Kokkoja as of 2026-10-10: the teacher's requests, the Session window, notices, the QR code, the license

kokkoja.py

@@ -106,6 +106,31 @@ def load_token(directory):
     return token
 
 
+def remembered_relay(directory, given=""):
+    """The relay to use: the one given, which is then remembered in the
+    configuration directory, or else the one remembered from last time.
+
+    Returns (address, remembered): the address, or None if none was given
+    and none is remembered, and whether it came from memory.  A relay
+    address is typed once; afterwards the program is started bare (Andy,
+    2026-10-08, after a start without --relay sent an invitation to a
+    relay on his own computer that was not running).
+    """
+    path = directory / "relay"
+    if given:
+        given = given.strip()
+        directory.mkdir(parents=True, exist_ok=True)
+        if path.exists() and path.read_text().strip() == given:
+            return given, False
+        write_atomically(path, (given + "\n").encode())
+        return given, False
+    try:
+        kept = path.read_text().strip()
+    except OSError:
+        kept = ""
+    return (kept, True) if kept else (None, False)
+
+
 def write_atomically(path, data):
     """Replace a file so that it is never seen half written."""
     temporary = path.with_name("." + path.name + ".writing")
@@ -132,7 +157,8 @@ def keep_page(notebook):
         changed = current.stat().st_mtime
     except FileNotFoundError:
         return None, False
-    if b"data-stroke=" not in data and b"<image" not in data:
+    # Blank: no stroke, no text block, no image.
+    if not any(mark in data for mark in (b"data-stroke=", b"data-text=", b"<image")):
         return None, False
 
     kept = [entry for entry in notebook.iterdir()
@@ -459,9 +485,10 @@ def make_server(port, relay, notebooks, token, config, site=""):
 def main():
     parser = argparse.ArgumentParser(description="Kokkoja local program")
     parser.add_argument("--port", type=int, default=8760)
-    parser.add_argument("--relay", default="ws://127.0.0.1:8770",
-                        help="relay used for sessions started here "
-                             "(default ws://127.0.0.1:8770)")
+    parser.add_argument("--relay", default="",
+                        help="relay used for sessions started here, such as "
+                             "wss://kokkoja.example/relay; remembered, so it "
+                             "need be given only once")
     parser.add_argument("--site", default="",
                         help="Kokkoja web site that invitations link to, so that "
                              "guests can join with nothing installed (default: "
@@ -478,10 +505,16 @@ def main():
 
     notebooks = arguments.notebooks or default_notebooks_directory()
     config = arguments.config or config_directory()
+    relay, remembered = remembered_relay(config, arguments.relay)
+    if relay is None:
+        parser.exit(2, "Kokkoja needs the address of a relay the first time it is started:\n"
+                       "    python3 kokkoja.py --relay wss://kokkoja.example/relay\n"
+                       "Afterwards the address is remembered and python3 kokkoja.py is enough.\n")
     token = load_token(config)
-    server = make_server(arguments.port, arguments.relay, notebooks, token, config, arguments.site)
+    server = make_server(arguments.port, relay, notebooks, token, config, arguments.site)
     address = f"http://localhost:{arguments.port}/#token={token}"
     print(f"Kokkoja is at {address}", flush=True)
+    print(f"Relay: {relay}" + (" (remembered from last time)" if remembered else ""), flush=True)
     print(f"Notebooks are in {notebooks}", flush=True)
     print("Ctrl-C to stop.", flush=True)
     if not arguments.no_browser: