feat: import/export assets commands (#19217)

* feat: import/export assets commands

* Add overwrite test

* Fix tests

tests/unit_tests/commands/export_test.py

@@ -0,0 +1,94 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# pylint: disable=invalid-name, unused-argument, import-outside-toplevel
+
+from freezegun import freeze_time
+from pytest_mock import MockFixture
+
+
+def test_export_assets_command(mocker: MockFixture, app_context: None) -> None:
+    """
+    Test that all assets are exported correctly.
+    """
+    from superset.commands.export.assets import ExportAssetsCommand
+
+    ExportDatabasesCommand = mocker.patch(
+        "superset.commands.export.assets.ExportDatabasesCommand"
+    )
+    ExportDatabasesCommand.return_value.run.return_value = [
+        (
+            "metadata.yaml",
+            "version: 1.0.0\ntype: Database\ntimestamp: '2022-01-01T00:00:00+00:00'\n",
+        ),
+        ("databases/example.yaml", "<DATABASE CONTENTS>"),
+    ]
+    ExportDatasetsCommand = mocker.patch(
+        "superset.commands.export.assets.ExportDatasetsCommand"
+    )
+    ExportDatasetsCommand.return_value.run.return_value = [
+        (
+            "metadata.yaml",
+            "version: 1.0.0\ntype: Dataset\ntimestamp: '2022-01-01T00:00:00+00:00'\n",
+        ),
+        ("datasets/example/dataset.yaml", "<DATASET CONTENTS>"),
+    ]
+    ExportChartsCommand = mocker.patch(
+        "superset.commands.export.assets.ExportChartsCommand"
+    )
+    ExportChartsCommand.return_value.run.return_value = [
+        (
+            "metadata.yaml",
+            "version: 1.0.0\ntype: Slice\ntimestamp: '2022-01-01T00:00:00+00:00'\n",
+        ),
+        ("charts/pie.yaml", "<CHART CONTENTS>"),
+    ]
+    ExportDashboardsCommand = mocker.patch(
+        "superset.commands.export.assets.ExportDashboardsCommand"
+    )
+    ExportDashboardsCommand.return_value.run.return_value = [
+        (
+            "metadata.yaml",
+            "version: 1.0.0\ntype: Dashboard\ntimestamp: '2022-01-01T00:00:00+00:00'\n",
+        ),
+        ("dashboards/sales.yaml", "<DASHBOARD CONTENTS>"),
+    ]
+    ExportSavedQueriesCommand = mocker.patch(
+        "superset.commands.export.assets.ExportSavedQueriesCommand"
+    )
+    ExportSavedQueriesCommand.return_value.run.return_value = [
+        (
+            "metadata.yaml",
+            "version: 1.0.0\ntype: SavedQuery\ntimestamp: '2022-01-01T00:00:00+00:00'\n",
+        ),
+        ("queries/example/metric.yaml", "<SAVED QUERY CONTENTS>"),
+    ]
+
+    with freeze_time("2022-01-01T00:00:00Z"):
+        command = ExportAssetsCommand()
+        output = list(command.run())
+
+    assert output == [
+        (
+            "metadata.yaml",
+            "version: 1.0.0\ntype: assets\ntimestamp: '2022-01-01T00:00:00+00:00'\n",
+        ),
+        ("databases/example.yaml", "<DATABASE CONTENTS>"),
+        ("datasets/example/dataset.yaml", "<DATASET CONTENTS>"),
+        ("charts/pie.yaml", "<CHART CONTENTS>"),
+        ("dashboards/sales.yaml", "<DASHBOARD CONTENTS>"),
+        ("queries/example/metric.yaml", "<SAVED QUERY CONTENTS>"),
+    ]