Merge pull request #8 from digital-asset/python-optional-sigint-handler

python: Make both SIGINT and SIGQUIT handlers optional.

VERSION

@@ -1 +1 @@
-5.6.4
+5.6.5

python/dazl/client/api.py

@@ -216,11 +216,11 @@ def start_in_background(
         run_state = RunState(RunLevel.RUN_FOREVER)
         if install_signal_handlers:
             # the main loop will be run from a background thread, so do NOT use asyncio directly
-            signal.signal(signal.SIGINT, lambda *_: self._impl.shutdown())
             try:
-                signal.signal(signal.SIGINT, lambda *_: self._impl.abort())
-            except ValueError:
-                # SIGQUIT is not supported on Windows.
+                signal.signal(signal.SIGINT, lambda *_: self._impl.shutdown())
+                signal.signal(signal.SIGQUIT, lambda *_: self._impl.abort())
+            except (NotImplementedError, AttributeError, ValueError):
+                # SIGINIT and SIGQUIT handlers are not supported on Windows.
                 pass
 
         return self._impl.start(run_state, daemon)
@@ -259,11 +259,11 @@ def _run(self, initial_run_level, *coroutines: Awaitable[None],
         run_state = RunState(initial_run_level)
         loop = get_event_loop()
         if install_signal_handlers:
-            loop.add_signal_handler(signal.SIGINT, run_state.handle_sigint)
             try:
+                loop.add_signal_handler(signal.SIGINT, run_state.handle_sigint)
                 loop.add_signal_handler(signal.SIGQUIT, run_state.handle_sigquit)
-            except ValueError:
-                # SIGQUIT is not supported on Windows.
+            except (NotImplementedError, AttributeError, ValueError):
+                # SIGINT and SIGQUIT are not supported on Windows.
                 pass
 
         loop.run_until_complete(self.aio_run(*coroutines, run_state=run_state))

python/dazl/util/termcap.py

@@ -9,13 +9,16 @@
 from typing import Optional, Tuple
 
 
-def termsize() -> Tuple[Optional[int], Optional[int]]:
+def termsize() -> 'Tuple[Optional[int], Optional[int]]':
     """
     Return the current size of the terminal. If the current terminal is not a tty, then
     ``(None, None)`` is returned.
     """
-    with Popen(['stty', 'size'], stdout=PIPE, stderr=DEVNULL) as proc:
-        term_size_str = proc.stdout.read().decode('utf8')
+    try:
+        with Popen(['stty', 'size'], stdout=PIPE, stderr=DEVNULL) as proc:
+            term_size_str = proc.stdout.read().decode('utf8')
+    except FileNotFoundError:
+        term_size_str = None
     if term_size_str is not None:
         dimensions = term_size_str.split()
         if len(dimensions) >= 2:

python/pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "dazl"
-version = "5.6.4"
+version = "5.6.5"
 description = "high-level Ledger API client for DAML ledgers"
 license = "Apache-2.0"
 authors = ["Davin K. Tanabe <davin.tanabe@digitalasset.com>"]