Incorporate suggestions following C/R

- Use testutil.create_tempfile to create temporary file
- Use a smaller file, 8 MiB is enough to simulate the issu
- Use monkeypatch.setattr() to modify global values for test_delete_conflict test
- Use time.sleep() instead of reading one byte

test/handlers/tickets_test.py

@@ -3,6 +3,7 @@
 
 import http.client as http_client
 import json
+import time
 import uuid
 
 import pytest
@@ -399,24 +400,22 @@ def test_delete_all(srv):
         pytest.raises(KeyError, srv.auth.get, ticket["uuid"])
 
 
-def test_delete_active_connection(srv, tmpdir):
-    # Use short timeout to keep the tests fast.
-    srv.config.control.remove_timeout = 0.0001
-
-    filename = tmpdir.join("image")
-    # Note: must be big enough so the request remain active.
-    size = 1024**3 * 100
-    with open(str(filename), 'wb') as image:
-        image.truncate(size)
-    ticket = testutil.create_ticket(
-        url="file://" + str(filename), ops=["read"], size=size)
+def test_delete_conflict(srv, tmpdir, monkeypatch):
+    image = testutil.create_tempfile(tmpdir, "image", size=8 * 1024**2)
+    ticket = testutil.create_ticket(url="file://" + str(image))
     srv.auth.add(ticket)
 
-    with http.ControlClient(srv.config) as c:
-        # Start a download, but read only 1 byte to make sure the operation
-        # becomes active but do not complete.
-        with http.RemoteClient(srv.config) as con:
-            remoteimage = con.get("/images/%(uuid)s" % ticket)
-            remoteimage.read(1)
-            res = c.delete("/tickets/%(uuid)s" % ticket)
+    # Use very short timeout to make the test fast.
+    monkeypatch.setattr(srv.config.control, "remove_timeout", 0.001)
+
+    with http.RemoteClient(srv.config) as remote_client:
+        remote_client.get("/images/" + ticket["uuid"])
+
+        # Wait enough time to get the server connnection thread block on the
+        # client socket trying to write more data.
+        time.sleep(0.1)
+
+        with http.ControlClient(srv.config) as control_client:
+            res = control_client.delete("/tickets/" + ticket["uuid"])
+            res.read()
             assert res.status == 409