dream: hello + counter demos + 10 end-to-end tests

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/dream/conformance.sh

@@ -31,6 +31,8 @@ MODULES=(
   "lib/dream/websocket.sx"
   "lib/dream/static.sx"
   "lib/dream/run.sx"
+  "lib/dream/demos/hello.sx"
+  "lib/dream/demos/counter.sx"
 )
 
 # Suites: NAME RUNNER-FN PATH
@@ -44,6 +46,7 @@ SUITES=(
   "websocket   dream-ws-tests-run!  lib/dream/tests/websocket.sx"
   "static      dream-st-tests-run!  lib/dream/tests/static.sx"
   "run         dream-rn-tests-run!  lib/dream/tests/run.sx"
+  "demos       dream-dm-tests-run!  lib/dream/tests/demos.sx"
 )
 
 TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT

lib/dream/demos/counter.sx

@@ -0,0 +1,35 @@
+;; lib/dream/demos/counter.sx — per-session visit counter (counter.ml).
+;; Demonstrates the session middleware: each browser session keeps its own count.
+
+(define
+  dream-counter-handler
+  (fn
+    (req)
+    (let
+      ((n (+ 1 (or (dream-session-field req "count") 0))))
+      (begin
+        (dream-set-session-field req "count" n)
+        (dream-html (str "<p>You have visited this page " n " time(s).</p>"))))))
+
+;; reset clears the session counter
+(define
+  dream-counter-reset
+  (fn
+    (req)
+    (begin
+      (dream-set-session-field req "count" 0)
+      (dream-redirect "/"))))
+
+(define
+  dream-counter-app-with
+  (fn
+    (backend)
+    ((dream-sessions backend)
+      (dream-router
+        (list
+          (dream-get "/" dream-counter-handler)
+          (dream-post "/reset" dream-counter-reset))))))
+
+(define dream-counter-app (dream-counter-app-with (dream-memory-sessions)))
+
+;; entry point: (dream-run (dream-counter-app-with (dream-memory-sessions)))

lib/dream/demos/hello.sx

@@ -0,0 +1,16 @@
+;; lib/dream/demos/hello.sx — the canonical Dream "Hello, World!" (hello.ml).
+;; Dream.run (Dream.router [Dream.get "/" (fun _ -> Dream.html "Hello!")]).
+
+(define
+  dream-hello-app
+  (dream-router
+    (list
+      (dream-get "/" (fn (req) (dream-html "<h1>Hello, World!</h1>")))
+      (dream-get
+        "/hello/:name"
+        (fn
+          (req)
+          (dream-html (str "<h1>Hello, " (dream-param req "name") "!</h1>")))))))
+
+;; entry point (installs the handler on the host):
+;;   (dream-run dream-hello-app)

