Strava webhooks implementation

This document describes the complete webhook implementation for real-time Strava activity notifications.

Overview

The webhook system eliminates the need for continuous polling by receiving push notifications from Strava when activities are created, updated, or deleted. This provides:

• Instant notifications - Activities appear in your app seconds after upload.
• Reduced API usage - No more polling every 4 hours.
• Better user experience - Real-time sync without manual intervention.
• Scalable architecture - Handles multiple users efficiently.

Architecture

Strava Activity Upload
         ↓
Strava Webhook Event (POST /api/strava/webhook)
         ↓
ActivityFetchJob created in database
         ↓
Activity Fetch Worker processes job
         ↓
Fetch activity details from Strava API
         ↓
Save to database + create thumbnail job

Components

1. Webhook Handler (/api/strava/webhook) - Receives events from Strava.
2. Job Queue (ActivityFetchJob model) - Queues activities for processing.
3. Activity Fetch Worker - Processes jobs with rate limiting.
4. Rate Limiter - Token bucket algorithm for API limits.
5. Admin Endpoints - Manage subscriptions and monitor queue.

Database schema

ActivityFetchJob model

CREATE TABLE "ActivityFetchJob" (
    "id" BIGSERIAL PRIMARY KEY,
    "activityId" BIGINT NOT NULL UNIQUE,  -- Strava activity ID
    "athleteId" BIGINT NOT NULL,          -- Strava athlete ID
    "reason" TEXT NOT NULL,               -- "webhook", "polling", "manual"
    "force" BOOLEAN DEFAULT false,        -- Force re-fetch existing
    "status" TEXT DEFAULT 'pending',      -- pending | working | done | failed
    "attempts" INTEGER DEFAULT 0,         -- Retry counter
    "maxAttempts" INTEGER DEFAULT 5,      -- Max retries
    "nextRunAt" TIMESTAMP DEFAULT NOW(),  -- When to try next (backoff)
    "error" TEXT,                         -- Last error message
    "createdAt" TIMESTAMP DEFAULT NOW(),
    "updatedAt" TIMESTAMP DEFAULT NOW()
);

CREATE INDEX "ActivityFetchJob_status_nextRunAt_idx" ON "ActivityFetchJob"("status", "nextRunAt");
CREATE INDEX "ActivityFetchJob_athleteId_idx" ON "ActivityFetchJob"("athleteId");
CREATE INDEX "ActivityFetchJob_reason_idx" ON "ActivityFetchJob"("reason");

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Setup instructions

1. Environment variables

Add these to your .env file:

# Required - Strava API credentials
STRAVA_CLIENT_ID=your_client_id
STRAVA_CLIENT_SECRET=your_client_secret
NEXT_PUBLIC_BASE_URL=https://your-domain.com

# Webhook verification token (generate a random string)
STRAVA_VERIFY_TOKEN=your-random-string-123

# Optional - Rate limiting (defaults shown)
STRAVA_RATE_LIMIT_CAPACITY=600        # 600 requests per 15 minutes
STRAVA_RATE_LIMIT_INTERVAL=900000     # 15 minutes in ms
STRAVA_ATHLETE_COOLDOWN=15000         # 15 seconds between athlete fetches

2. Database migration

The migration was applied through this command:

npx prisma migrate dev --name add_activity_fetch_jobs

3. Start the workers

The new activity fetch worker runs alongside existing workers:

# Development (includes all 4 workers)
npm run dev

# Production
npm start

You should see:

[activity-fetch-worker] Started. Checking for jobs every 2000 ms
[thumb-worker] started. Debug: false | Size: 256 | NoBasemap: false | mapSource: OpenStreetMap
[strava-worker] started. interval: 240min checking every 4h | auto-sync enabled (stopAfter=20)

4. Create webhook subscription

Option A: Using admin API

curl -X POST http://localhost:3000/api/admin/webhooks \
  -H "Content-Type: application/json" \
  -d '{
    "callbackUrl": "https://your-domain.com/api/strava/webhook",
    "verifyToken": "your-random-string-123"
  }'

Option B: Using setup script

# List existing subscriptions
npm run webhook:list

# Create new subscription
npm run webhook:create

# Clean up all subscriptions
npm run webhook:clean

Option C: Manual setup script

# First, get your access token from the database
npx tsx -e "import { prisma } from './src/lib/db'; prisma.stravaToken.findMany().then(console.log)"

# Set token and run setup
STRAVA_ACCESS_TOKEN=your_token npx tsx scripts/setup-webhooks.ts create

5. Verify webhook is operational

1. Upload an activity to Strava.
2. Check the job queue: curl http://localhost:3000/api/admin/activity-jobs.
3. Activity should appear in your app within seconds.

