Remove imghdr (#282)

Give a 21 print line salute to imghdr which is slated for removal from
the standard library

---------

Co-authored-by: Auto-format Bot <autoformatbot@groundlight.ai>

Author: brandon-wada

src/groundlight/images.py

@@ -1,6 +1,6 @@
 # pylint: disable=deprecated-module
-import imghdr
 from io import BufferedReader, BytesIO, IOBase
+from pathlib import Path
 from typing import Union
 
 from groundlight.optional_imports import Image, np
@@ -37,10 +37,11 @@ def bytestream_from_filename(image_filename: str, jpeg_quality: int = DEFAULT_JP
     Only supports JPEG and PNG files for now.
     For PNG files, we convert to RGB format used in JPEGs.
     """
-    if imghdr.what(image_filename) == "jpeg":
+    image_path = Path(image_filename)
+    if image_path.suffix.lower() in (".jpeg", ".jpg"):
         buffer = buffer_from_jpeg_file(image_filename)
         return ByteStreamWrapper(data=buffer)
-    if imghdr.what(image_filename) == "png":
+    if image_path.suffix.lower() == ".png":
         pil_img = Image.open(image_filename)
         # This chops off the alpha channel which can cause unexpected behavior, but handles minimal transparency well
         pil_img = pil_img.convert("RGB")
@@ -53,7 +54,7 @@ def buffer_from_jpeg_file(image_filename: str) -> BufferedReader:
 
     For now, we only support JPEG files, and raise an ValueError otherwise.
     """
-    if imghdr.what(image_filename) == "jpeg":
+    if Path(image_filename).suffix.lower() in (".jpeg", ".jpg"):
         # Note this will get fooled by truncated binaries since it only reads the header.
         # That's okay - the server will catch it.
         return open(image_filename, "rb")

test/integration/test_groundlight.py

@@ -470,11 +470,16 @@ def test_submit_image_query_bad_filename(gl: Groundlight, detector: Detector):
 
 
 def test_submit_image_query_bad_jpeg_file(gl: Groundlight, detector: Detector):
-    with pytest.raises(ValueError) as exc_info:
+    with pytest.raises(ApiException) as exc_info:
         _image_query = gl.submit_image_query(
             detector=detector.id, image="test/assets/blankfile.jpeg", human_review="NEVER"
         )
-    assert "jpeg" in str(exc_info).lower()
+    assert "uploaded image is empty or corrupted" in exc_info.value.body.lower()
+    with pytest.raises(ValueError) as exc_info:
+        _image_query = gl.submit_image_query(
+            detector=detector.id, image="test/assets/blankfile.jpeeeg", human_review="NEVER"
+        )
+    assert "we only support jpeg and png" in str(exc_info).lower()
 
 
 @pytest.mark.skipif(MISSING_PIL, reason="Needs pillow")  # type: ignore