n8n/packages/nodes-base/nodes/Google/Books/GenericFunctions.ts

import type {
	IExecuteFunctions,
	ILoadOptionsFunctions,
	IDataObject,
	JsonObject,
	IHttpRequestMethods,
	IRequestOptions,
} from 'n8n-workflow';
import { NodeApiError } from 'n8n-workflow';
import { getGoogleAccessToken } from '../GenericFunctions';

export async function googleApiRequest(
	this: IExecuteFunctions | ILoadOptionsFunctions,
	method: IHttpRequestMethods,
	resource: string,
	body: any = {},
	qs: IDataObject = {},
	uri?: string,
	headers: IDataObject = {},
): Promise<any> {
	const authenticationMethod = this.getNodeParameter(
		'authentication',
		0,
		'serviceAccount',
	) as string;
	const options: IRequestOptions = {
		headers: {
			'Content-Type': 'application/json',
		},
		method,
		body,
		qs,
		uri: uri || `https://www.googleapis.com/books/${resource}`,
		json: true,
	};
	try {
		if (Object.keys(headers).length !== 0) {
			options.headers = Object.assign({}, options.headers, headers);
		}
		if (Object.keys(body as IDataObject).length === 0) {
			delete options.body;
		}

		if (authenticationMethod === 'serviceAccount') {
			const credentials = (await this.getCredentials('googleApi')) as {
				email: string;
				privateKey: string;
			};

			const { access_token } = await getGoogleAccessToken.call(this, credentials, 'books');

			options.headers!.Authorization = `Bearer ${access_token}`;

			return await this.helpers.request(options);
		} else {
			return await this.helpers.requestOAuth2.call(this, 'googleBooksOAuth2Api', options);
		}
	} catch (error) {
		if (error.code === 'ERR_OSSL_PEM_NO_START_LINE') {
			error.statusCode = '401';
		}

		throw new NodeApiError(this.getNode(), error as JsonObject);
	}
}

export async function googleApiRequestAllItems(
	this: IExecuteFunctions | ILoadOptionsFunctions,
	propertyName: string,
	method: IHttpRequestMethods,
	endpoint: string,

	body: any = {},
	query: IDataObject = {},
): Promise<any> {
	const returnData: IDataObject[] = [];

	let responseData;
	query.maxResults = 40;

	do {
		responseData = await googleApiRequest.call(this, method, endpoint, body, query);
		returnData.push.apply(returnData, (responseData[propertyName] as IDataObject[]) || []);
	} while (returnData.length < responseData.totalItems);

	return returnData;
}