Debugging 422 errors when generating preview

[mglaman]

I notice that the preview API callback handler has this:

    } catch (error) {
      return response.status(422).end()
    }

That makes it a bit hard to debug why we're getting back a 422 response. Are there tips and tricks for debugging this in a containerized production environment where it isn't easy to say "oh just add some debugging quick." All of our secrets match up. I just have no idea where it's getting an error.

It's not preview URL validation as that handles !response.ok so it must be in:

      const validationPayload = await result.json()

      response.setPreviewData({
        resourceVersion,
        plugin,
        ...validationPayload,
      })

But I have no idea why. Do I just copy/paste this code and temporarily fork the preview endpoint?

[p0zi]

Try configuring on Drupal in settings.php reverse proxy, for ex.:

$settings['reverse_proxy'] = TRUE; $settings['reverse_proxy_addresses'] = ['172.16.0.1']; // Depending on network configuration $settings['reverse_proxy_trusted_headers'] = \Symfony\Component\HttpFoundation\Request::HEADER_X_FORWARDED_FOR | \Symfony\Component\HttpFoundation\Request::HEADER_X_FORWARDED_HOST | \Symfony\Component\HttpFoundation\Request::HEADER_X_FORWARDED_PORT | \Symfony\Component\HttpFoundation\Request::HEADER_X_FORWARDED_PROTO | \Symfony\Component\HttpFoundation\Request::HEADER_FORWARDED;

[mglaman]

Yep. That's configured and not the issue. This issue is about finding ways to get better error messages returned inside of the client here.

[kevinquillen]

Have this very same issue using OOTB NextJs for Drupal. I have no idea why I am getting a 422 or where to begin debugging this issue.

[kevinquillen]

In Drupal, I get this log but don't know where it is originating:

Symfony\Component\HttpKernel\Exception\MethodNotAllowedHttpException: No route found for "GET https://drupalnextjs.ddev.site/next/preview-url": Method Not Allowed (Allow: POST) in Symfony\Component\HttpKernel\EventListener\RouterListener->onKernelRequest() (line 131 of /var/www/html/vendor/symfony/http-kernel/EventListener/RouterListener.php).

The route definition for this from the NextJS module defines it as POST only.