Send subscription renewal reminders via Telegram with Supabase

Subscription Renewal Reminder – Telegram & Supabase This workflow tracks upcoming subscription expiry dates stored in Supabase and automatically sends personalized renewal-reminder messages to each customer via Telegram. It is designed to be triggered by an HTTP Webhook (manually or on a schedule) and ensures that customers are notified a configurable number of days before their subscription lapses. > Community Template Disclaimer > This is a community-contributed n8n workflow template. It is provided “as-is” without official support from n8n GmbH. Always test thoroughly before using in production. Pre-conditions/Requirements Prerequisites - n8n instance (self-hosted or n8n.cloud) - Supabase project with a subscriptions table (id, customername, expirationdate, telegramchatid, notified) - A Telegram Bot created via @BotFather - Outbound HTTPS access from n8n to api.telegram.org and your Supabase project REST endpoint Required Credentials - Supabase Service Role Key – Full access for reading/writing the subscriptions table - Telegram Bot Token – To send messages from your bot - n8n Webhook URL – Auto-generated when you activate the workflow (ScrapeGraphAI API Key is not required for this non-scraping workflow.) Specific Setup Requirements | Environment Variable | Example Value | Purpose | |----------------------|--------------|---------| | SUPABASEURL | https://xyzcompany.supabase.co | Base URL for Supabase REST API | | SUPABASEKEY | eyJhbGciOiJI... | Service Role Key | | TELEGRAMTOKEN | 609012345:AA... | Bot token obtained from BotFather | | REMINDERDAYS | 3 | Days before expiry to notify | How it works This workflow tracks upcoming subscription expiry dates stored in Supabase and automatically sends personalized renewal-reminder messages to each customer via Telegram. It is triggered by an HTTP Webhook (manually or via external scheduler) and ensures that customers are notified a configurable number of days before their subscription lapses. Key Steps: - Receive Trigger (Webhook): External call fires the workflow or an internal Cron node can be added. - Set Static Parameters: The Set node calculates “today + REMINDERDAYS”. - Query Supabase: Fetch all subscriptions expiring on or before the calculated date and not yet notified. - Branch Logic (If node): Check if any subscriptions were returned. - Loop & Dispatch (Code + Telegram nodes): Iterate over each customer row, compose a message, and send via Telegram. - Flag as Notified (Supabase Update): Update each processed row to prevent duplicate reminders. - Respond to Webhook: Return a concise JSON summary for logging or downstream integrations. Set up steps Setup Time: 15–20 minutes 1. Create Telegram Bot a. Open Telegram and talk to @BotFather → /newbot b. Copy the given bot token; paste it into n8n Telegram credentials. 2. Prepare Supabase a. Create a table named subscriptions with columns: id (uuid), customername (text), expirationdate (date), telegramchatid (text), notified (bool, default false) b. Obtain the Service Role Key from Project Settings → API. 3. Import the Workflow a. In n8n, click Templates → Import and select “Subscription Renewal Reminder – Telegram & Supabase”. b. Replace placeholder credentials in the Supabase and Telegram nodes. 4. Define Environment Variables (Optional but recommended) Add SUPABASEURL, SUPABASEKEY, TELEGRAMTOKEN, and REMINDERDAYS in Settings → Environment Variables for easy maintenance. 5. Activate the Workflow Copy the production webhook URL and (optionally) set up a cron job or n8n Cron node to hit it daily. Node Descriptions Core Workflow Nodes: - Webhook – Entry point; triggers the workflow via HTTP request. - Set (Calculate Target Date) – Defines targetDate = today + REMINDERDAYS. - Supabase (Select) – Retrieves expiring subscriptions that haven’t been notified. - If (Rows > 0?) – Determines whether to continue or exit early. - Code (For-Each Loop) – Iterates through each returned row to send messages and update status. - Tele