feat(billing): add free/premium tier limits for webhooks and monitors

- Free users limited to 1 webhook and 1 monitor
- Premium users can have up to 10 webhooks and 10 monitors
- Add DISABLE_WEBHOOK_NOTIFICATIONS config option
- Update docker-compose to separate API and worker responsibilities
- API service now only handles requests, worker handles all notifications
- Return 403 with upgrade message when free users hit limits

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: dtfiedler

docker-compose.yaml

@@ -18,8 +18,12 @@ services:
       - AWS_SECRET_ACCESS_KEY=${AWS_SECRET_ACCESS_KEY:-}
       - AWS_REGION=${AWS_REGION:-us-east-1}
       - AWS_FROM_EMAIL=${AWS_FROM_EMAIL:-}
+      # API only handles requests - all notifications handled by worker
       - DISABLE_EMAIL_NOTIFICATIONS=true
+      - DISABLE_WEBHOOK_NOTIFICATIONS=true
       - DISABLE_EVENT_PROCESSING=true
+      - DISABLE_GATEWAY_MONITORING=true
+      - DISABLE_ARNS_SYNC=true
       - ENABLE_HOSTED_FRONTEND=false
       - FRONTEND_URL=${FRONTEND_URL:-https://subscribe.permagate.io}
       - SECRET_KEY=${SECRET_KEY:-}
@@ -45,7 +49,12 @@ services:
       - AWS_SECRET_ACCESS_KEY=${AWS_SECRET_ACCESS_KEY:-}
       - AWS_REGION=${AWS_REGION:-us-east-1}
       - AWS_FROM_EMAIL=${AWS_FROM_EMAIL:-}
+      # Worker handles all notifications and background processing
       - DISABLE_EMAIL_NOTIFICATIONS=${DISABLE_EMAIL_NOTIFICATIONS:-false}
+      - DISABLE_WEBHOOK_NOTIFICATIONS=${DISABLE_WEBHOOK_NOTIFICATIONS:-false}
+      - DISABLE_EVENT_PROCESSING=${DISABLE_EVENT_PROCESSING:-false}
+      - DISABLE_GATEWAY_MONITORING=${DISABLE_GATEWAY_MONITORING:-false}
+      - DISABLE_ARNS_SYNC=${DISABLE_ARNS_SYNC:-false}
       - ENABLE_SLACK_NOTIFICATIONS=${ENABLE_SLACK_NOTIFICATIONS:-false}
       - SLACK_WEBHOOK_URL=${SLACK_WEBHOOK_URL:-}
       - ENABLE_DISCORD_NOTIFICATIONS=${ENABLE_DISCORD_NOTIFICATIONS:-false}

src/config.ts

@@ -33,6 +33,10 @@ export const auth0ClientSecret = process.env.AUTH0_CLIENT_SECRET;
 // Email
 export const disableEmails = process.env.DISABLE_EMAIL_NOTIFICATIONS === 'true';
 
+// Webhooks (subscriber-defined webhooks)
+export const disableWebhookNotifications =
+  process.env.DISABLE_WEBHOOK_NOTIFICATIONS === 'true';
+
 // Notifications
 export const slackWebhookUrl = process.env.SLACK_WEBHOOK_URL;
 export const enableSlackNotifications =
@@ -103,6 +107,21 @@ export const gatewayHealthcheckTimeoutMs = process.env
   .GATEWAY_HEALTHCHECK_TIMEOUT_MS
   ? +process.env.GATEWAY_HEALTHCHECK_TIMEOUT_MS
   : 10000;
+// Subscriber limits (free vs premium)
+export const freeWebhookLimit = process.env.FREE_WEBHOOK_LIMIT
+  ? +process.env.FREE_WEBHOOK_LIMIT
+  : 1;
+export const premiumWebhookLimit = process.env.PREMIUM_WEBHOOK_LIMIT
+  ? +process.env.PREMIUM_WEBHOOK_LIMIT
+  : 10;
+export const freeMonitorLimit = process.env.FREE_MONITOR_LIMIT
+  ? +process.env.FREE_MONITOR_LIMIT
+  : 1;
+export const premiumMonitorLimit = process.env.PREMIUM_MONITOR_LIMIT
+  ? +process.env.PREMIUM_MONITOR_LIMIT
+  : 10;
+
+// Legacy config - now uses tier-based limits
 export const maxMonitorsPerSubscriber = process.env.MAX_MONITORS_PER_SUBSCRIBER
   ? +process.env.MAX_MONITORS_PER_SUBSCRIBER
   : 3;

src/db/sqlite.ts

@@ -539,6 +539,14 @@ export class SqliteDatabase implements SubscriberStore, EventStore {
     return deleted > 0;
   }
 
