n8n/packages/nodes-base/nodes/Postmark/PostmarkTrigger.node.ts

import {
	IHookFunctions,
	IWebhookFunctions,
} from 'n8n-core';

import {
	INodeType,
	INodeTypeDescription,
	IWebhookResponseData,
} from 'n8n-workflow';

import {
	convertTriggerObjectToStringArray,
	eventExists,
	postmarkApiRequest
} from './GenericFunctions';

export class PostmarkTrigger implements INodeType {
	description: INodeTypeDescription = {
		displayName: 'Postmark Trigger',
		name: 'postmarkTrigger',
		icon: 'file:postmark.png',
		group: ['trigger'],
		version: 1,
		description: 'Starts the workflow when Postmark events occur.',
		defaults: {
			name: 'Postmark Trigger',
			color: '#fedd00',
		},
		inputs: [],
		outputs: ['main'],
		credentials: [
			{
				name: 'postmarkApi',
				required: true,
			},
		],
		webhooks: [
			{
				name: 'default',
				httpMethod: 'POST',
				responseMode: 'onReceived',
				path: 'webhook',
			},
		],
		properties: [
			{
				displayName: 'Events',
				name: 'events',
				type: 'multiOptions',
				options: [
					{
						name: 'Bounce',
						value: 'bounce',
						description: 'Trigger on bounce.',
					},
					{
						name: 'Click',
						value: 'click',
						description: 'Trigger on click.',
					},
					{
						name: 'Delivery',
						value: 'delivery',
						description: 'Trigger on delivery.',
					},
					{
						name: 'Open',
						value: 'open',
						description: 'Trigger webhook on open.',
					},
					{
						name: 'Spam Complaint',
						value: 'spamComplaint',
						description: 'Trigger on spam complaint.',
					},
					{
						name: 'Subscription Change',
						value: 'subscriptionChange',
						description: 'Trigger on subscription change.',
					},
				],
				default: [],
				required: true,
				description: 'Webhook events that will be enabled for that endpoint.',
			},
			{
				displayName: 'First Open',
				name: 'firstOpen',
				description: 'Only fires on first open for event "Open".',
				type: 'boolean',
				default: false,
				displayOptions: {
					show: {
						events: [
							'open',
						],
					},
				},
			},
			{
				displayName: 'Include Content',
				name: 'includeContent',
				description: 'Includes message content for events "Bounce" and "Spam Complaint".',
				type: 'boolean',
				default: false,
				displayOptions: {
					show: {
						events: [
							'bounce',
							'spamComplaint',
						],
					},
				},
			},
		],

	};

	// @ts-ignore (because of request)
	webhookMethods = {
		default: {
			async checkExists(this: IHookFunctions): Promise<boolean> {
				const webhookData = this.getWorkflowStaticData('node');
				const webhookUrl = this.getNodeWebhookUrl('default');
				const events = this.getNodeParameter('events') as string[];

				if (events.includes('bounce') || events.includes('spamComplaint')) {
					if (this.getNodeParameter('includeContent') as boolean) {
						events.push('includeContent');
					}
				}

				if (events.includes('open')) {
					if (this.getNodeParameter('firstOpen') as boolean) {
						events.push('firstOpen');
					}
				}

				// Get all webhooks
				const endpoint = `/webhooks`;

				const responseData = await postmarkApiRequest.call(this, 'GET', endpoint, {});

				// No webhooks exist
				if (responseData.Webhooks.length === 0) {
					return false;
				}

				// If webhooks exist, check if any match current settings
				for (const webhook of responseData.Webhooks) {
					if (webhook.Url === webhookUrl && eventExists(events, convertTriggerObjectToStringArray(webhook))) {
						webhookData.webhookId = webhook.ID;
						// webhook identical to current settings. re-assign webhook id to found webhook.
						return true;
					}
				}

				return false;
			},
			async create(this: IHookFunctions): Promise<boolean> {
				const webhookUrl = this.getNodeWebhookUrl('default');

				const endpoint = `/webhooks`;

				// tslint:disable-next-line: no-any
				const body : any = {
					Url: webhookUrl,
					Triggers: {
						Open:{
							Enabled: false,
							PostFirstOpenOnly: false,
						},
						Click:{
							Enabled: false,
						},
						Delivery:{
							Enabled: false,
						},
						Bounce:{
							Enabled: false,
							IncludeContent: false,
						},
						SpamComplaint:{
							Enabled: false,
							IncludeContent: false,
						},
						SubscriptionChange: {
							Enabled: false,
						},
					},
				};

				const events = this.getNodeParameter('events') as string[];

				if (events.includes('open')) {
					body.Triggers.Open.Enabled = true;
					body.Triggers.Open.PostFirstOpenOnly = this.getNodeParameter('firstOpen') as boolean;
				}
				if (events.includes('click')) {
					body.Triggers.Click.Enabled = true;
				}
				if (events.includes('delivery')) {
					body.Triggers.Delivery.Enabled = true;
				}
				if (events.includes('bounce')) {
					body.Triggers.Bounce.Enabled = true;
					body.Triggers.Bounce.IncludeContent = this.getNodeParameter('includeContent') as boolean;
				}
				if (events.includes('spamComplaint')) {
					body.Triggers.SpamComplaint.Enabled = true;
					body.Triggers.SpamComplaint.IncludeContent = this.getNodeParameter('includeContent') as boolean;
				}
				if (events.includes('subscriptionChange')) {
					body.Triggers.SubscriptionChange.Enabled = true;
				}

				const responseData = await postmarkApiRequest.call(this, 'POST', endpoint, body);

				if (responseData.ID === undefined) {
					// Required data is missing so was not successful
					return false;
				}

				const webhookData = this.getWorkflowStaticData('node');
				webhookData.webhookId = responseData.ID as string;

				return true;
			},
			async delete(this: IHookFunctions): Promise<boolean> {
				const webhookData = this.getWorkflowStaticData('node');

				if (webhookData.webhookId !== undefined) {
					const endpoint = `/webhooks/${webhookData.webhookId}`;
					const body = {};

					try {
						await postmarkApiRequest.call(this, 'DELETE', endpoint, body);
					} catch (error) {
						return false;
					}

					// Remove from the static workflow data so that it is clear
					// that no webhooks are registred anymore
					delete webhookData.webhookId;
					delete webhookData.webhookEvents;
				}

				return true;
			},
		},
	};

	async webhook(this: IWebhookFunctions): Promise<IWebhookResponseData> {
		const req = this.getRequestObject();
		return {
			workflowData: [
				this.helpers.returnJsonArray(req.body),
			],
		};
	}
}