run-rask

name	run-rask
description	Build, launch, and drive the Rask Server showcase app (samples/Rask.Example.Server) — the server-rendered, live-over-WebSocket demo of the framework. Use to run/start/launch the app, take a screenshot, or confirm a UI change works in the real running app (not just tests). Drives it headlessly with a committed C# Playwright driver — pure .NET, no Node.

Run the Rask showcase

samples/Rask.Example.Server is the framework's showcase: plain-C# components, server-rendered and live-updated over a WebSocket (the browser posts data-rask-on-* events, the server re-renders and streams back a DOM diff). It's the app to launch when you want to see a change.

curl can only see the first server-rendered HTML — it can never observe the live loop. To prove interactivity you need a real browser. The committed driver .claude/skills/run-rask/driver.cs does that with the repo's existing Microsoft.Playwright (.NET) dependency — the same version the E2E suite uses, browsers already in the ms-playwright cache. It's a .NET 10 file-based app: no Node, no npm, no csproj — just dotnet run driver.cs.

All paths below are relative to the repo root (the unit). Run everything from there unless told otherwise.

Prerequisites

• .NET 10 SDK — dotnet --version → 10.0.302 here. That's the whole toolchain; the driver pulls Microsoft.Playwright via NuGet (version comes from Directory.Packages.props, so the #:package directive is intentionally unversioned — Central Package Management supplies it).
• Playwright browsers — already present in ~/Library/Caches/ms-playwright (installed for the E2E suite). If missing, the driver errors with a "browser not found" message; install with dotnet run --project tests/Rask.Examples.E2E.Tests -- ... build once then run the generated playwright.ps1 install chromium, or see scripts/run-e2e-local.sh.

Build

dotnet build samples/Rask.Example.Server -c Debug -m:1

~3–8s. Pulls in Rask.Core, Rask.Server, Rask.Bootstrap, the generators, and the shared sample assembly. Clean build = 0 warnings.

Run (agent path)

1. Launch the server in the background (override the port explicitly; check it's free first):

   lsof -ti :5099 && echo "BUSY — see Gotchas" || echo "free"
   ASPNETCORE_ENVIRONMENT=Development \
     dotnet run --project samples/Rask.Example.Server -c Debug --no-build \
     --urls http://localhost:5099 > /tmp/rask-server.log 2>&1 &
   

2. Wait for it, smoke it with curl (initial HTML only):

   for i in $(seq 1 30); do curl -sf http://localhost:5099/ -o /dev/null && { echo "UP (${i}s)"; break; }; sleep 1; done
   curl -s http://localhost:5099/ | grep -o '<title>[^<]*</title>'   # → <title>Rask</title>
   

3. Drive it with the C# Playwright driver — screenshots + the live WebSocket round-trip. Run it from the skill directory so screenshots land in ./screenshots/:

   cd .claude/skills/run-rask
   dotnet run driver.cs all          # screenshots home/todos/table/routing + toggles a todo over WS
   

   Expected output (this is what it printed here):

   Driving http://localhost:5099  (all)
     OK /                      200  "Guides — Rask"  -> home.png
     OK /todos                 200  "Todos — Rask"  -> todos.png
     OK /table                 200  "Data table — Rask"  -> table.png
     OK /routing-demo/about    200  "Rask — feature showcase"  -> routing-about.png
     OK /todos checkbox toggled over WS: False -> True  -> todos-toggled.png
   done.
   

   Screenshots land in .claude/skills/run-rask/screenshots/. Open one (e.g. todos-toggled.png shows the flipped checkbox) to confirm the render is real.

   Driver commands: shots (screenshots only, the default), todos (interactive WS proof only), all. Point it at another port with a second arg: dotnet run driver.cs all http://localhost:5199.

4. Stop the server when done:

   lsof -ti :5099 | xargs kill
   

Run (human path)

dotnet run --project samples/Rask.Example.Server

Serves on http://localhost:5099 (from Properties/launchSettings.json); open it in a browser. Useless for automation — it blocks the terminal and opens nothing headlessly. Ctrl-C to stop.

Gotchas

• curl sees a dead page. The showcase only becomes interactive once the browser opens the WebSocket. Any "does clicking work?" question must go through driver.cs, not curl.
• /counter from the README is NOT a live route. It's a doc snippet. The showcase's real routes come from the sidebar: / (guides), /todos, /table, /routing-demo/about, /server-pwa, and the device-API demos (/serial, /usb, /bluetooth, /wake-lock, …). Hitting a bogus path returns a styled 200 "Page not found" — don't mistake it for a working page.
• Port 5099 is shared and hardcoded. It's the same port the E2E gate (scripts/run-e2e-local.sh) and every other worktree use. If lsof -ti :5099 shows it busy, a different build is answering your requests and your driver will silently test the wrong app. Launch on another port (--urls http://localhost:5199) and pass dotnet run driver.cs all http://localhost:5199. The pre-push hook also runs E2E on 5099, so a server you left running there will block a push.
• The driver is a file-based app, so two #:property lines are load-bearing. #:package Microsoft.Playwright is deliberately unversioned — the repo enforces Central Package Management, which forbids a version on the reference and supplies 1.61.0 itself; adding @1.61.0 fails with NU1008. And JsonSerializerIsReflectionEnabledByDefault=true is required because file-based apps disable reflection-based System.Text.Json by default, which Playwright's transport needs (without it: Reflection-based serialization has been disabled).
• Native samples don't build here. Rask.Example.Native{,.Server} multi-target net10.0-ios;net10.0-android and are excluded from Rask.slnx; without the mobile workloads they won't restore. This skill is the web showcase only.

Troubleshooting

• error NU1008: … cannot define a value for Version: Microsoft.Playwright → you added a version to the #:package directive; remove it (CPM owns the version — see Gotchas).
• Reflection-based serialization has been disabled on Playwright.CreateAsync() → the #:property JsonSerializerIsReflectionEnabledByDefault=true line is missing from driver.cs.
• Driver hangs on WaitForFunctionAsync / times out → the server isn't up on the base URL's port, or another worktree grabbed 5099. Re-check step 1's lsof and curl.
• dotnet run --project … exits immediately with an address-in-use bind error → 5099 is taken; pick another port (see Gotchas) or kill the holder with lsof -ti :5099 | xargs kill.