✨ Add ServiceNow node (#1932)

* ✨ ServiceNow node

* Add Table Record resource & operations

* Add Incident resource & operations

* Add User resource & operations

* Add Business Service getAll operation

* Add Business Service, Department, Dictionary and Configuration Items resources

* Improvements

* Add continueOnFail

* Fix node display name

* Fix node credentials name

* Minor improvements

* Improvements

* Add load function for fields parameter

* Add load function for incident, user and table record fields

* Fix sending input function

* Enhance ServiceNow credentials

* Apply review changes & improvements

* Minor improvements

* Minor code enhancement

* Apply review changes

* ⚡ Small improvement

* Fix TableRecord update operation & add BusinessServices loading

* ⚡ Small improvement

* ⚡ Improve ServiceNow node

* ⚡ Fix one more description

Co-authored-by: ricardo <ricardoespinoza105@gmail.com>
Co-authored-by: Jan Oberhauser <jan.oberhauser@gmail.com>

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

@@ -0,0 +1,98 @@
+import {
+	OptionsWithUri
+} from 'request';
+
+import {
+	IExecuteFunctions,
+	ILoadOptionsFunctions,
+} from 'n8n-core';
+
+import {
+	IDataObject,
+	INodePropertyOptions,
+	NodeApiError,
+} from 'n8n-workflow';
+
+export async function serviceNowApiRequest(this: IExecuteFunctions | ILoadOptionsFunctions, method: string, resource: string, body: any = {}, qs: IDataObject = {}, uri?: string, option: IDataObject = {}): Promise<any> { // tslint:disable-line:no-any
+
+	const credentials = this.getCredentials('serviceNowOAuth2Api');
+
+	const options: OptionsWithUri = {
+		headers: {},
+		method,
+		qs,
+		body,
+		uri: uri || `https://${credentials?.subdomain}.service-now.com/api${resource}`,
+		json: true,
+	};
+	if (!Object.keys(body).length) {
+		delete options.body;
+	}
+
+	if (Object.keys(option).length !== 0) {
+		Object.assign(options, option);
+	}
+
+	if (options.qs.limit) {
+		delete options.qs.limit;
+	}
+
+	try {
+
+		return await this.helpers.requestOAuth2!.call(this, 'serviceNowOAuth2Api', options);
+
+	} catch (error) {
+		throw new NodeApiError(this.getNode(), error);
+	}
+}
+
+export async function serviceNowRequestAllItems(this: IExecuteFunctions | ILoadOptionsFunctions, method: string, resource: string, body: any = {}, query: IDataObject = {}): Promise<any> { // tslint:disable-line:no-any
+
+	const returnData: IDataObject[] = [];
+	let responseData;
+
+	const page = 100;
+
+	query.sysparm_limit = page;
+
+	responseData = await serviceNowApiRequest.call(this, method, resource, body, query, undefined, { resolveWithFullResponse: true });
+	returnData.push.apply(returnData, responseData.body.result);
+
+	const quantity = responseData.headers['x-total-count'];
+	const iterations = Math.round(quantity / page) + (quantity % page ? 1 : 0);
+
+	for (let iteration = 1; iteration < iterations; iteration++) {
+		query.sysparm_limit = page;
+		query.sysparm_offset = iteration * page;
+		responseData = await serviceNowApiRequest.call(this, method, resource, body, query, undefined, { resolveWithFullResponse: true });
+
+		returnData.push.apply(returnData, responseData.body.result);
+	}
+
+	return returnData;
+}
+
+
+export const mapEndpoint = (resource: string, operation: string) => {
+	const resourceEndpoint = new Map([
+		['tableRecord', 'sys_dictionary'],
+		['businessService', 'cmdb_ci_service'],
+		['configurationItems', 'cmdb_ci'],
+		['department', 'cmn_department'],
+		['dictionary', 'sys_dictionary'],
+		['incident', 'incident'],
+		['user', 'sys_user'],
+		['userGroup', 'sys_user_group'],
+		['userRole', 'sys_user_role'],
+	]);
+	return resourceEndpoint.get(resource);
+};
+
+export const sortData = (returnData: INodePropertyOptions[]): INodePropertyOptions[] => {
+	returnData.sort((a, b) => {
+		if (a.name < b.name) { return -1; }
+		if (a.name > b.name) { return 1; }
+		return 0;
+	});
+	return returnData;
+};