addressing #88

CHANGES.md

@@ -1,5 +1,7 @@
 ## Changes in 0.9.6 (in development)
 
+* Implemented performance optimizations for use of datasets 
+  in xcube server. (#88)
 * The open parameter `variable_names` in the `sentinelhub` data store  
   is now optional. 
 * Fixed some import statements to be compatible with Python 3.10.

test/test_cube.py

@@ -19,6 +19,7 @@
 # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 # DEALINGS IN THE SOFTWARE.
 
+import collections.abc
 import unittest
 
 import numpy as np
@@ -106,17 +107,28 @@ class CubeTest(unittest.TestCase):
     def test_open_cube(self):
         cube = open_cube(cube_config=cube_config)
         self.assertIsInstance(cube, xr.Dataset)
+        self.assert_has_zarr_store(cube)
 
     def test_time_max_none(self):
         cube = open_cube(cube_config=cube_config_t1_none)
         self.assertIsInstance(cube, xr.Dataset)
-        self.assertEqual(np.datetime64('today', 'D'), np.datetime64(cube.time.values[-1], 'D'))  # self.assertEqual()
+        self.assertEqual(np.datetime64('today', 'D'),
+                         np.datetime64(cube.time.values[-1], 'D'))
+        self.assert_has_zarr_store(cube)
 
     def test_time_none(self):
         cube = open_cube(cube_config=cube_config_t_none)
         self.assertIsInstance(cube, xr.Dataset)
-        self.assertEqual(np.datetime64('2021-02-16'), np.datetime64(cube.time.values[-1], 'D'))  # self.assertEqual()
-        self.assertEqual(np.datetime64('2015-06-27'), np.datetime64(cube.time.values[0], 'D'))  # self.assertEqual()
+        self.assertEqual(np.datetime64('2021-02-16'),
+                         np.datetime64(cube.time.values[-1], 'D'))
+        self.assertEqual(np.datetime64('2015-06-27'),
+                         np.datetime64(cube.time.values[0], 'D'))
+        self.assert_has_zarr_store(cube)
+
+    def assert_has_zarr_store(self, cube):
+        if hasattr(cube, 'zarr_store'):
+            self.assertIsInstance(cube.zarr_store.get(),
+                                  collections.abc.Mapping)
 
 
 @unittest.skipUnless(HAS_SH_CREDENTIALS, REQUIRE_SH_CREDENTIALS)

xcube_sh/cube.py

@@ -66,4 +66,9 @@ def open_cube(cube_config: CubeConfig,
                                        trace_store_calls=trace_store_calls)
     if max_cache_size:
         cube_store = zarr.LRUStoreCache(cube_store, max_cache_size)
-    return xr.open_zarr(cube_store)
+
+    cube = xr.open_zarr(cube_store)
+    if hasattr(cube, 'zarr_store'):
+        cube.zarr_store.set(cube_store)
+
+    return cube

xcube_sh/store.py

@@ -207,7 +207,12 @@ def open_data(self, data_id: str, **open_params) -> xr.Dataset:
         if max_cache_size:
             chunk_store = zarr.LRUStoreCache(chunk_store,
                                              max_size=max_cache_size)
-        return xr.open_zarr(chunk_store, **open_params)
+        cube = xr.open_zarr(chunk_store, **open_params)
+
+        if hasattr(cube, 'zarr_store'):
+            cube.zarr_store.set(chunk_store)
+
+        return cube
 
     ##########################################################################
     # Implementation helpers