add test

aiocogeo/tag.py

@@ -4,13 +4,13 @@
 
 from typing import Any, Optional, Tuple, Union
 
-from .config import HEADER_CHUNK_SIZE, LOG_LEVEL
+from . import config
 from .constants import GEO_KEYS, TIFF_TAGS
 from .filesystems import Filesystem
 
 
 logger = logging.getLogger(__name__)
-logger.setLevel(LOG_LEVEL)
+logger.setLevel(config.LOG_LEVEL)
 
 
 @dataclass
@@ -89,7 +89,7 @@ async def read(cls, reader: Filesystem) -> Optional["Tag"]:
             if value_offset + length > current_size:
 
                 # we coerce the chunk size to be at least the size of the tag
-                chunk_size = max(value_offset + length - current_size, HEADER_CHUNK_SIZE)
+                chunk_size = max(value_offset + length - current_size, config.HEADER_CHUNK_SIZE)
                 reader.data += await reader.range_request(len(reader.data), chunk_size, is_header=True)
 
             # read the tag value

tests/test_metadata.py

@@ -3,6 +3,7 @@
 import pytest
 import rasterio
 
+from aiocogeo import config
 from aiocogeo.ifd import IFD
 from aiocogeo.tag import BaseTag
 from aiocogeo.errors import InvalidTiffError
@@ -168,4 +169,20 @@ async def test_cog_not_a_tiff(create_cog_reader):
 async def test_file_not_found(create_cog_reader, infile):
     with pytest.raises(FileNotFoundError):
         async with create_cog_reader(infile) as cog:
-            ...
+            ...
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize(
+    "chunk_size,request_count,header_size", [
+        [16384, 2, 32770],
+        [4096, 4, 28769],
+        [100, 14, 26776]
+    ]
+)
+async def test_chunk_size(chunk_size, request_count, header_size, monkeypatch, create_cog_reader):
+    monkeypatch.setattr(config, "HEADER_CHUNK_SIZE", chunk_size)
+    async with create_cog_reader("https://async-cog-reader-test-data.s3.amazonaws.com/webp_cog.tif") as cog:
+        requests = cog.requests
+        assert requests['count'] == request_count
+        assert requests['header_size'] == header_size