Readme for web ui

Author: cschleiden

web/app/README.md

@@ -1 +1,11 @@
-# Diagnostic web ui
+# Diagnostic Web UI
+
+This is a basic diagnostic web UI. It's written as a small React application, bootstrapped with create-react-app, which is then embedded in its compiled form with Go `embed` into the binary.
+
+## Testing changes
+
+`npm start` to start the development server, and then run a go-workflows sample that hosts the web UI. The `proxy` configuration in `package.json` should allow you to access the web ui from the auto-reloading development server, and serve the API via your Go binary.
+
+## Checking in changes
+
+`npm run build` to update the compiled application in `./build`. The build output has to be committed to the repository, it is embedded by the Go API.