Handle reading of RC response via stdin

kitty/boss.py

@@ -130,7 +130,7 @@ class Boss:
         if self.opts.allow_remote_control:
             pass
         else:
-            response = {'ok': False, 'err': 'NOT_ALLOWED'}
+            response = {'ok': False, 'error': 'Remote control is disabled. Add allow_remote_control yes to your kitty.conf'}
         if response is not None:
             if window is not None:
                 window.send_cmd_response(response)

kitty/remote_control.py

@@ -3,11 +3,13 @@
 # License: GPL v3 Copyright: 2018, Kovid Goyal <kovid at kovidgoyal.net>
 
 import json
+import re
 import sys
 from functools import partial
 
 from kitty.cli import emph, parse_args
 from kitty.constants import appname, version
+from kitty.utils import read_with_timeout
 
 
 def cmd(short_desc, desc=None, options_spec=None):
@@ -36,6 +38,30 @@ global_options_spec = partial('''\
 '''.format, appname=appname)
 
 
+def read_from_stdin(send):
+    send = ('@kitty-cmd' + json.dumps(send)).encode('ascii')
+    if not sys.stdout.isatty():
+        raise SystemExit('stdout is not a terminal')
+    sys.stdout.buffer.write(b'\x1bP' + send + b'\x1b\\')
+    sys.stdout.flush()
+
+    received = b''
+    dcs = re.compile(br'\x1bP@kitty-cmd([^\x1b]+)\x1b\\')
+    match = None
+
+    def more_needed(data):
+        nonlocal received, match
+        received += data
+        match = dcs.search(received)
+        return match is None
+
+    read_with_timeout(more_needed)
+    if match is None:
+        raise SystemExit('Failed to receive response from ' + appname)
+    response = json.loads(match.group(1).decode('ascii'))
+    return response
+
+
 def main(args):
     cmap = {k[4:]: v for k, v in globals().items() if k.startswith('cmd_')}
     all_commands = tuple(sorted(cmap))
@@ -66,8 +92,8 @@ def main(args):
     }
     if payload is not None:
         send['payload'] = payload
-    send = ('@kitty-cmd' + json.dumps(send)).encode('ascii')
-    if not sys.stdout.isatty():
-        raise SystemExit('stdout is not a terminal')
-    sys.stdout.buffer.write(b'\x1bP' + send + b'\x1b\\')
-    sys.stdout.flush()
+    response = read_from_stdin(send)
+    if not response.get('ok'):
+        if response.get('tb'):
+            print(response['tb'], file=sys.stderr)
+        raise SystemExit(response['error'])