uses mode: 'cors', credentials: 'same-origin', redirect: 'follow' and Content-Type: application/json, and sends JSON.stringify(data) as the body.

Example

import { Browser } from 'ohzi-core';
import { RequestManager } from 'ohzi-components';

RequestManager.init(Browser);

RequestManager.get('/api/scores',
  (status, data) =>
  {
    console.log(status, data);
  },
  (status, error) =>
  {
    console.warn('Could not load scores', status, error);
  });

RequestManager.post('/api/scores', { name: 'ohzi', score: 10 }, on_saved, on_failed);

Notes

  • 5xx responses go to callback, not error_callback. Check status in callback.
  • Callbacks are stored by URL. If two requests to the same URL are in flight, both responses go to the callbacks of the last one.
  • A relative URL like api/scores resolves against the worker script, not the page. Use root-relative (/api/scores) or absolute URLs.
  • There is no timeout or abort.
  • The worker is loaded from ./RequestWorker.ts, next to the module. That works when the app bundles ohzi-components from src/, as the boilerplate's Vite alias does. The published build/index.module.mjs keeps that URL but doesn't ship the worker file.