SoulSync/Support/DOCKER-OAUTH-FIX.md

🔐 Docker OAuth Authentication Fix

Problem: "Insecure redirect URI" Error

When accessing SoulSync from a different device than the Docker host, you may encounter:

• INVALID_CLIENT: Insecure redirect URI
• Spotify authentication failed: error: invalid_client

Why this happens: Spotify requires HTTPS for OAuth callbacks when not using localhost.

✅ Simple Solution: SSH Port Forwarding

Step 1: Set up SSH tunnel from your device to Docker host

On the device you're browsing from (laptop/phone/etc):

# Replace 'user' and 'docker-host-ip' with your actual values
ssh -L 8888:localhost:8888 -L 8889:localhost:8889 user@docker-host-ip

# Example:
ssh -L 8888:localhost:8888 -L 8889:localhost:8889 john@192.168.1.100

Keep this SSH connection open while using SoulSync.

Step 2: Configure OAuth redirect URIs

In your Spotify Developer App:

• Set redirect URI to: http://127.0.0.1:8888/callback

In your Tidal Developer App:

• Set redirect URI to: http://127.0.0.1:8889/tidal/callback

In SoulSync Settings:

• Set Spotify redirect URI to: http://127.0.0.1:8888/callback
• Set Tidal redirect URI to: http://127.0.0.1:8889/tidal/callback

Step 3: Use SoulSync normally

• Access SoulSync: http://docker-host-ip:8008 (normal HTTP)
• OAuth callbacks will tunnel through SSH to localhost
• Authentication will work without HTTPS requirements

🖥️ Alternative: Direct Access from Docker Host

If you can access SoulSync directly from the Docker host machine:

• Use: http://127.0.0.1:8008
• Set OAuth redirect URIs to localhost (as above)
• No SSH tunnel needed

🔧 For Advanced Users: Reverse Proxy

Set up nginx/traefik with proper SSL certificates for true HTTPS support. See community guides for Docker reverse proxy setups.

📝 Summary

The core issue is that Spotify requires HTTPS for non-localhost OAuth redirects. The SSH tunnel makes remote devices appear as localhost to bypass this requirement.

Key points:

• ✅ Always use 127.0.0.1 in OAuth redirect URIs
• ✅ Use SSH tunnel when accessing from different device
• ✅ Keep tunnel open during authentication
• ✅ Works with existing Docker setup - no changes needed