Fastify Plugin Timeout Error in Azure App Services

Get Help and Help Others
1

Fastify Plugin Timeout Error in Azure App Services

Environment

  • Deployment Platform: Azure App Services

Problem Description

I’m experiencing an error with my RedwoodJS application deployed to Azure App Services. The application was working fine previously, and I haven’t made any changes to the server-side code. The error occurs during startup:

2025-03-25T01:00:35.311903329Z FastifyError: fastify-plugin: Plugin did not start in time: 'redwoodFastifyAPI'. You may have forgotten to call 'done' function or to resolve a Promise
2025-03-25T01:00:35.311928199Z at manageErr (/app/node_modules/fastify/fastify.js:628:33)
2025-03-25T01:00:35.311931729Z at /app/node_modules/fastify/fastify.js:614:11
2025-03-25T01:00:35.311934529Z at Object._encapsulateThreeParam (/app/node_modules/avvio/boot.js:598:7)
2025-03-25T01:00:35.311937262Z at Boot.timeoutCall (/app/node_modules/avvio/boot.js:494:5)
2025-03-25T01:00:35.311940036Z at Boot.callWithCbOrNextTick (/app/node_modules/avvio/boot.js:476:19)
2025-03-25T01:00:35.311942889Z at release (/app/node_modules/fastq/queue.js:171:16)
2025-03-25T01:00:35.311945359Z at Object.resume (/app/node_modules/fastq/queue.js:103:7)
2025-03-25T01:00:35.311947826Z at /app/node_modules/avvio/boot.js:116:18
2025-03-25T01:00:35.311950228Z at /app/node_modules/avvio/boot.js:437:7

The error suggests that the ‘redwoodFastifyAPI’ plugin is not starting within the expected time limit.

Questions

  1. Has anyone encountered this issue with RedwoodJS on Azure App Services?
  2. Are there any known issues with Fastify plugin timeouts?
  3. Are there any configuration changes I should make to increase the plugin timeout?
  4. Any other suggestions for debugging this issue?

Any help would be greatly appreciated!

2

I have also seemingly randomly just started having this issue when running locally with yarn rw dev.

Here’s an example of the output of that command for me:

node ➜ /workspace (develop) $ yarn rw dev
web |   ➜  Local:   http://localhost:8910/
web |   ➜  Network: http://172.22.0.4:8910/
api | Building...
gen | Generating full TypeScript definitions and GraphQL schemas
api | Took 6304 ms
api | Debugger listening on ws://127.0.0.1:18911/7b719e20-e8ab-4f06-9364-912a6105b89c
api | For help, see: https://nodejs.org/en/docs/inspector
gen | Done.
gen | 
gen | Created 402 in 5383 ms
api | Importing Server Functions... 
[...]
api | This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). The promise rejected with the reason:
api | FastifyError: Plugin did not start in time: 'redwoodFastifyAPI'. You may have forgotten to call 'done' function or to resolve a Promise
api |     at Timeout._onTimeout (/workspace/node_modules/avvio/lib/plugin.js:114:31)
api |     at listOnTimeout (node:internal/timers:581:17)
api |     at process.processTimers (node:internal/timers:519:7)
[...]
api | ...Done importing in 14475 ms

From there the API is unresponsive.

I have no idea why this process is taking longer suddenly. For me this came up after making one small random modification to a file triggering a server restart. Reverting that change makes no difference in the longer boot time now.

@declanb as a workaround you can extend (or disable) the Fastify plugin timeout by editting (or adding and modifying) the RedwoodJS Server File like so:

@@ -7,6 +7,9 @@ import { logger } from 'src/lib/logger'
 async function main() {
   const server = await createServer({
     logger,
+    fastifyServerOptions: {
+      pluginTimeout: 0,
+    },
   })
 
   await server.start()
3

I had one of my devs also test this. They get the same sort of startup timings but they don’t get the plugin timeout error, oddly.

web | Re-optimizing dependencies because lockfile has changed
web |   ➜  Local:   http://localhost:8910/
web |   ➜  Network: http://172.18.0.5:8910/
api | Building...
gen | Generating full TypeScript definitions and GraphQL schemas
api | Took 8085 ms
api | Debugger listening on ws://127.0.0.1:18911/a6c6ddce-6180-43b1-a62e-5132a3a661fe
api | For help, see: https://nodejs.org/en/docs/inspector
gen | Done.
api | Importing Server Functions... 
[...]
api | ...Done importing in 13282 ms
api | GraphQL Yoga Server endpoint at graphql
api | GraphQL Yoga Server Health Check endpoint at graphql/health
api | GraphQL Yoga Server Readiness endpoint at graphql/readiness
api | 19:14:09 🌲 Server listening at http://[::]:8911
api | Server listening at http://[::]:8911/

The default fastify plugin timeout is 10s so from my own example this kind of made sense given the 14s build and function import time. But my other dev has the same exact code and takes 13s but does not hit the error. :person_shrugging: