Split TaskStatusService connection and post

This commit will move establishment of status service connection from
post method to its own dedicated method. Thanks to this change, it will
be possible to establish connection over again when a problem occurs.

Signed-off-by: Jan Richter <[email protected]>

avocado/core/nrunner/task.py

@@ -40,27 +40,35 @@ class TaskStatusService:
 
     def __init__(self, uri):
         self.uri = uri
-        self.connection = None
+        self._connection = None
 
-    def post(self, status):
+    @property
+    def connection(self):
+        if not self._connection:
+            self._create_connection()
+        return self._connection
+
+    def _create_connection(self):
+        """
+        Creates connection with `self.uri` based on `socket.create_connection`
+        """
         if ":" in self.uri:
             host, port = self.uri.split(":")
             port = int(port)
-            if self.connection is None:
-                for _ in range(600):
-                    try:
-                        self.connection = socket.create_connection((host, port))
-                        break
-                    except ConnectionRefusedError as error:
-                        LOG.warning(error)
-                        time.sleep(1)
-                else:
-                    self.connection = socket.create_connection((host, port))
+            for _ in range(600):
+                try:
+                    self._connection = socket.create_connection((host, port))
+                    break
+                except ConnectionRefusedError as error:
+                    LOG.warning(error)
+                    time.sleep(1)
+            else:
+                self._connection = socket.create_connection((host, port))
         else:
-            if self.connection is None:
-                self.connection = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
-                self.connection.connect(self.uri)
+            self._connection = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+            self._connection.connect(self.uri)
 
+    def post(self, status):
         data = json_dumps(status)
         self.connection.send(data.encode("ascii") + "\n".encode("ascii"))