use globals instead of threading.local (fixes #281) (#282)

* use globals instead of threading.local (fixes #281)

* fix broken tesT

* satisfy mypy

terracotta/drivers/geotiff_raster_store.py

@@ -23,8 +23,7 @@
 
 logger = logging.getLogger(__name__)
 
-context = threading.local()
-context.executor = None
+_executor = None
 
 
 def create_executor() -> Executor:
@@ -50,16 +49,18 @@ def create_executor() -> Executor:
 
 
 def submit_to_executor(task: Callable[..., Any]) -> Future:
-    if context.executor is None:
-        context.executor = create_executor()
+    global _executor
+
+    if _executor is None:
+        _executor = create_executor()
 
     try:
-        future = context.executor.submit(task)
+        future = _executor.submit(task)
     except BrokenProcessPool:
         # re-create executor and try again
         logger.warn('Re-creating broken process pool')
-        context.executor = create_executor()
-        future = context.executor.submit(task)
+        _executor = create_executor()
+        future = _executor.submit(task)
 
     return future
 

terracotta/drivers/relational_meta_store.py

@@ -171,7 +171,7 @@ def version_tuple(version_string: str) -> Sequence[str]:
                 )
             self.db_version_verified = True
 
-    @property  # type: ignore
+    @property
     @requires_connection
     @convert_exceptions(_ERROR_ON_CONNECT)
     def db_version(self) -> str:

tests/drivers/test_raster_drivers.py

@@ -504,31 +504,32 @@ def test_nodata_consistency(driver_path, provider, big_raster_file_mask, big_ras
 
 
 @pytest.mark.parametrize('provider', DRIVERS)
-def test_broken_process_pool(driver_path, provider, raster_file):
+def test_broken_process_pool(monkeypatch, driver_path, provider, raster_file):
     import concurrent.futures
+    import terracotta.drivers.geotiff_raster_store
     from terracotta import drivers
-    from terracotta.drivers.geotiff_raster_store import context
 
     class BrokenPool:
         def submit(self, *args, **kwargs):
             raise concurrent.futures.process.BrokenProcessPool('monkeypatched')
 
-    context.executor = BrokenPool()
+    with monkeypatch.context() as m:
+        m.setattr(terracotta.drivers.geotiff_raster_store, '_executor', BrokenPool())
 
-    db = drivers.get_driver(driver_path, provider=provider)
-    keys = ('some', 'keynames')
+        db = drivers.get_driver(driver_path, provider=provider)
+        keys = ('some', 'keynames')
 
-    db.create(keys)
-    db.insert(['some', 'value'], str(raster_file))
-    db.insert(['some', 'other_value'], str(raster_file))
+        db.create(keys)
+        db.insert(['some', 'value'], str(raster_file))
+        db.insert(['some', 'other_value'], str(raster_file))
 
-    data1 = db.get_raster_tile(['some', 'value'], tile_size=(256, 256))
-    assert data1.shape == (256, 256)
+        data1 = db.get_raster_tile(['some', 'value'], tile_size=(256, 256))
+        assert data1.shape == (256, 256)
 
-    data2 = db.get_raster_tile(['some', 'other_value'], tile_size=(256, 256))
-    assert data2.shape == (256, 256)
+        data2 = db.get_raster_tile(['some', 'other_value'], tile_size=(256, 256))
+        assert data2.shape == (256, 256)
 
-    np.testing.assert_array_equal(data1, data2)
+        np.testing.assert_array_equal(data1, data2)
 
 
 def test_no_multiprocessing():