AbstractWebMessaging.ts

import { DesktopAgentDetails, WebDesktopAgentType, GetAgentParams } from '@kite9/fdc3-standard';
import { RegisterableListener, AbstractMessaging } from '@kite9/fdc3-agent-proxy';
import {
  AppRequestMessage,
  WebConnectionProtocol5ValidateAppIdentitySuccessResponse,
} from '@kite9/fdc3-schema/generated/api/BrowserTypes';

type RequestMetadata = AppRequestMessage['meta'];

export const DESKTOP_AGENT_SESSION_STORAGE_DETAILS_KEY = 'fdc3-desktop-agent-details';

/**
 * Version of Messaging which is able to store details in the SessionState (i.e. works on the web)
 */
export abstract class AbstractWebMessaging extends AbstractMessaging {
  constructor(options: GetAgentParams, connectionAttemptUuid: string, actualUrl: string, timeout?: number) {
    super(options, connectionAttemptUuid, actualUrl, timeout);
  }

  abstract createUUID(): string;
  abstract post(message: object): Promise<void>;

  abstract register(l: RegisterableListener): void;
  abstract unregister(id: string): void;

  abstract createMeta(): RequestMetadata;

  /**
   * Note that we also key by the window name as well, in case multiple iframes are using the same session storage.
   */
  private sessionKey(): string {
    const windowName = globalThis.window.name;
    const keyName = windowName
      ? DESKTOP_AGENT_SESSION_STORAGE_DETAILS_KEY + '-' + windowName
      : DESKTOP_AGENT_SESSION_STORAGE_DETAILS_KEY;
    return keyName;
  }

  /**
   * Used to allow session-reconnection
   */
  storeInstanceUuid(vr: WebConnectionProtocol5ValidateAppIdentitySuccessResponse) {
    const details: DesktopAgentDetails = {
      agentType: WebDesktopAgentType.ProxyParent,
      instanceUuid: vr.payload.instanceUuid,
      appId: vr.payload.appId,
      instanceId: vr.payload.instanceId,
    };

    globalThis.sessionStorage.setItem(this.sessionKey(), JSON.stringify(details));
  }

  /**
   * Stores the instanceUuid in session storage in case session needs reconnecting.
   */
  retrieveInstanceUuid(): string | undefined {
    const detailsStr = globalThis.sessionStorage.getItem(this.sessionKey());

    if (detailsStr) {
      const details = JSON.parse(detailsStr) as DesktopAgentDetails;
      if (details.agentType == WebDesktopAgentType.ProxyParent) {
        return details.instanceUuid;
      }
    }

    return undefined;
  }
}