Allow port to be changed using MTT_PORT environment variable.

tests/step_defs/server.py

@@ -2,6 +2,8 @@
 
 from asyncio import create_subprocess_exec, get_event_loop, sleep
 from pathlib import Path
+from socket import socket
+
 
 class Server:
     """Setup a single server."""
@@ -36,13 +38,14 @@ class Server:
     @port.setter
     def port(self, num):
         """Set the port for the server."""
-        self.env["MTT_PORT"] = num
+        self.env["MTT_PORT"] = str(num)
 
     async def __start(self):
         """async start of the server."""
+        print(self.env)
         self.process = await create_subprocess_exec(
-                Path.cwd().joinpath("target", "release", "morethantext_web")
-                )
+            Path.cwd().joinpath("target", "release", "morethantext_web"), env=self.env
+        )
         await sleep(1)
 
     async def __stop(self):
@@ -62,3 +65,10 @@ class Server:
     def destroy(self):
         """Removes the server instance."""
         self.stop()
+
+    def set_safe_port(self):
+        """Set the server port to something not being used."""
+        sock = socket()
+        sock.bind((self.address, 0))
+        self.port = sock.getsockname()[1]
+        sock.close()