Released 1.7.1

The biggest issue was the construction of an asyncio.Semaphore() while the
default loop is alive, and then creating a new loop on win32.

I've also taken the opportunity to explicitly pass our loop to some calls,
rather than expecting them to use the correct one automagically, and added
some more explicit timeout handling to the semaphore usage.

CHANGELOG.md

@@ -1,6 +1,11 @@
 # Blender Cloud changelog
 
 
+## Version 1.7.1 (2017-06-13)
+
+- Fixed asyncio issues on Windows
+
+
 ## Version 1.7.0 (2017-06-09)
 
 - Fixed reloading after upgrading from 1.4.4 (our last public release).
@@ -10,7 +15,7 @@
 
 ## Version 1.6.4 (2017-04-21)
 
-- Added file exclusion filter for Flamenco. A filter like "*.abc;*.mkv;*.mov" can be
+- Added file exclusion filter for Flamenco. A filter like `*.abc;*.mkv;*.mov` can be
   used to prevent certain files from being copied to the job storage directory.
   Requires a Blender that is bundled with BAM 1.1.7 or newer.
 

blender_cloud/__init__.py

@@ -21,7 +21,7 @@
 bl_info = {
     'name': 'Blender Cloud',
     "author": "Sybren A. Stüvel, Francesco Siddi, Inês Almeida, Antony Riakiotakis",
-    'version': (1, 7, 0),
+    'version': (1, 7, 1),
     'blender': (2, 77, 0),
     'location': 'Addon Preferences panel, and Ctrl+Shift+Alt+A anywhere for texture browser',
     'description': 'Texture library browser and Blender Sync. Requires the Blender ID addon '

blender_cloud/async_loop.py

@@ -33,17 +33,12 @@ _loop_kicking_operator_running = False
 
 
 def setup_asyncio_executor():
-    """Sets up AsyncIO to run on a single thread.
+    """Sets up AsyncIO to run properly on each platform."""
 
-    This ensures that only one Pillar HTTP call is performed at the same time. Other
-    calls that could be performed in parallel are queued, and thus we can
-    reliably cancel them.
-    """
     import sys
 
-    executor = concurrent.futures.ThreadPoolExecutor()
-
     if sys.platform == 'win32':
+        asyncio.get_event_loop().close()
         # On Windows, the default event loop is SelectorEventLoop, which does
         # not support subprocesses. ProactorEventLoop should be used instead.
         # Source: https://docs.python.org/3/library/asyncio-subprocess.html
@@ -51,9 +46,15 @@ def setup_asyncio_executor():
         asyncio.set_event_loop(loop)
     else:
         loop = asyncio.get_event_loop()
+
+    executor = concurrent.futures.ThreadPoolExecutor(max_workers=10)
     loop.set_default_executor(executor)
     # loop.set_debug(True)
 
+    from . import pillar
+    # No more than this many Pillar calls should be made simultaneously
+    pillar.pillar_semaphore = asyncio.Semaphore(3, loop=loop)
+
 
 def kick_async_loop(*args) -> bool:
     """Performs a single iteration of the asyncio event loop.

blender_cloud/pillar.py

@@ -115,6 +115,12 @@ def with_existing_dir(filename: str, open_mode: str, encoding=None):
         yield file_object
 
 
+def _shorten(somestr: str, maxlen=40) -> str:
+    """Shortens strings for logging"""
+
+    return (somestr[:maxlen - 3] + '...') if len(somestr) > maxlen else somestr
+
+
 def save_as_json(pillar_resource, json_filename):
     with with_existing_dir(json_filename, 'w') as outfile:
         log.debug('Saving metadata to %r' % json_filename)
@@ -200,8 +206,11 @@ def pillar_api(pillar_endpoint: str = None, caching=True) -> pillarsdk.Api:
     return _pillar_api[caching]
 
 
-# No more than this many Pillar calls should be made simultaneously
-pillar_semaphore = asyncio.Semaphore(3)
+# This is an asyncio.Semaphore object, which is late-instantiated to be sure
+# the asyncio loop has been created properly. On Windows we create a new one,
+# which can cause this semaphore to still be linked against the old default
+# loop.
+pillar_semaphore = None
 
 
 async def pillar_call(pillar_func, *args, caching=True, **kwargs):
@@ -214,8 +223,21 @@ async def pillar_call(pillar_func, *args, caching=True, **kwargs):
     partial = functools.partial(pillar_func, *args, api=pillar_api(caching=caching), **kwargs)
     loop = asyncio.get_event_loop()
 
