Hitting a frustrating wall with a new Auth0 extension that's failing without any useful logs. The extension appears to activate, but the intended action never happens, and the Auth0 logs dashboard shows nothing but successful executions. I've been down this road before with silent failures in serverless environments.
Here's the basic setup I'm working with:
- Extension: A custom `on-execute-post-login` action.
- Trigger: It's correctly listed and enabled for the desired flow.
- Code: Simple Node.js function that should perform an external API call.
The core issue is the lack of visibility. Has anyone else encountered this? I'm looking for the typical blind spots.
My immediate checklist for silent extension failures usually includes:
* **Secrets/Configuration:** Verified the required secrets are set in the extension's configuration and are being accessed correctly via `event.secrets`. A typo here is a classic culprit.
* **External Dependencies:** The extension's network egress. Does it need to reach an internal VPN or a whitelisted IP? Auth0's shared environment might be blocked.
* **Timeout & Async Handling:** Ensuring the action properly `await`s any promises and doesn't exceed the runtime limit. An unhandled rejection can vanish.
* **Logging Destination:** Double-checked that I'm looking at the "Logs" for the specific Action/Extension, not just the main tenant logs.
A snippet of the action code, sanitized:
```javascript
exports.onExecutePostLogin = async (event, api) => {
// This console.log never appears anywhere I can find
console.log('Extension triggered for:', event.user.email);
const response = await fetch(event.secrets.MY_API_ENDPOINT, {
method: 'POST',
headers: { 'Authorization': `Bearer ${event.secrets.API_KEY}` },
body: JSON.stringify({ user_id: event.user.user_id })
});
if (!response.ok) {
// Does this failure surface?
console.error('API call failed:', response.status);
}
};
```
What are the most effective ways to force some logging to appear, or to debug the execution path? Are there specific permissions or tenant settings that could be intercepting the failure before it hits the logs?
Ah, the classic "logs show nothing but successful executions" paradox. My money's on the external API call being the silent killer. It probably *is* failing, but Auth0's own logging only captures the extension's runtime container, not the outcome of your outbound HTTP request.
You mentioned checking egress, which is good. But have you confirmed the external service's response format? I've seen APIs return a 200 OK with a JSON body that's actually an error, which your code might be swallowing. Or worse, a timeout that isn't being caught because your async handling assumes a quick reply.
Add some nuclear-grade try-catch logging inside the function that writes to a third-party logging service. It's ugly, but it's the only way to see what's vanishing into the void.
Data skeptic, not a data cynic.
Third-party logging is the right instinct, but that's a new vendor lock-in and a fresh monthly bill. You're solving for visibility while ignoring the cost leak that just opened. Instead of blindly adding services, measure the runtime first.
Spin up a cheap compute instance with a logging endpoint, run the extension there for a fraction of what a SaaS logger costs, and capture the failures. If the API call is the issue, you'll see it. Then you can decide if the fix is worth a permanent observability tax.
Everyone jumps to "add more tooling" before they even know what they're paying to observe.
pay for what you use, not what you reserve