dream: forms (urlencoded) + stateless signed CSRF + 26 tests

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

lib/dream/tests/form.sx

@@ -0,0 +1,181 @@
+;; lib/dream/tests/form.sx — urlencoded parsing, Ok/Err, CSRF accept/reject.
+
+(define dream-fo-pass 0)
+(define dream-fo-fail 0)
+(define dream-fo-fails (list))
+
+(define
+  dream-fo-test
+  (fn
+    (name actual expected)
+    (if
+      (= actual expected)
+      (set! dream-fo-pass (+ dream-fo-pass 1))
+      (begin
+        (set! dream-fo-fail (+ dream-fo-fail 1))
+        (append! dream-fo-fails {:name name :actual actual :expected expected})))))
+
+;; ── Result ─────────────────────────────────────────────────────────
+(dream-fo-test "ok? on ok" (dream-ok? (dream-ok 5)) true)
+(dream-fo-test "err? on ok" (dream-err? (dream-ok 5)) false)
+(dream-fo-test "ok value" (dream-ok-value (dream-ok {:a 1})) {:a 1})
+(dream-fo-test "err reason" (dream-err-reason (dream-err :bad)) "bad")
+
+;; ── urlencoded parsing ─────────────────────────────────────────────
+(define
+  dream-fo-req
+  (fn (body) (dream-request "POST" "/f" {:Content-Type "application/x-www-form-urlencoded"} body)))
+
+(dream-fo-test
+  "parse two fields"
+  (dream-form-fields (dream-fo-req "a=1&b=2"))
+  {:a "1" :b "2"})
+(dream-fo-test
+  "url-decoded value"
+  (dream-form-field (dream-fo-req "name=Ada+Lovelace") "name")
+  "Ada Lovelace")
+(dream-fo-test
+  "percent decode"
+  (dream-form-field (dream-fo-req "x=a%20b%21") "x")
+  "a b!")
+(dream-fo-test "empty body" (dream-form-fields (dream-fo-req "")) {})
+(dream-fo-test
+  "valueless key"
+  (dream-form-field (dream-fo-req "flag") "flag")
+  "")
+(dream-fo-test
+  "decoded key"
+  (dream-form-field (dream-fo-req "first%20name=x") "first name")
+  "x")
+
+;; ── CSRF sign + verify ─────────────────────────────────────────────
+(dream-fo-test
+  "sign deterministic"
+  (=
+    (dream-csrf-sign-default "secret" "s1")
+    (dream-csrf-sign-default "secret" "s1"))
+  true)
+(dream-fo-test
+  "sign secret-sensitive"
+  (=
+    (dream-csrf-sign-default "secret" "s1")
+    (dream-csrf-sign-default "other" "s1"))
+  false)
+(dream-fo-test
+  "sign session-sensitive"
+  (=
+    (dream-csrf-sign-default "secret" "s1")
+    (dream-csrf-sign-default "secret" "s2"))
+  false)
+(dream-fo-test
+  "token valid for own session"
+  (dr/csrf-valid?
+    dream-csrf-sign-default
+    "k"
+    "s1"
+    (dr/csrf-make-token dream-csrf-sign-default "k" "s1"))
+  true)
+(dream-fo-test
+  "token invalid for other session"
+  (dr/csrf-valid?
+    dream-csrf-sign-default
+    "k"
+    "s2"
+    (dr/csrf-make-token dream-csrf-sign-default "k" "s1"))
+  false)
+(dream-fo-test
+  "tampered token invalid"
+  (dr/csrf-valid? dream-csrf-sign-default "k" "s1" "s1.deadbeef")
+  false)
+(dream-fo-test
+  "empty token invalid"
+  (dr/csrf-valid? dream-csrf-sign-default "k" "s1" "")
+  false)
+(dream-fo-test
+  "nil token invalid"
+  (dr/csrf-valid? dream-csrf-sign-default "k" "s1" nil)
+  false)
+
+;; ── full stack: session -> csrf -> handler ─────────────────────────
+(define dream-fo-backend (dream-memory-sessions))
+(define dream-fo-sid (dream-fo-backend {:op "session/create"}))   ;; s1
+
+;; build a request already carrying the session cookie + csrf middleware applied
+(define
+  dream-fo-stack
+  (fn
+    (handler)
+    ((dream-sessions dream-fo-backend) ((dream-csrf "topsecret") handler))))
+
+;; a handler that emits its csrf tag
+(define
+  dream-fo-tag-out
+  (dream-resp-body
+    ((dream-fo-stack (fn (req) (dream-text (dream-csrf-tag req))))
+      (dream-request "GET" "/form" {:Cookie "dream.session=s1"} ""))))
+(dream-fo-test
+  "csrf-tag is hidden input"
+  (contains? dream-fo-tag-out "type=\"hidden\"")
+  true)
+(dream-fo-test
+  "csrf-tag names field"
+  (contains? dream-fo-tag-out "name=\"dream.csrf\"")
+  true)
+
+;; valid token (signed for s1) -> dream-form Ok
+(define
+  dream-fo-good-token
+  (dr/csrf-make-token dream-csrf-sign-default "topsecret" "s1"))
+(define
+  dream-fo-submit
+  (fn
+    (token)
+    ((dream-fo-stack (fn (req) (let ((r (dream-form req))) (if (dream-ok? r) (dream-text (str "ok:" (get (dream-ok-value r) "msg"))) (dream-text (str "err:" (dream-err-reason r)))))))
+      (dream-request
+        "POST"
+        "/form"
+        {:Cookie "dream.session=s1"}
+        (str "msg=hello&dream.csrf=" token)))))
+
+(dream-fo-test
+  "valid csrf -> Ok fields"
+  (dream-resp-body (dream-fo-submit dream-fo-good-token))
+  "ok:hello")
+(dream-fo-test
+  "bad csrf -> Err"
+  (dream-resp-body (dream-fo-submit "s1.wrong"))
+  "err:csrf-token-invalid")
+(dream-fo-test
+  "missing csrf -> Err"
+  (dream-resp-body (dream-fo-submit ""))
+  "err:csrf-token-invalid")
+
+;; ── csrf-protect middleware auto-rejects ───────────────────────────
+(define
+  dream-fo-protected
+  (fn
+    (handler)
+    ((dream-sessions dream-fo-backend)
+      ((dream-csrf-protect "topsecret") handler))))
+(define dream-fo-ph (dream-fo-protected (fn (req) (dream-text "reached"))))
+
+(dream-fo-test
+  "GET passes without token"
+  (dream-resp-body (dream-fo-ph (dream-request "GET" "/x" {:Cookie "dream.session=s1"} "")))
+  "reached")
+(dream-fo-test
+  "POST without token 403"
+  (dream-status (dream-fo-ph (dream-request "POST" "/x" {:Cookie "dream.session=s1"} "")))
+  403)
+(dream-fo-test
+  "POST with valid token reaches"
+  (dream-resp-body
+    (dream-fo-ph
+      (dream-request
+        "POST"
+        "/x"
+        {:Cookie "dream.session=s1"}
+        (str "dream.csrf=" dream-fo-good-token))))
+  "reached")
+
+(define dream-fo-tests-run! (fn () {:total (+ dream-fo-pass dream-fo-fail) :passed dream-fo-pass :failed dream-fo-fail :fails dream-fo-fails}))