import { OptionsWithUri } from 'request'; import { IExecuteFunctions, ILoadOptionsFunctions } from 'n8n-core'; import { IDataObject, 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 | ILoadOptionsFunctions, method: string, resource: string, body: IDataObject = {}, qs: IDataObject = {}, ) { const authenticationMethod = this.getNodeParameter( 'authentication', 0, 'serviceAccount', ) as string; const options: OptionsWithUri & { headers: IDataObject } = { headers: { 'Content-Type': 'application/json', }, method, body, qs, uri: `https://slides.googleapis.com/v1${resource}`, json: true, }; if (!Object.keys(body).length) { delete options.body; } if (!Object.keys(qs).length) { delete options.qs; } try { if (authenticationMethod === 'serviceAccount') { const credentials = await this.getCredentials('googleApi'); const { access_token } = await getAccessToken.call( this, credentials as unknown as IGoogleAuthCredentials, ); options.headers.Authorization = `Bearer ${access_token}`; return await this.helpers.request!(options); } else { return await this.helpers.requestOAuth2!.call(this, 'googleSlidesOAuth2Api', options); } } catch (error) { if (error.code === 'ERR_OSSL_PEM_NO_START_LINE') { error.statusCode = '401'; } throw new NodeApiError(this.getNode(), error); } } async function getAccessToken( this: IExecuteFunctions | ILoadOptionsFunctions, credentials: IGoogleAuthCredentials, ) { // https://developers.google.com/identity/protocols/oauth2/service-account#httprest const scopes = [ 'https://www.googleapis.com/auth/drive.file', 'https://www.googleapis.com/auth/presentations', ]; 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.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); }