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

import { OptionsWithUri } from 'request';

import { IExecuteFunctions, IExecuteSingleFunctions, ILoadOptionsFunctions } from 'n8n-core';

import {
	// ICredentialDataDecryptedObject,
	ICredentialTestFunctions,
	IDataObject,
	INodeProperties,
	NodeApiError,
} from 'n8n-workflow';

import moment from 'moment-timezone';

import jwt from 'jsonwebtoken';

interface IGoogleAuthCredentials {
	delegatedEmail?: string;
	email: string;
	inpersonate: boolean;
	privateKey: string;
}

export async function googleApiRequest(
	this: IExecuteFunctions | IExecuteSingleFunctions | ILoadOptionsFunctions,
	method: string,
	resource: string,

	body: any = {},
	qs: IDataObject = {},
	uri?: string,
	noCredentials = false,
	encoding?: null | undefined,
): Promise<any> {
	const options: OptionsWithUri = {
		headers: {
			'Content-Type': 'application/json',
		},
		method,
		body,
		qs,
		uri: uri || `https://chat.googleapis.com${resource}`,
		json: true,
	};

	if (Object.keys(body).length === 0) {
		delete options.body;
	}

	if (encoding === null) {
		options.encoding = null;
	}

	let responseData: IDataObject | undefined;
	try {
		if (noCredentials) {
			//@ts-ignore
			responseData = await this.helpers.request(options);
		} else {
			const credentials = await this.getCredentials('googleApi');

			const { access_token } = await getAccessToken.call(
				this,
				credentials as unknown as IGoogleAuthCredentials,
			);
			options.headers!.Authorization = `Bearer ${access_token}`;
			//@ts-ignore
			responseData = await this.helpers.request(options);
		}
	} catch (error) {
		if (error.code === 'ERR_OSSL_PEM_NO_START_LINE') {
			error.statusCode = '401';
		}

		throw new NodeApiError(this.getNode(), error);
	}
	if (Object.keys(responseData as IDataObject).length !== 0) {
		return responseData;
	} else {
		return { success: true };
	}
}

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

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

	let responseData;
	query.pageSize = 100;

	do {
		responseData = await googleApiRequest.call(this, method, endpoint, body, query);
		query.pageToken = responseData.nextPageToken;
		returnData.push.apply(returnData, responseData[propertyName]);
	} while (responseData.nextPageToken !== undefined && responseData.nextPageToken !== '');

	return returnData;
}

export async function getAccessToken(
	this:
		| IExecuteFunctions
		| IExecuteSingleFunctions
		| ILoadOptionsFunctions
		| ICredentialTestFunctions,
	credentials: IGoogleAuthCredentials,
): Promise<IDataObject> {
	//https://developers.google.com/identity/protocols/oauth2/service-account#httprest

	const scopes = ['https://www.googleapis.com/auth/chat.bot'];

	const now = moment().unix();

	credentials.email = credentials.email.trim();
	const privateKey = credentials.privateKey.replace(/\\n/g, '\n').trim();

	const signature = jwt.sign(
		{
			iss: credentials.email,
			sub: credentials.delegatedEmail || credentials.email,
			scope: scopes.join(' '),
			aud: `https://oauth2.googleapis.com/token`,
			iat: now,
			exp: now + 3600,
		},
		privateKey,
		{
			algorithm: 'RS256',
			header: {
				kid: privateKey,
				typ: 'JWT',
				alg: 'RS256',
			},
		},
	);

	const options: OptionsWithUri = {
		headers: {
			'Content-Type': 'application/x-www-form-urlencoded',
		},
		method: 'POST',
		form: {
			grant_type: 'urn:ietf:params:oauth:grant-type:jwt-bearer',
			assertion: signature,
		},
		uri: 'https://oauth2.googleapis.com/token',
		json: true,
	};

	return this.helpers.request!(options);
}

export function validateJSON(json: string | undefined): any {
	let result;
	try {
		result = JSON.parse(json!);
	} catch (exception) {
		result = undefined;
	}
	return result;
}

export function getPagingParameters(resource: string, operation = 'getAll') {
	const pagingParameters: INodeProperties[] = [
		{
			displayName: 'Return All',
			name: 'returnAll',
			type: 'boolean',
			displayOptions: {
				show: {
					resource: [resource],
					operation: [operation],
				},
			},
			default: false,
			description: 'Whether to return all results or only up to a given limit',
		},
		{
			displayName: 'Limit',
			name: 'limit',
			type: 'number',
			typeOptions: {
				maxValue: 1000,
			},
			displayOptions: {
				show: {
					resource: [resource],
					operation: [operation],
					returnAll: [false],
				},
			},
			default: 100,
			description: 'Max number of results to return',
		},
	];
	return pagingParameters;
}