PDFRenderer Error: "New call routed to draining downlink"

What I’m trying to do:

I have a background task that runs and creates several PDF documents. When ran this morning, about halfway through 20/40 documents it started to error with the following message:

“New call routed to draining downlink.”

Is this a new error message in PDFREnderer? Any idea what it could hint to?


Whoops! I know what this is, and have committed a fix.

Background for the interested: We’ve been redeploying some server infrastructure today. Normally this should be entirely invisible to you – if you have code that’s running a background task, and it’s running on the old infrastructure, we’ll politely keep your code running on the old infra while it finishes, while routing new calls to a new instance on the new infrastructure. However, due to a quirk of how Anvil’s PDF rendering works, if you request a PDF render the PDF renderer goes back to the server code, wherever it’s running (after the headless Chrome has booted) to request the data to render – and this was broken if you caught it at the right stage of the shutdown/restart cycle.

The code fix for that is now pushed, and should be deployed before we next have to do any migrations like that :slight_smile:


Thanks! The error message seemed odd enough to ask :slight_smile: Glad it was easily identifiable!