Advanced Zoom Apps Sample - Error: Not found

I downloaded the advanced sample app, followed the steps in the readme, and the app builds without errors. However, I get the following “Error: Not found” message when launching the app in zoom (see below).

Steps to recreate the issue:

  1. Download Advanced Zoom Apps Sample
  2. Run ngrok http 3000.
  3. Create .env file.
  4. Create app in Zoom Marketplace.
  5. Update .env file.
  6. Run docker-compose up
  7. Open Zoom and add the app.
Error: Not found at /home/node/app/server.js:50:17 
at Layer.handle [as handle_request] (/home/node/app/node_modules/express/lib/router/layer.js:95:5) 
at trim_prefix (/home/node/app/node_modules/express/lib/router/index.js:328:13) 
at /home/node/app/node_modules/express/lib/router/index.js:286:9 
at Function.process_params (/home/node/app/node_modules/express/lib/router/index.js:346:12)
at next (/home/node/app/node_modules/express/lib/router/index.js:280:10) 
at setResponseHeaders (/home/node/app/middleware.js:21:5) 
at Layer.handle [as handle_request] (/home/node/app/node_modules/express/lib/router/layer.js:95:5) 
at trim_prefix (/home/node/app/node_modules/express/lib/router/index.js:328:13) 
at /home/node/app/node_modules/express/lib/router/index.js:286:9

I figured out the issue, unlike the Zoom Apps JavaScript Sample, this app will not load in a browser. It only works when opened in Zoom. Now I need to figure out why the API calls aren’t working.