feature(general): mailchimp api integration (#747)

* Initial Commit for Mailchimp API

- Adding in shared the Event Handler --> can be used by all apps
- Adding a specific next.js api for Mailchimp inside the Website

* Prettified Code!

* various small updates

* Add updates page to add files to Mailchimp

Add /updates page to add a user to Mailchimp

* Update for /updates page

* Prettified Code!

* wip

* cleanup

* wip

* wip

---------

Co-authored-by: brennerthomas <[email protected]>
Co-authored-by: Michael Kündig <[email protected]>

shared/locales/de/website-me.json

@@ -68,7 +68,8 @@
 		"country": "Land",
 		"language": "Kommunikationssprache",
 		"submit-button": "Kontaktangaben aktualisieren",
-		"user-updated-toast": "Deine Kontaktangaben wurden aktualisiert"
+		"user-updated-toast": "Deine Kontaktangaben wurden aktualisiert",
+		"newsletter-switch": "Ich möchte den Newsletter erhalten"
 	},
 	"security": {
 		"reset-password": {

shared/locales/de/website-newsletter.json

@@ -0,0 +1,22 @@
+{
+	"metadata": {
+		"title": "Datenschutzrichtlinie | Social Income"
+	},
+	"updates": {
+		"alert-title": "Social Income Newsletter",
+		"alert-description": "Melde dich an, um bei allen Thema rund um Social Income auf dem neusten Stand zu sein.",
+		"firstname": "Vorname",
+		"lastname": "Nachname",
+		"gender": "Geschlecht",
+		"email": "E-Mail",
+		"street": "Strasse",
+		"street-number": "Nummer",
+		"city": "Ort",
+		"zip": "PLZ",
+		"country": "Land",
+		"language": "Kommunikationssprache",
+		"submit-button": "Beim Newsletter anmelden",
+		"newsletter-updated-toast": "Du wurdest zum Newsletter hinzugefügt",
+		"newsletter-error-toast": "Du konntest leider nicht zum Newsletter hinzugefügt werden"
+	}
+}

shared/locales/en/website-me.json

@@ -68,7 +68,8 @@
 		"country": "Country",
 		"language": "Communication language",
 		"submit-button": "Update Personal Info",
-		"user-updated-toast": "Your personal info has been updated"
+		"user-updated-toast": "Your personal info has been updated",
+		"newsletter-switch": "I would like to receive the newsletter"
 	},
 	"security": {
 		"reset-password": {

shared/locales/en/website-newsletter.json

@@ -0,0 +1,22 @@
+{
+	"metadata": {
+		"title": "Datenschutzrichtlinie | Social Income"
+	},
+	"updates": {
+		"alert-title": "Social Income Newsletter",
+		"alert-description": "Sign up to stay up to date on all things of Social Income.",
+		"firstname": "First Name",
+		"lastname": "Last Name",
+		"gender": "Gender",
+		"email": "Email",
+		"street": "Street",
+		"street-number": "Number",
+		"city": "City",
+		"zip": "Zip",
+		"country": "Country",
+		"language": "Communication language",
+		"submit-button": "Subscribe to newsletter",
+		"newsletter-updated-toast": "You have been added to the newsletter",
+		"newsletter-error-toast": "We weren't able to add you to our newsletter"
+	}
+}

shared/package.json

@@ -10,13 +10,15 @@
 		"@jest/globals": "^29.7.0",
 		"@types/jest": "^29.5.10",
 		"@types/luxon": "^3.3.5",
+		"@types/mailchimp__mailchimp_marketing": "^3.0.17",
 		"@types/mjml": "^4.7.4",
 		"@types/nodemailer": "^6.4.14",
 		"firebase-functions-test": "^3.1.0",
 		"jest": "^29.7.0",
 		"ts-jest": "^29.1.1"
 	},
 	"dependencies": {
+		"@mailchimp/mailchimp_marketing": "^3.0.80",
 		"axios": "^1.6.2",
 		"firebase-admin": "^11.11.0",
 		"handlebars": "^4.7.8",

shared/src/mailchimp/MailchimpAPI.ts

@@ -0,0 +1,65 @@
+import mailchimp, { Status } from '@mailchimp/mailchimp_marketing';
+import { CountryCode } from '../types/country';
+
+export type MailchimpSubscriptionData = {
+	email: string;
+	status: Status;
+	language?: 'de' | 'en';
+	firstname?: string;
+	lastname?: string;
+	country?: CountryCode;
+};
+
+export class MailchimpAPI {
+	constructor(apiKey: string, server: string) {
+		mailchimp.setConfig({
+			apiKey: apiKey,
+			server: server,
+		});
+	}
+
+	getSubscriber = async (email: string, listId: string) => {
+		try {
+			return await mailchimp.lists.getListMember(listId, this.md5(email.toLowerCase()));
+		} catch (error) {
+			return null;
+		}
+	};
+
+	upsertSubscription = async (data: MailchimpSubscriptionData, listId: string) => {
+		const subscriber = await this.getSubscriber(data.email, listId);
+		if (subscriber === null) {
+			return this.createSubscription(data, listId);
+		} else {
+			await mailchimp.lists.updateListMember(listId, this.md5(data.email), {
+				email_address: data.email,
+				status: data.status,
+				merge_fields: {
+					FNAME: data.firstname ?? '',
+					LNAME: data.lastname ?? '',
+					COUNTRY: data.country ?? '',
+					LANGUAGE: data.language === 'de' ? 'German' : 'English',
+				},
+			});
+		}
+	};
+
+	createSubscription = async (data: MailchimpSubscriptionData, listId: string) => {
+		await mailchimp.lists.addListMember(listId, {
+			email_address: data.email,
+			status: data.status,
+			merge_fields: {
+				FNAME: data.firstname ?? '',
+				LNAME: data.lastname ?? '',
+				COUNTRY: data.country ?? '',
+				LANGUAGE: data.language === 'de' ? 'German' : 'English',
+			},
+		});
+	};
+
+	// Helper function to calculate the MD5 hash
+	md5 = (str: string): string => {
+		const crypto = require('crypto');
+		return crypto.createHash('md5').update(str).digest('hex');
+	};
+}