✨ Add PostHog Node (#1440)

* ✨ PostHog Node

* ⚡ Minor improvements to PostHog Node

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

packages/nodes-base/nodes/PostHog/PostHog.node.ts

@@ -0,0 +1,248 @@
+import {
+	IExecuteFunctions,
+} from 'n8n-core';
+
+import {
+	IDataObject,
+	INodeExecutionData,
+	INodeType,
+	INodeTypeDescription,
+} from 'n8n-workflow';
+
+import {
+	IAlias,
+	IEvent,
+	IIdentity,
+	ITrack,
+	posthogApiRequest,
+} from './GenericFunctions';
+
+import {
+	aliasFields,
+	aliasOperations,
+} from './AliasDescription';
+
+import {
+	eventFields,
+	eventOperations,
+} from './EventDescription';
+
+import {
+	trackFields,
+	trackOperations,
+} from './TrackDescription';
+
+import {
+	identityFields,
+	identityOperations,
+} from './IdentityDescription';
+
+import * as moment from 'moment-timezone';
+
+export class PostHog implements INodeType {
+	description: INodeTypeDescription = {
+		displayName: 'PostHog',
+		name: 'postHog',
+		icon: 'file:postHog.svg',
+		group: ['input'],
+		version: 1,
+		subtitle: '={{$parameter["operation"] + ": " + $parameter["resource"]}}',
+		description: 'Consume PostHog API.',
+		defaults: {
+			name: 'PostHog',
+			color: '#000000',
+		},
+		inputs: ['main'],
+		outputs: ['main'],
+		credentials: [
+			{
+				name: 'postHogApi',
+				required: true,
+			},
+		],
+		properties: [
+			{
+				displayName: 'Resource',
+				name: 'resource',
+				type: 'options',
+				options: [
+					{
+						name: 'Alias',
+						value: 'alias',
+					},
+					{
+						name: 'Event',
+						value: 'event',
+					},
+					{
+						name: 'Identity',
+						value: 'identity',
+					},
+					{
+						name: 'Track',
+						value: 'track',
+					},
+				],
+				default: 'event',
+				description: 'The resource to operate on.',
+			},
+			...aliasOperations,
+			...aliasFields,
+			...eventOperations,
+			...eventFields,
+			...identityOperations,
+			...identityFields,
+			...trackOperations,
+			...trackFields,
+		],
+	};
+
+	async execute(this: IExecuteFunctions): Promise<INodeExecutionData[][]> {
+		const items = this.getInputData();
+		const returnData: IDataObject[] = [];
+		const length = (items.length as unknown) as number;
+		const qs: IDataObject = {};
+		let responseData;
+		const resource = this.getNodeParameter('resource', 0) as string;
+		const operation = this.getNodeParameter('operation', 0) as string;
+
+		if (resource === 'alias') {
+			if (operation === 'create') {
+				for (let i = 0; i < length; i++) {
+					const distinctId = this.getNodeParameter('distinctId', i) as string;
+
+					const alias = this.getNodeParameter('alias', i) as string;
+
+					const additionalFields = this.getNodeParameter('additionalFields', i) as IDataObject;
+
+					const context = (additionalFields.contextUi as IDataObject || {}).contextValues as IDataObject[] || [];
+
+					const event: IAlias = {
+						type: 'alias',
+						event: '$create_alias',
+						context: context.reduce((obj, value) => Object.assign(obj, { [`${value.key}`]: value.value }), {}),
+						properties: {
+							distinct_id: distinctId,
+							alias,
+						},
+					};
+
+					Object.assign(event, additionalFields);
+
+					if (additionalFields.timestamp) {
+						additionalFields.timestamp = moment(additionalFields.timestamp as string).toISOString();
+					}
+
+					responseData = await posthogApiRequest.call(this, 'POST', '/batch', event);
+
+					returnData.push(responseData);
+				}
+			}
+		}
+
+		if (resource === 'event') {
+			if (operation === 'create') {
+				const events: IEvent[] = [];
+				for (let i = 0; i < length; i++) {
+					const eventName = this.getNodeParameter('eventName', i) as string;
+
+					const distinctId = this.getNodeParameter('distinctId', i) as string;
+
+					const additionalFields = this.getNodeParameter('additionalFields', i) as IDataObject;
+
+					const properties = (additionalFields.propertiesUi as IDataObject || {}).propertyValues as IDataObject[] || [];
+
+					const event: IEvent = {
+						event: eventName,
+						properties: properties.reduce((obj, value) => Object.assign(obj, { [`${value.key}`]: value.value }), {}),
+					};
+
+					event.properties['distinct_id'] = distinctId;
+
+					Object.assign(event, additionalFields);
+
+					if (additionalFields.timestamp) {
+						additionalFields.timestamp = moment(additionalFields.timestamp as string).toISOString();
+					}
+					//@ts-ignore
+					delete event.propertiesUi;
+
+					events.push(event);
+				}
+
+				responseData = await posthogApiRequest.call(this, 'POST', '/capture', { batch: events });
+
+				returnData.push(responseData);
+			}
+		}
+
+		if (resource === 'identity') {
+			if (operation === 'create') {
+				for (let i = 0; i < length; i++) {
+					const distinctId = this.getNodeParameter('distinctId', i) as string;
+
+					const additionalFields = this.getNodeParameter('additionalFields', i) as IDataObject;
+
+					const properties = (additionalFields.propertiesUi as IDataObject || {}).propertyValues as IDataObject[] || [];
+
+					const event: IIdentity = {
+						event: '$identify',
+						properties: properties.reduce((obj, value) => Object.assign(obj, { [`${value.key}`]: value.value }), {}),
+						distinct_id: distinctId,
+					};
+
+					Object.assign(event, additionalFields);
+
+					if (additionalFields.timestamp) {
+						additionalFields.timestamp = moment(additionalFields.timestamp as string).toISOString();
+					}
+					//@ts-ignore
+					delete event.propertiesUi;
+
+					responseData = await posthogApiRequest.call(this, 'POST', '/batch', event);
+
+					returnData.push(responseData);
+				}
+			}
+		}
+
+		if (resource === 'track') {
+			if (operation === 'page' || operation === 'screen') {
+				for (let i = 0; i < length; i++) {
+					const distinctId = this.getNodeParameter('distinctId', i) as string;
+
+					const name = this.getNodeParameter('name', i) as string;
+
+					const additionalFields = this.getNodeParameter('additionalFields', i) as IDataObject;
+
+					const context = (additionalFields.contextUi as IDataObject || {}).contextValues as IDataObject[] || [];
+
+					const properties = (additionalFields.propertiesUi as IDataObject || {}).propertyValues as IDataObject[] || [];
+
+					const event: ITrack = {
+						name,
+						type: operation,
+						event: `$${operation}`,
+						context: context.reduce((obj, value) => Object.assign(obj, { [`${value.key}`]: value.value }), {}),
+						distinct_id: distinctId,
+						properties: properties.reduce((obj, value) => Object.assign(obj, { [`${value.key}`]: value.value }), {}),
+					};
+
+					Object.assign(event, additionalFields);
+
+					if (additionalFields.timestamp) {
+						additionalFields.timestamp = moment(additionalFields.timestamp as string).toISOString();
+					}
+					//@ts-ignore
+					delete event.propertiesUi;
+
+					responseData = await posthogApiRequest.call(this, 'POST', '/batch', event);
+
+					returnData.push(responseData);
+				}
+			}
+		}
+
+		return [this.helpers.returnJsonArray(returnData)];
+	}
+}