Method updateClient

packages/service-worker/worker/src/driver.ts:550–577

(client: Client)

  }

  async updateClient(client: Client): Promise<boolean> {
    // Figure out which version the client is on. If it's not on the latest,
    // it needs to be moved.
    const existing = this.clientVersionMap.get(client.id);
    if (existing === this.latestHash) {
      // Nothing to do, this client is already on the latest version.
      return false;
    }

    // Switch the client over.
    let previous: Object | undefined = undefined;

    // Look up the application data associated with the existing version. If there
    // isn't any, fall back on using the hash.
    if (existing !== undefined) {
      const existingVersion = this.versions.get(existing)!;
      previous = this.mergeHashWithAppData(existingVersion.manifest, existing);
    }

    // Set the current version used by the client, and sync the mapping to disk.
    this.clientVersionMap.set(client.id, this.latestHash!);
    await this.sync();

    // Notify the client about this activation.
    const current = this.versions.get(this.latestHash!)!;

    return true;
  }

  private async handleFetch(event: FetchEvent): Promise<Response> {
    try {