test: the lab prints from a signed-in lesson, and judges black and white on the job

A lesson site for the lab (session cookie, one-time addresses, a second origin, a request log) and real right-clicks on its words and on a JPEG, a PNG, a transparent PNG, a one-time picture, another site's, a blob:, a WebP, a canvas, a linked picture, a broken one, and Cancel. Each is judged on the job CUPS kept — where and how large, no other ink — and on the site log: nothing was fetched again. The clipboard is the teacher's afterwards. Black and white: a colourful lesson turned back and forth five times on page 2, a worksheet, a picture at 50% top left, a page full of pictures, back to Color, and Cancel. Every grey preview is grey pixel for pixel and the job is byte-for-byte the file shown, through pxlmono. The three 0.2.6.2 black-and-white scenarios now wait for the grey file before Print, as a teacher has to. 343 checks, none failing. Co-Authored-By: Claude Opus 5.5 <[email protected]>
2026-09-26 16:34:38 -05:00
parent 594fbd810e
commit cb12e59dea
4 changed files with 535 additions and 35 deletions
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+"""A signed-in lesson with pictures in it, for right-click printing.
+
+    wonderink-lesson-site.py PICTURES PORT OTHER_PORT LOG
+
+Run inside the lab by tools/lab/wonderink-print-check. Stands in for
+Wonder Ink's own site, which the lab has no account for, with every kind
+of picture a lesson might put under a teacher's pointer:
+
+    /login          sets a session cookie (HttpOnly, SameSite=Lax), as a
+                    sign-in does, and goes on to /lesson
+    /lesson         the page; its pictures are all behind that cookie
+    /private/NAME   a picture, 403 without the cookie
+    /once/N/NAME    a picture that can be fetched exactly once — so a
+                    print that fetches it again gets a 404, not a picture
+    OTHER_PORT      the same pictures from another origin, with no CORS
+
+Every request is logged, one JSON line each, so a check can say what was
+fetched while it printed. What was measured with this, and why Print
+image fetches nothing, is in classroom-wonderink's _take_picture.
+"""
+
+import http.server
+import json
+import sys
+import threading
+import time
+import uuid
+from pathlib import Path
+from urllib.parse import urlparse
+
+PICTURES = Path(sys.argv[1])
+PORT, OTHER = int(sys.argv[2]), int(sys.argv[3])
+LOG = Path(sys.argv[4])
+TYPES = {".png": "image/png", ".jpg": "image/jpeg", ".webp": "image/webp"}
+fetched_once = set()
+lock = threading.Lock()
+
+LESSON = """<html><head><title>Picture lesson</title><style>
+body { margin: 8px; font: 15px sans-serif; }
+img, canvas { width: 180px; height: 120px; object-fit: contain; border: 1px solid #ccc; margin: 4px; }
+</style></head><body>
+<h1 style="color:#c00">Noah's Ark</h1>
+<p id="words">Noah built an ark, and the animals came two by two. Colour the pictures below.</p>
+<img id="private-jpg" src="/private/ark-wide.jpg">
+<img id="private-png" src="/private/ark-tall.png">
+<img id="clear" src="/private/ark-clear.png">
+<img id="webp" src="/private/ark-wide.webp">
+<img id="once" src="/once/NONCE/ark-wide.png">
+<img id="cross" src="http://localhost:OTHER/img/ark-tall.png">
+<img id="blob">
+<canvas id="canvas" width="1600" height="1000"></canvas>
+<img id="broken" src="/private/not-there.png">
+<a href="/lesson#more"><img id="linked" src="/private/ark-tall.png"></a>
+<script>
+var waiting = 2;
+function one() { if (--waiting === 0) window.__ready = true; }
+fetch('/private/ark-tall.png', {credentials: 'include'})
+  .then(function (r) { return r.blob(); })
+  .then(function (b) { var i = document.getElementById('blob'); i.onload = one; i.src = URL.createObjectURL(b); });
+var art = new Image();
+art.onload = function () { document.getElementById('canvas').getContext('2d').drawImage(art, 0, 0); one(); };
+art.src = '/private/ark-wide.png';
+</script></body></html>"""
+
+
+class Handler(http.server.BaseHTTPRequestHandler):
+    def log_message(self, *_):
+        pass
+
+    def answer(self, code, body=b"", kind="text/plain", headers=()):
+        self.send_response(code)
+        self.send_header("Content-Type", kind)
+        self.send_header("Content-Length", str(len(body)))
+        for name, value in headers:
+            self.send_header(name, value)
+        self.end_headers()
+        self.wfile.write(body)
+
+    def picture(self, name):
+        path = PICTURES / Path(name).name
+        if not path.is_file() or path.suffix not in TYPES:
+            return self.answer(404, b"no such picture")
+        return self.answer(200, path.read_bytes(), TYPES[path.suffix],
+                           [("Cache-Control", "private, max-age=600")])
+
+    def do_GET(self):
+        path = urlparse(self.path).path
+        signed_in = "session=ok" in self.headers.get("Cookie", "")
+
+        with lock, open(LOG, "a") as log:
+            log.write(json.dumps({"t": time.time(), "port": self.server.server_port,
+                                  "path": path, "signed_in": signed_in}) + "\n")
+
+        if self.server.server_port == OTHER:
+            if path.startswith("/img/"):
+                return self.picture(path[5:])
+            return self.answer(404)
+
+        if path == "/login":
+            return self.answer(302, headers=[
+                ("Set-Cookie", "session=ok; Path=/; HttpOnly; SameSite=Lax"),
+                ("Location", "/lesson")])
+
+        if not signed_in:
+            return self.answer(403, b"sign in first")
+
+        if path == "/lesson":
+            page = LESSON.replace("NONCE", uuid.uuid4().hex).replace("OTHER", str(OTHER))
+            return self.answer(200, page.encode(), "text/html")
+
+        if path.startswith("/private/"):
+            return self.picture(path[9:])
+
+        if path.startswith("/once/"):
+            with lock:
+                if path in fetched_once:
+                    return self.answer(404, b"this address has been used")
+                fetched_once.add(path)
+            return self.picture(path.rsplit("/", 1)[1])
+
+        return self.answer(404)
+
+
+for port in (OTHER, PORT):
+    server = http.server.ThreadingHTTPServer(("127.0.0.1", port), Handler)
+    threading.Thread(target=server.serve_forever, daemon=True).start()
+
+threading.Event().wait()