python/qemu/console_socket.py: Add type hint annotations

Finish the typing of console_socket.py with annotations and no code
changes.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-16-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>

python/qemu/console_socket.py

@@ -17,7 +17,7 @@ from collections import deque
 import socket
 import threading
 import time
-from typing import Optional
+from typing import Deque, Optional
 
 
 class ConsoleSocket(socket.socket):
@@ -30,11 +30,11 @@ class ConsoleSocket(socket.socket):
     Optionally a file path can be passed in and we will also
     dump the characters to this file for debugging purposes.
     """
-    def __init__(self, address, file=None, drain=False):
-        self._recv_timeout_sec = 300
+    def __init__(self, address: str, file: Optional[str] = None,
+                 drain: bool = False):
         self._recv_timeout_sec = 300.0
         self._sleep_time = 0.5
-        self._buffer = deque()
+        self._buffer: Deque[str] = deque()
         socket.socket.__init__(self, socket.AF_UNIX, socket.SOCK_STREAM)
         self.connect(address)
         self._logfile = None
@@ -45,7 +45,7 @@ class ConsoleSocket(socket.socket):
         if drain:
             self._drain_thread = self._thread_start()
 
-    def _drain_fn(self):
+    def _drain_fn(self) -> None:
         """Drains the socket and runs while the socket is open."""
         while self._open:
             try:
@@ -56,7 +56,7 @@ class ConsoleSocket(socket.socket):
                 # self._open is set to False.
                 time.sleep(self._sleep_time)
 
-    def _thread_start(self):
+    def _thread_start(self) -> threading.Thread:
         """Kick off a thread to drain the socket."""
         # Configure socket to not block and timeout.
         # This allows our drain thread to not block
@@ -68,7 +68,7 @@ class ConsoleSocket(socket.socket):
         drain_thread.start()
         return drain_thread
 
-    def close(self):
+    def close(self) -> None:
         """Close the base object and wait for the thread to terminate"""
         if self._open:
             self._open = False
@@ -80,7 +80,7 @@ class ConsoleSocket(socket.socket):
                 self._logfile.close()
                 self._logfile = None
 
-    def _drain_socket(self):
+    def _drain_socket(self) -> None:
         """process arriving characters into in memory _buffer"""
         data = socket.socket.recv(self, 1)
         # latin1 is needed since there are some chars
@@ -114,7 +114,7 @@ class ConsoleSocket(socket.socket):
         # socket w/o our intervention.
         return chars.encode("latin1")
 
-    def setblocking(self, value):
+    def setblocking(self, value: bool) -> None:
         """When not draining we pass thru to the socket,
            since when draining we control socket blocking.
         """