+  async getWebhookCountForSubscriber(subscriberId: number): Promise<number> {
+    const result = await this.knex('webhooks')
+      .where({ subscriber_id: subscriberId })
+      .count<{ count: string | number }>('* as count')
+      .first();
+    return Number(result?.count || 0);
+  }
+
   // Webhook Events (linking) Methods
   async addWebhookEvent(webhookId: number, eventType: string): Promise<void> {
     await this.knex<WebhookEventLink>('webhook_events')

src/routes/api.ts

@@ -644,6 +644,25 @@ apiRouter.post(
         return res.status(404).json({ error: 'Subscriber not found' });
       }
 
+      // Check webhook limit based on subscription tier
+      const { freeWebhookLimit, premiumWebhookLimit } = await import(
+        '../config.js'
+      );
+      const webhookLimit = subscriber.premium
+        ? premiumWebhookLimit
+        : freeWebhookLimit;
+      const webhookCount = await req.db.getWebhookCountForSubscriber(
+        subscriber.id,
+      );
+      if (webhookCount >= webhookLimit) {
+        const upgradeMessage = subscriber.premium
+          ? ''
+          : ' Upgrade to premium for up to 10 webhooks.';
+        return res.status(403).json({
+          error: `Maximum ${webhookLimit} webhook${webhookLimit === 1 ? '' : 's'} allowed for your subscription tier.${upgradeMessage}`,
+        });
+      }
+
       const { url, description, type, active, authorization } = req.body;
 
       if (!url || typeof url !== 'string') {
@@ -1527,14 +1546,22 @@ apiRouter.post(
         return res.status(400).json({ error: 'Invalid FQDN format' });
       }
 
-      // Check monitor limit (max 3 per subscriber)
-      const { maxMonitorsPerSubscriber } = await import('../config.js');
+      // Check monitor limit based on subscription tier
+      const { freeMonitorLimit, premiumMonitorLimit } = await import(
+        '../config.js'
+      );
+      const monitorLimit = subscriber.premium
+        ? premiumMonitorLimit
+        : freeMonitorLimit;
       const monitorCount = await req.db.getMonitorCountForSubscriber(
         subscriber.id,
       );
-      if (monitorCount >= maxMonitorsPerSubscriber) {
-        return res.status(400).json({
-          error: `Maximum ${maxMonitorsPerSubscriber} monitors allowed per subscriber`,
+      if (monitorCount >= monitorLimit) {
+        const upgradeMessage = subscriber.premium
+          ? ''
+          : ' Upgrade to premium for up to 10 monitors.';
+        return res.status(403).json({
+          error: `Maximum ${monitorLimit} monitor${monitorLimit === 1 ? '' : 's'} allowed for your subscription tier.${upgradeMessage}`,
         });
       }
 

src/system.ts

@@ -86,7 +86,7 @@ const twitterNotifier = config.twitterBearerToken
 const webhookNotifier = new WebhookNotificationProvider({
   db,
   logger,
-  enabled: true,
+  enabled: !config.disableWebhookNotifications,
 });
 
 // Create composite notification provider with all enabled providers
@@ -216,6 +216,11 @@ async function sendGatewayMonitorWebhook(
   alertType: string,
   data: MonitorAlertData,
 ): Promise<void> {
+  if (config.disableWebhookNotifications) {
+    logger.debug('Webhook notifications are disabled, skipping gateway monitor webhook');
+    return;
+  }
+
   const payload = formatGatewayMonitorWebhookPayload(webhook.type, alertType, data);
 
   const headers: Record<string, string> = {