Add BaseManager class

[adamjmcgrath]

Changes

Adding a BaseManager class to DRY up the arguments parsing and rest client creation of all the Manager classes.

This should make it easier to customise the rest client and add other features in the future.

Before:

class SomeManager {
  constructor(options) {
    if (options === null || typeof options !== 'object') {
      throw new ArgumentError('Must provide client options');
    }

    if (options.baseUrl === null || options.baseUrl === undefined) {
      throw new ArgumentError('Must provide a base URL for the API');
    }

    if ('string' !== typeof options.baseUrl || options.baseUrl.length === 0) {
      throw new ArgumentError('The provided base URL is invalid');
    }

    const clientOptions = {
      errorFormatter: { message: 'message', name: 'error' },
      headers: options.headers,
      query: { repeatParams: false },
    };

    const auth0RestClient = new Auth0RestClient(
      `${options.baseUrl}/some/path/:id`,
      clientOptions,
      options.tokenProvider
    );
    this.resource = new RetryRestClient(auth0RestClient, options.retry);
  }
}

After:

class SomeManager extends BaseManager {
  constructor(options) {
    super(options);

    this.resource = this._getRestClient('/some/path/:id');
  }
}

[adamjmcgrath]

☝️ This is one of those cases where removing covered code drops the coverage percentage, even though you're not introducing uncovered code