-    async with pillar_semaphore:
+    # Use explicit calls to acquire() and release() so that we have more control over
+    # how long we wait and how we handle timeouts.
+    try:
+        await asyncio.wait_for(pillar_semaphore.acquire(), timeout=10, loop=loop)
+    except asyncio.TimeoutError:
+        log.info('Waiting for semaphore to call %s', pillar_func.__name__)
+        try:
+            await asyncio.wait_for(pillar_semaphore.acquire(), timeout=50, loop=loop)
+        except asyncio.TimeoutError:
+            raise RuntimeError('Timeout waiting for Pillar Semaphore!')
+
+    try:
         return await loop.run_in_executor(None, partial)
+    finally:
+        pillar_semaphore.release()
 
 
 def sync_call(pillar_func, *args, caching=True, **kwargs):
@@ -441,9 +463,9 @@ async def download_to_file(url, filename, *,
         log.debug('Downloading was cancelled before doing the GET')
         raise asyncio.CancelledError('Downloading was cancelled')
 
-    log.debug('Performing GET %s', url)
+    log.debug('Performing GET %s', _shorten(url))
     response = await loop.run_in_executor(None, perform_get_request)
-    log.debug('Status %i from GET %s', response.status_code, url)
+    log.debug('Status %i from GET %s', response.status_code, _shorten(url))
     response.raise_for_status()
 
     if response.status_code == 304:
@@ -457,9 +479,9 @@ async def download_to_file(url, filename, *,
         log.debug('Downloading was cancelled before downloading the GET response')
         raise asyncio.CancelledError('Downloading was cancelled')
 
-    log.debug('Downloading response of GET %s', url)
+    log.debug('Downloading response of GET %s', _shorten(url))
     await loop.run_in_executor(None, download_loop)
-    log.debug('Done downloading response of GET %s', url)
+    log.debug('Done downloading response of GET %s', _shorten(url))
 
     # We're done downloading, now we have something cached we can use.
     log.debug('Saving header cache to %s', header_store)
@@ -534,7 +556,8 @@ async def fetch_texture_thumbs(parent_node_uuid: str, desired_size: str,
              for texture_node in texture_nodes)
 
     # raises any exception from failed handle_texture_node() calls.
-    await asyncio.gather(*coros)
+    loop = asyncio.get_event_loop()
+    await asyncio.gather(*coros, loop=loop)
 
     log.info('fetch_texture_thumbs: Done downloading texture thumbnails')
 
@@ -747,7 +770,8 @@ async def download_texture(texture_node,
                                     future=future)
         downloaders.append(dlr)
 
-    return await asyncio.gather(*downloaders, return_exceptions=True)
+    loop = asyncio.get_event_loop()
+    return await asyncio.gather(*downloaders, return_exceptions=True, loop=loop)
 
 
 async def upload_file(project_id: str, file_path: pathlib.Path, *,
@@ -773,9 +797,9 @@ async def upload_file(project_id: str, file_path: pathlib.Path, *,
         log.debug('Uploading was cancelled before doing the POST')
         raise asyncio.CancelledError('Uploading was cancelled')
 
-    log.debug('Performing POST %s', url)
+    log.debug('Performing POST %s', _shorten(url))
     response = await loop.run_in_executor(None, upload)
-    log.debug('Status %i from POST %s', response.status_code, url)
+    log.debug('Status %i from POST %s', response.status_code, _shorten(url))
     response.raise_for_status()
 
     resp = response.json()

blender_cloud/texture_browser.py

@@ -457,7 +457,7 @@ class BlenderCloudBrowser(pillar.PillarOperatorMixin,
 
         return menu_item
 
-    def update_menu_item(self, node, *args) -> MenuItem:
+    def update_menu_item(self, node, *args):
         node_uuid = node['_id']
 
         # Just make this thread-safe to be on the safe side.
@@ -538,6 +538,7 @@ class BlenderCloudBrowser(pillar.PillarOperatorMixin,
             self.add_menu_item(node, None, 'SPINNER', texture_node['name'])
 
         def thumbnail_loaded(node, file_desc, thumb_path):
+            self.log.debug('Node %s thumbnail loaded', node['_id'])
             self.update_menu_item(node, file_desc, thumb_path)
 
         await pillar.fetch_texture_thumbs(node_uuid, 's', directory,

setup.py

@@ -227,7 +227,7 @@ setup(
               'wheels': BuildWheels},
     name='blender_cloud',
     description='The Blender Cloud addon allows browsing the Blender Cloud from Blender.',
-    version='1.7.0',
+    version='1.7.1',
     author='Sybren A. Stüvel',
     author_email='sybren@stuvel.eu',
     packages=find_packages('.'),