⚡ Fixed build and made some smaller changes

packages/nodes-base/nodes/PayPal/GenericFunctions.ts

@@ -0,0 +1,119 @@
+import { OptionsWithUri } from 'request';
+
+import {
+	IExecuteFunctions,
+	IHookFunctions,
+	ILoadOptionsFunctions,
+	IExecuteSingleFunctions,
+	BINARY_ENCODING
+} from 'n8n-core';
+
+import {
+	IDataObject,
+} from 'n8n-workflow';
+
+export async function payPalApiRequest(this: IHookFunctions | IExecuteFunctions | IExecuteSingleFunctions | ILoadOptionsFunctions, endpoint: string, method: string, body: any = {}, query?: IDataObject, uri?: string): Promise<any> { // tslint:disable-line:no-any
+	const credentials = this.getCredentials('payPalApi');
+	const env = getEnviroment(credentials!.env as string);
+	const tokenInfo =  await getAccessToken.call(this);
+	const headerWithAuthentication = Object.assign({ },
+		{ Authorization: `Bearer ${tokenInfo.access_token}`, 'Content-Type': 'application/json' });
+	const options = {
+		headers: headerWithAuthentication,
+		method,
+		qs: query || {},
+		uri: uri || `${env}/v1${endpoint}`,
+		body,
+		json: true
+	};
+	try {
+		return await this.helpers.request!(options);
+	} catch (error) {
+		const errorMessage = error.response.body.message || error.response.body.Message;
+
+		if (errorMessage !== undefined) {
+			throw errorMessage;
+		}
+		throw error.response.body;
+	}
+}
+
+function getEnviroment(env: string): string {
+	// @ts-ignore
+	return {
+		'sanbox': 'https://api.sandbox.paypal.com',
+		'live': 'https://api.paypal.com'
+	}[env];
+}
+
+async function getAccessToken(this: IHookFunctions | IExecuteFunctions | IExecuteSingleFunctions | ILoadOptionsFunctions): Promise<any> { // tslint:disable-line:no-any
+	const credentials = this.getCredentials('payPalApi');
+	if (credentials === undefined) {
+		throw new Error('No credentials got returned!');
+	}
+	const env = getEnviroment(credentials!.env as string);
+	const data = Buffer.from(`${credentials!.clientId}:${credentials!.secret}`).toString(BINARY_ENCODING);
+	const headerWithAuthentication = Object.assign({},
+		{ Authorization: `Basic ${data}`, 'Content-Type': 'application/x-www-form-urlencoded' });
+		const options: OptionsWithUri = {
+			headers: headerWithAuthentication,
+			method: 'POST',
+			form: {
+				grant_type: 'client_credentials',
+			},
+			uri: `${env}/v1/oauth2/token`,
+			json: true
+		};
+	try {
+		return await this.helpers.request!(options);
+	} catch (error) {
+		const errorMessage = error.response.body.message || error.response.body.Message;
+
+		if (errorMessage !== undefined) {
+			throw errorMessage;
+		}
+		throw error.response.body;
+	}
+}
+
+/**
+ * Make an API request to paginated paypal endpoint
+ * and return all results
+ */
+export async function payPalApiRequestAllItems(this: IHookFunctions | IExecuteFunctions | IExecuteSingleFunctions | ILoadOptionsFunctions, propertyName: string, endpoint: string, method: string, body: any = {}, query?: IDataObject, uri?: string): Promise<any> { // tslint:disable-line:no-any
+
+	const returnData: IDataObject[] = [];
+
+	let responseData;
+
+	query!.page_size = 1000;
+
+	do {
+		responseData = await payPalApiRequest.call(this, endpoint, method, body, query, uri);
+		uri = getNext(responseData.links);
+		returnData.push.apply(returnData, responseData[propertyName]);
+	} while (
+		getNext(responseData.links) !== undefined
+	);
+
+	return returnData;
+}
+
+function getNext(links: IDataObject[]): string | undefined {
+	for (const link of links) {
+		if (link.rel === 'next') {
+			return link.href as string;
+		}
+	}
+	return undefined;
+}
+
+export function validateJSON(json: string | undefined): any { // tslint:disable-line:no-any
+	let result;
+	try {
+		result = JSON.parse(json!);
+	} catch (exception) {
+		result = '';
+	}
+	return result;
+}