---

Monitoring and management

Job queue statistics

# Get queue stats and recent jobs
curl http://localhost:3000/api/admin/activity-jobs

# Filter by status
curl http://localhost:3000/api/admin/activity-jobs?status=failed&limit=10

Webhook subscriptions

# List current subscriptions
curl http://localhost:3000/api/admin/webhooks

# Delete specific subscription
curl -X DELETE http://localhost:3000/api/admin/webhooks?id=12345

# Delete all subscriptions
curl -X DELETE http://localhost:3000/api/admin/webhooks

Manual job creation

# Create manual fetch job
curl -X POST http://localhost:3000/api/admin/activity-jobs \
  -H "Content-Type: application/json" \
  -d '{
    "activityId": "12345678",
    "athleteId": "87654321",
    "reason": "manual",
    "force": true
  }'

Cleanup completed jobs

# Delete completed jobs older than 24 hours
curl -X DELETE "http://localhost:3000/api/admin/activity-jobs?status=done&olderThan=24"

# Delete all failed jobs
curl -X DELETE "http://localhost:3000/api/admin/activity-jobs?status=failed"

---

Configuration

Rate limiting

The system uses a token bucket algorithm to respect Strava's 600 requests per 15 minutes limit:

// Global rate limiter (shared across all athletes)
const stravaRateLimiter = new TokenBucket(600, 15 * 60 * 1000);

// Per-athlete cooldown (prevents spam for single athlete)
const athleteCooldown = new AthleteCooldown(15000); // 15 seconds

Worker behavior

• Concurrency: Max 3 concurrent API calls.
• Job claiming: Atomic database transactions prevent race conditions.
• Stale job recovery: Jobs stuck in "working" state are auto-reclaimed after 5 minutes.
• Backoff strategy: Exponential backoff with 30s base delay, capped at 1 hour.

Error handling

Error Type	Action
HTTP 404 (Not Found)	Mark failed permanently
HTTP 429 (Rate Limited)	Honor Retry-After header, reduce capacity
HTTP 401/403 (Auth)	Mark failed permanently
Network/5xx errors	Exponential backoff retry
Activity already exists	Skip if not forced

Migration from polling

The webhook system works alongside the existing polling system:

1. Webhooks handle real-time notifications for new activities.
2. Polling provides fallback reconciliation every 4 hours.
3. Manual sync still available for bulk operations.

To fully migrate:

1. Set up webhooks (this guide).
2. Optionally disable auto-sync: STRAVA_AUTO_SYNC_ENABLED=false.
3. Keep polling as weekly reconciliation: STRAVA_WORKER_INTERVAL_MS=604800000 (7 days).

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Troubleshooting

Webhook not receiving events

1. Check subscription status:

   npm run webhook:list

2. Verify callback URL is accessible:

   curl https://your-domain.com/api/strava/webhook?hub.mode=subscribe&hub.challenge=test&hub.verify_token=your-token

3. Check webhook logs:

   tail -f logs/webhook.log

Jobs getting stuck

1. Check worker is running:

   ps aux | grep activity-fetch-worker

2. Look for rate limiting:

   curl http://localhost:3000/api/admin/activity-jobs?status=pending&limit=5

3. Manually reclaim stale jobs:

   UPDATE "ActivityFetchJob"
   SET status = 'pending'
   WHERE status = 'working'
   AND "updatedAt" < NOW() - INTERVAL '5 minutes';

High error rate

1. Check token validity:

   curl -H "Authorization: Bearer YOUR_TOKEN" https://www.strava.com/api/v3/athlete

2. Monitor rate limits:

   # Check for 429 errors in job queue
   curl http://localhost:3000/api/admin/activity-jobs?status=failed | grep "rate limited"

3. Adjust worker concurrency:

   // In activity-fetch-worker.ts
   const MAX_CONCURRENT_JOBS = 1; // Reduce from 3 to 1

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Performance Impact

Before webhooks (polling)

• 1 API call every 4 hours per athlete.
• 20-50 activity detail fetches per sync.
• 4-6 hour delay for new activities.
• Wasted API calls when no new activities.

After webhooks

• 0 scheduled API calls.
• 1 activity detail fetch per new activity.
• <30 second delay for new activities.
• 95%+ reduction in API usage.

Queue processing times

• Typical job: 200-500ms (API call + database write).
• With thumbnails: +2-5 seconds for route rendering.
• Rate limited: 60-300 seconds delay.
• Failed job retry: 30s, 60s, 2m, 4m, 8m intervals.

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Success metrics

Once webhooks are working, you should see:

1. Near-instant activity appearance - Activities show up within 30 seconds of Strava upload.
2. Reduced API usage - From 600+ calls/day to <50 calls/day.
3. Lower latency - No more 4-hour delays.
4. Better reliability - No missed activities due to sync windows.

Monitor these endpoints for health:

• /api/admin/activity-jobs - Job queue health.
• /api/admin/webhooks - Subscription status.
• Worker logs - Processing efficiency.

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The app receives real-time activity notifications! Upload an activity to Strava and watch it appear in the app within seconds.