Pass engine to xr.open_mfdataset in OpenDapSource

When OpenDapSource._open_dataset is called when urlpath is a list of
OPeNDAP URLs, no engine is specified in the call to xr.open_mfdataset
even if engine is set in the class. This prevents clients from using a
specified engine and reverts to xarray's default engine selection.

This commit changes the call to xr.open_mfdataset to include the engine
argument as the self.engine value.

Author: lukecampbell

intake_xarray/opendap.py

@@ -92,7 +92,7 @@ def _open_dataset(self):
         import xarray as xr
 
         if isinstance(self.urlpath, list):
-            self._ds = xr.open_mfdataset(self.urlpath, chunks=self.chunks, **self._kwargs)
+            self._ds = xr.open_mfdataset(self.urlpath, chunks=self.chunks, engine=self.engine, **self._kwargs)
         else:
             store = self._get_store()
-            self._ds = xr.open_dataset(store, chunks=self.chunks, **self._kwargs)
+            self._ds = xr.open_dataset(store, chunks=self.chunks, **self._kwargs)