lib/dream/tests/demos.sx

@@ -0,0 +1,83 @@
+;; lib/dream/tests/demos.sx — end-to-end demo apps exercising the full stack.
+
+(define dream-dm-pass 0)
+(define dream-dm-fail 0)
+(define dream-dm-fails (list))
+
+(define
+  dream-dm-test
+  (fn
+    (name actual expected)
+    (if
+      (= actual expected)
+      (set! dream-dm-pass (+ dream-dm-pass 1))
+      (begin
+        (set! dream-dm-fail (+ dream-dm-fail 1))
+        (append! dream-dm-fails {:name name :actual actual :expected expected})))))
+
+(define
+  dream-dm-req
+  (fn (method target headers) (dream-request method target headers "")))
+
+;; ── hello ──────────────────────────────────────────────────────────
+(dream-dm-test
+  "hello root"
+  (dream-resp-body (dream-hello-app (dream-dm-req "GET" "/" {})))
+  "<h1>Hello, World!</h1>")
+(dream-dm-test
+  "hello name"
+  (dream-resp-body
+    (dream-hello-app (dream-dm-req "GET" "/hello/Ada" {})))
+  "<h1>Hello, Ada!</h1>")
+(dream-dm-test
+  "hello content-type"
+  (dream-resp-header
+    (dream-hello-app (dream-dm-req "GET" "/" {}))
+    "content-type")
+  "text/html; charset=utf-8")
+
+;; ── counter (sessions) ─────────────────────────────────────────────
+(define dream-dm-cbackend (dream-memory-sessions))
+(define dream-dm-capp (dream-counter-app-with dream-dm-cbackend))
+
+;; first visit: no cookie -> count 1, session cookie set
+(define dream-dm-c1 (dream-dm-capp (dream-dm-req "GET" "/" {})))
+(dream-dm-test
+  "counter first visit"
+  (dream-resp-body dream-dm-c1)
+  "<p>You have visited this page 1 time(s).</p>")
+(dream-dm-test
+  "counter sets cookie"
+  (len (dream-resp-cookies dream-dm-c1))
+  1)
+
+;; subsequent visits with the cookie increment
+(dream-dm-test
+  "counter second visit"
+  (dream-resp-body (dream-dm-capp (dream-dm-req "GET" "/" {:Cookie "dream.session=s1"})))
+  "<p>You have visited this page 2 time(s).</p>")
+(dream-dm-test
+  "counter third visit"
+  (dream-resp-body (dream-dm-capp (dream-dm-req "GET" "/" {:Cookie "dream.session=s1"})))
+  "<p>You have visited this page 3 time(s).</p>")
+
+;; reset zeroes the counter then redirects
+(define
+  dream-dm-reset
+  (dream-dm-capp (dream-dm-req "POST" "/reset" {:Cookie "dream.session=s1"})))
+(dream-dm-test
+  "counter reset redirects"
+  (dream-status dream-dm-reset)
+  303)
+(dream-dm-test
+  "counter after reset"
+  (dream-resp-body (dream-dm-capp (dream-dm-req "GET" "/" {:Cookie "dream.session=s1"})))
+  "<p>You have visited this page 1 time(s).</p>")
+
+;; a different session is independent
+(dream-dm-test
+  "counter distinct session"
+  (dream-resp-body (dream-dm-capp (dream-dm-req "GET" "/" {})))
+  "<p>You have visited this page 1 time(s).</p>")
+
+(define dream-dm-tests-run! (fn () {:total (+ dream-dm-pass dream-dm-fail) :passed dream-dm-pass :failed dream-dm-fail :fails dream-dm-fails}))

plans/dream-on-sx.md

@@ -74,11 +74,11 @@ The five types: `request`, `response`, `handler = request -> response`, `middlew
       - `dream-send ws msg`, `dream-receive ws`, `dream-close ws`.
 - [x] **Static files:** `dream-static root-path` — serves files, ETags, range requests.
 - [x] **`dream-run`**: wires root handler into SX's `perform (:http-listen ...)`.
-- [ ] **Demos** in `lib/dream/demos/`:
-      - `hello.ml` → `lib/dream/demos/hello.sx`: "Hello, World!" route.
-      - `counter.ml` → `lib/dream/demos/counter.sx`: in-memory counter with sessions.
-      - `chat.ml` → `lib/dream/demos/chat.sx`: multi-room WebSocket chat.
-      - `todo.ml` → `lib/dream/demos/todo.sx`: CRUD list with forms + CSRF.
+- [~] **Demos** in `lib/dream/demos/`:
+      - [x] `hello.ml` → `lib/dream/demos/hello.sx`: "Hello, World!" route.
+      - [x] `counter.ml` → `lib/dream/demos/counter.sx`: in-memory counter with sessions.
+      - [ ] `chat.ml` → `lib/dream/demos/chat.sx`: multi-room WebSocket chat.
+      - [ ] `todo.ml` → `lib/dream/demos/todo.sx`: CRUD list with forms + CSRF.
 - [ ] Tests in `lib/dream/tests/`: routing dispatch, middleware composition, session round-trip, CSRF accept/reject, flash read-after-write — 60+ tests.
 
 ## Stdlib additions Dream will need
@@ -198,6 +198,11 @@ Confirm scope before starting; some of these may be addable as Dream-internal he
   set-cookies (from session/flash) flow through. Listen transport injectable
   (`dream-run-with`) so the full wiring is tested with a mock that captures the op and
   re-runs the captured app. `dream-run-port` / `dream-run-opts` variants.
+- **2026-06-07 — Demos: hello + counter** (`lib/dream/demos/`, 10 tests). `hello.sx`
+  is the canonical router with a `:name` param route. `counter.sx` is a per-session
+  visit counter on the session middleware (+ a `/reset` POST that redirects),
+  demonstrating session isolation across browsers. End-to-end tests drive both apps
+  as the host would. chat (ws) + todo (forms+CSRF) next.
 
 ## Blockers