with help/side-comments from alex i fixed the concurrent account creation problem

chatmaild/pyproject.toml

@@ -15,6 +15,9 @@ filtermail = "chatmaild.filtermail:main"
 
 [tool.pytest.ini_options]
 addopts = "-v -ra --strict-markers"
+log_format = "%(asctime)s %(levelname)s %(message)s"
+log_date_format = "%Y-%m-%d %H:%M:%S"
+log_level = "INFO"
 
 [tool.tox]
 legacy_tox_ini = """

chatmaild/src/chatmaild/doveauth.py

@@ -116,7 +116,7 @@ def handle_dovecot_request(msg, db, mail_domain):
 
 
 class ThreadedUnixStreamServer(ThreadingMixIn, UnixStreamServer):
-    pass
+    request_queue_size = 100
 
 
 def main():
@@ -128,14 +128,20 @@ def main():
 
     class Handler(StreamRequestHandler):
         def handle(self):
-            while True:
-                msg = self.rfile.readline().strip().decode()
-                if not msg:
-                    break
-                res = handle_dovecot_request(msg, db, mail_domain)
-                if res:
-                    self.wfile.write(res.encode("ascii"))
-                    self.wfile.flush()
+            try:
+                while True:
+                    msg = self.rfile.readline().strip().decode()
+                    if not msg:
+                        break
+                    res = handle_dovecot_request(msg, db, mail_domain)
+                    if res:
+                        self.wfile.write(res.encode("ascii"))
+                        self.wfile.flush()
+                    else:
+                        logging.warn("request had no answer: %r", msg)
+            except Exception:
+                logging.exception()
+                raise
 
     try:
         os.unlink(socket)

tests/chatmaild/test_doveauth.py

@@ -1,5 +1,5 @@
 import json
-
+import sys
 import pytest
 import threading
 import queue
@@ -60,27 +60,31 @@ def test_handle_dovecot_request(db):
     assert userdata["password"].startswith("{SHA512-CRYPT}")
 
 
-def test_100_concurrent_lookups(db):
-    num = 100
-    dbs = [Database(db.path) for i in range(num)]
-    print(f"created {num} databases")
+def test_100_concurrent_lookups_different_accounts(db, gencreds):
+    num_threads = 100
+    req_per_thread = 5
     results = queue.Queue()
 
     def lookup(db):
-        try:
-            lookup_passdb(db, "something@c1.testrun.org", "Pieg9aeToe3eghuthe5u")
-        except Exception:
-            results.put(traceback.format_exc())
-        else:
-            results.put(None)
+        for i in range(req_per_thread):
+            addr, password = gencreds()
+            try:
+                lookup_passdb(db, addr, password)
+            except Exception:
+                results.put(traceback.format_exc())
+            else:
+                results.put(None)
 
-    threads = [threading.Thread(target=lookup, args=(db,), daemon=True) for db in dbs]
+    threads = []
+    for i in range(num_threads):
+        thread = threading.Thread(target=lookup, args=(db,), daemon=True)
+        threads.append(thread)
 
-    print(f"created {num} threads, starting them and waiting for results")
+    print(f"created {num_threads} threads, starting them and waiting for results")
     for thread in threads:
         thread.start()
 
-    for _ in dbs:
+    for i in range(num_threads * req_per_thread):
         res = results.get()
         if res is not None:
             pytest.fail(f"concurrent lookup failed\n{res}")