samples: Add multi_range_downloader samples

google/cloud/storage/_experimental/asyncio/async_multi_range_downloader.py

@@ -71,23 +71,16 @@ class AsyncMultiRangeDownloader:
             client, bucket_name="chandrasiri-rs", object_name="test_open9"
         )
         my_buff1 = open('my_fav_file.txt', 'wb')
-        my_buff1 = open('my_fav_file.txt', 'wb')
         my_buff2 = BytesIO()
         my_buff3 = BytesIO()
         my_buff4 = any_object_which_provides_BytesIO_like_interface()
-        results_arr, error_obj = await mrd.download_ranges(
-        my_buff4 = any_object_which_provides_BytesIO_like_interface()
         results_arr, error_obj = await mrd.download_ranges(
             [
-                # (start_byte, bytes_to_read, writeable_buffer)
                 # (start_byte, bytes_to_read, writeable_buffer)
                 (0, 100, my_buff1),
                 (100, 20, my_buff2),
                 (200, 123, my_buff3),
                 (300, 789, my_buff4),
-                (100, 20, my_buff2),
-                (200, 123, my_buff3),
-                (300, 789, my_buff4),
             ]
         )
         if error_obj:
@@ -101,17 +94,6 @@ class AsyncMultiRangeDownloader:
         for result in results_arr:
             print("downloaded bytes", result)
 
-        if error_obj:
-            print("Error occurred: ")
-            print(error_obj)
-            print(
-                "please issue call to `download_ranges` with updated"
-                "`read_ranges` based on diff of (bytes_requested - bytes_written)"
-            )
-
-        for result in results_arr:
-            print("downloaded bytes", result)
-
 
     """
 

samples/snippets/experimental/storage_download_ranges_async.py

@@ -0,0 +1,53 @@
+from google.cloud.storage._experimental.asyncio.async_multi_range_downloader import (
+    AsyncMultiRangeDownloader,
+)
+from google.cloud.storage._experimental.asyncio.async_grpc_client import (
+    AsyncGrpcClient,
+)
+from io import BytesIO
+import asyncio
+import argparse
+
+
+async def test_mrd(bucket_name, object_name, generation_number=None):
+    client = AsyncGrpcClient()._grpc_client
+
+    mrd = AsyncMultiRangeDownloader(client, bucket_name, object_name, generation_number)
+    await mrd.open()
+    # create buffers.
+    # Make sure buffer desitnation has enough space to accomodate bytes requetsed.
+    # Buffers could be in-memory or on disk
+    my_buff1 = open(f"sample_file_to_write_contents.txt", "wb")
+    my_buff2 = BytesIO()
+    my_buff3 = BytesIO()
+    my_buff4 = BytesIO()
+    results_arr, error_obj = await mrd.download_ranges(
+        [
+            (0, 100, my_buff1),
+            (100, 20, my_buff2),
+            (200, 123, my_buff3),
+            (300, 789, my_buff4),
+        ]
+    )
+    if error_obj:
+        print("Error occurred: ")
+        print(error_obj)
+        print(
+            "please issue call to `download_ranges` with updated"
+            "`read_ranges` based on diff of (bytes_requested - bytes_written)"
+        )
+
+    for result in results_arr:
+        print("downloaded bytes", result)
+
+    # close MRD
+    await mrd.close()
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--bucket_name", type=str, required=True)
+    parser.add_argument("--object_name", type=str, required=True)
+    parser.add_argument("--generation_number", type=int, default=None)
+    args = parser.parse_args()
+    asyncio.run(test_mrd(args.bucket_name, args.object_name, args.generation_number))