Merge pull request #722 from planetlabs/downloading_asset_example-719

Downloading multiple assets in parallel example

Author: kevinlacaille

examples/download_multiple_assets.py

@@ -0,0 +1,67 @@
+# Copyright 2022 Planet Labs PBC.
+#
+# Licensed 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.
+"""Example of downloading multiple assets in parallel
+
+This is an example of getting two assets, activating them, waiting for them to
+become active, downloading them, then validating the checksums of downloaded
+files.
+
+[Planet Explorer](https://www.planet.com/explorer/) was used to define
+the AOIs and get the image ids.
+"""
+import asyncio
+
+from planet import Session, DataClient
+
+river_item_id = '20221003_002705_38_2461'
+river_item_type = 'PSScene'
+river_asset_type = 'ortho_analytic_4b'
+
+wildfire_item_id = '20221019_183717_11_2475'
+wildfire_item_type = 'PSScene'
+wildfire_asset_type = 'basic_analytic_4b'
+
+
+async def download_and_validate(item_id, item_type_id, asset_type_id):
+    async with Session() as sess:
+        # Data client object
+        cl = DataClient(sess)
+
+        # Get asset description
+        asset = await cl.get_asset(item_type_id, item_id, asset_type_id)
+
+        # Activate asset
+        await cl.activate_asset(asset)
+
+        # Wait for asset to become active
+        asset = await cl.wait_asset(asset, callback=print)
+
+        # Download asset
+        path = await cl.download_asset(asset)
+
+        # Validate download file
+        cl.validate_checksum(asset, path)
+
+
+async def main():
+    await asyncio.gather(
+        download_and_validate(river_item_id, river_item_type,
+                              river_asset_type),
+        download_and_validate(wildfire_item_id,
+                              wildfire_item_type,
+                              wildfire_asset_type))
+
+
+if __name__ == '__main__':
+    asyncio.run(main())