testing

python_modules/dagster/dagster_tests/core_tests/execution_tests/test_context.py

@@ -4,18 +4,23 @@
 import pytest
 from dagster import (
     AssetCheckResult,
+    AssetDep,
     AssetExecutionContext,
+    AssetKey,
     AssetOut,
     DagsterInstance,
+    DailyPartitionsDefinition,
     Definitions,
     GraphDefinition,
     MaterializeResult,
     OpExecutionContext,
     Output,
+    TimeWindowPartitionMapping,
     asset,
     asset_check,
     graph_asset,
     graph_multi_asset,
+    instance_for_test,
     job,
     materialize,
     multi_asset,
@@ -437,7 +442,7 @@ def upstream(context: AssetExecutionContext):
 
     @asset
     def downstream(context: AssetExecutionContext, upstream):
-        mat = context.latest_materialization_for_upstream_asset("upstream")
+        mat = context.fetch_latest_materialization_for_upstream_asset("upstream")
         assert mat is not None
         assert mat.metadata["foo"].value == "bar"
 
@@ -452,8 +457,80 @@ def upstream():
 
     @asset
     def downstream(context: AssetExecutionContext, upstream):
-        mat = context.latest_materialization_for_upstream_asset("upstream")
+        mat = context.fetch_latest_materialization_for_upstream_asset("upstream")
         assert mat is not None
         assert mat.metadata["foo"].value == "bar"
 
     materialize([upstream, downstream])
+
+
+def test_upstream_metadata_with_partitions():
+    partitions_def = DailyPartitionsDefinition(start_date="2024-01-01")
+    first_materialization_partition_key = "2024-01-01"
+    second_materialization_partition_key = "2024-01-02"
+
+    @asset(partitions_def=partitions_def)
+    def upstream(context):
+        return MaterializeResult(metadata={"partition_key": context.partition_key})
+
+    @asset(partitions_def=partitions_def, deps=[upstream])
+    def downstream(context: AssetExecutionContext):
+        mat = context.fetch_latest_materialization_for_upstream_asset("upstream")
+        assert mat is not None
+        assert mat.metadata["partition_key"].value == context.partition_key
+
+        # upstream_asset_materialization_events has the latest AssetMaterialization and is not scoped to
+        # a specific partition
+        latest_mat = context._step_execution_context.upstream_asset_materialization_events.get(  # noqa: SLF001
+            AssetKey.from_coercible("upstream")
+        )
+        assert latest_mat is not None
+        assert latest_mat.metadata["partition_key"].value != context.partition_key
+        assert latest_mat.metadata["partition_key"].value == second_materialization_partition_key
+
+        with instance_for_test() as instance:
+            materialize(
+                [upstream], partition_key=first_materialization_partition_key, instance=instance
+            )
+
+            # the metadata from this materialization will be what's in upstream_asset_materialization_events
+            materialize(
+                [upstream], partition_key=second_materialization_partition_key, instance=instance
+            )
+
+            # asserts that fetch_latest_materialization_for_upstream_asset gets the AssetMaterialization
+            # scoped to the correct partition, not just the latest AssetMaterialization
+            materialize(
+                [downstream], partition_key=first_materialization_partition_key, instance=instance
+            )
+
+
+def test_upstream_metadata_with_partition_mapping():
+    partitions_def = DailyPartitionsDefinition(start_date="2024-01-01")
+
+    @asset(partitions_def=partitions_def)
+    def upstream(context):
+        return MaterializeResult(metadata={"partition_key": context.partition_key})
+
+    @asset(
+        partitions_def=partitions_def,
+        deps=[
+            AssetDep(asset=upstream, partition_mapping=TimeWindowPartitionMapping(start_offset=-2))
+        ],
+    )
+    def downstream(context: AssetExecutionContext):
+        with pytest.raises(DagsterInvariantViolationError):
+            context.fetch_latest_materialization_for_upstream_asset("upstream")
+
+        mat = context.fetch_latest_materialization_for_upstream_asset(
+            "upstream", partition_key="2024-01-01"
+        )
+        assert mat is not None
+        assert mat.metadata["partition_key"].value == "2024-01-01"
+
+        with instance_for_test() as instance:
+            materialize([upstream], partition_key="2024-01-01", instance=instance)
+            materialize([upstream], partition_key="2024-01-02", instance=instance)
+            materialize([upstream], partition_key="2024-01-03", instance=instance)
+
+            materialize([downstream], partition_key="2024-01-03", instance=instance)