merge_cubes: merge temporal extents

#852
#861

openeogeotrellis/geopysparkcubemetadata.py

@@ -2,7 +2,7 @@
 from typing import List, Union
 
 import dateutil.parser
-from openeo.metadata import CollectionMetadata, Dimension
+from openeo.metadata import CollectionMetadata, Dimension, TemporalDimension
 from openeogeotrellis.utils import reproject_cellsize
 
 _log = logging.getLogger(__name__)
@@ -73,7 +73,8 @@ def filter_temporal(self, start, end) -> 'GeopysparkCubeMetadata':
 
         this_start, this_end = self._temporal_extent
 
-        if this_start > end or this_end < start:  # no overlap
+        if this_start > end or this_end < start:  # compared lexicographically
+            # no overlap
             raise ValueError(start, end)
 
         return self._clone_and_update(temporal_extent=(max(this_start, start), min(this_end, end)))
@@ -82,6 +83,17 @@ def filter_temporal(self, start, end) -> 'GeopysparkCubeMetadata':
     def temporal_extent(self) -> tuple:
         return self._temporal_extent
 
+    def with_temporal_extent(self, temporal_extent: tuple):
+        assert self.has_temporal_dimension()
+
+        return self._clone_and_update(
+            dimensions=[
+                TemporalDimension(d.name, temporal_extent) if isinstance(d, TemporalDimension) else d
+                for d in self._dimensions
+            ],
+            temporal_extent=temporal_extent,
+        )
+
     @property
     def opensearch_link_titles(self) -> List[str]:
         """Get opensearch_link_titles from band dimension"""

openeogeotrellis/geopysparkdatacube.py

@@ -945,7 +945,7 @@ def merge_cubes(self, other: 'GeopysparkDataCube', overlaps_resolver:str=None):
                     + f" Left names: {leftBandNames}, right names: {rightBandNames}.",
                 )
 
-        # TODO properly combine bbox and temporal extents in metadata? Yes! Then pass to _apply_to_levels_geotrellis_rdd
+        # TODO properly combine bbox in metadata?
         pr = pysc._jvm.org.openeo.geotrellis.OpenEOProcesses()
         if self._is_spatial() and other._is_spatial():
             def merge(rdd,other,level):
@@ -1003,6 +1003,14 @@ def merge(rdd,other,level):
                 if iband.name not in merged_data.metadata.band_names:
                     merged_data.metadata = merged_data.metadata.append_band(iband)
 
+        if self.metadata.has_temporal_dimension() and other.metadata.has_temporal_dimension():
+            self_lower, self_upper = self.metadata.temporal_dimension.extent
+            other_lower, other_upper = other.metadata.temporal_dimension.extent
+
+            merged_data.metadata = merged_data.metadata.with_temporal_extent(
+                (min([self_lower, other_lower]), max([self_upper, other_upper]))  # compared lexicographically
+            )
+
         return merged_data
 
     # TODO legacy alias to be removed