From f7a7b725ef633b4802382e86143406e43954d506 Mon Sep 17 00:00:00 2001
From: Alice Grosch <a.grosch@fz-juelich.de>
Date: Fri, 2 Jun 2023 13:13:33 +0200
Subject: [PATCH] Allow use of function via custom_port variable

---
 backendspawner/backendspawner.py | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/backendspawner/backendspawner.py b/backendspawner/backendspawner.py
index 814e682..9313149 100644
--- a/backendspawner/backendspawner.py
+++ b/backendspawner/backendspawner.py
@@ -92,13 +92,26 @@ def get_request_kwargs(self):
             request_kwargs = self.request_kwargs
         return request_kwargs
 
-    port = Union(
+    custom_port = Union(
         [Integer(), Callable()],
         default_value=8080,
         help="""
         """,
     ).tag(config=True)
 
+    port = Integer(
+        help="""
+        The port for single-user servers to listen on.
+        """,
+    )
+
+    @default('port')
+    def get_port(self):
+        port = self.custom_port
+        if callable(port):
+            port = port()
+        return port
+
     async def get_port(self):
         if callable(self.port):
             port = await maybe_future(self.port(self))