fix: encode interaction media bytes

google/genai/_interactions/_files.py

@@ -39,7 +39,9 @@
 
 
 def is_base64_file_input(obj: object) -> TypeGuard[Base64FileInput]:
-    return isinstance(obj, io.IOBase) or isinstance(obj, os.PathLike)
+    return isinstance(obj, bytes) or isinstance(obj, io.IOBase) or isinstance(
+        obj, os.PathLike
+    )
 
 
 def is_file_content(obj: object) -> TypeGuard[FileContent]:

google/genai/_interactions/_types.py

@@ -71,10 +71,10 @@
 ProxiesDict = Dict["str | URL", Union[None, str, URL, Proxy]]
 ProxiesTypes = Union[str, Proxy, ProxiesDict]
 if TYPE_CHECKING:
-    Base64FileInput = Union[IO[bytes], PathLike[str]]
+    Base64FileInput = Union[IO[bytes], bytes, PathLike[str]]
     FileContent = Union[IO[bytes], bytes, PathLike[str]]
 else:
-    Base64FileInput = Union[IO[bytes], PathLike]
+    Base64FileInput = Union[IO[bytes], bytes, PathLike]
     FileContent = Union[IO[bytes], bytes, PathLike]  # PathLike is not subscriptable in Python 3.8.
 
 

google/genai/_interactions/_utils/_transform.py

@@ -259,7 +259,9 @@ def _format_data(data: object, format_: PropertyFormat, format_template: str | N
     if format_ == "base64" and is_base64_file_input(data):
         binary: str | bytes | None = None
 
-        if isinstance(data, pathlib.Path):
+        if isinstance(data, bytes):
+            binary = data
+        elif isinstance(data, pathlib.Path):
             binary = data.read_bytes()
         elif isinstance(data, io.IOBase):
             binary = data.read()
@@ -425,7 +427,9 @@ async def _async_format_data(data: object, format_: PropertyFormat, format_templ
     if format_ == "base64" and is_base64_file_input(data):
         binary: str | bytes | None = None
 
-        if isinstance(data, pathlib.Path):
+        if isinstance(data, bytes):
+            binary = data
+        elif isinstance(data, pathlib.Path):
             binary = await anyio.Path(data).read_bytes()
         elif isinstance(data, io.IOBase):
             binary = data.read()

google/genai/tests/interactions/test_base64_inputs.py

@@ -0,0 +1,81 @@
+# Copyright 2026 Google LLC
+#
+# 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.
+
+import base64
+
+import pytest
+
+from ..._interactions._utils import async_maybe_transform
+from ..._interactions._utils import maybe_transform
+from ..._interactions._utils._json import openapi_dumps
+from ..._interactions.types import interaction_create_params
+
+
+@pytest.mark.parametrize(
+    'content_type,mime_type',
+    [
+        ('image', 'image/png'),
+        ('audio', 'audio/wav'),
+        ('video', 'video/mp4'),
+        ('document', 'application/pdf'),
+    ],
+)
+def test_media_input_bytes_are_base64_encoded(content_type, mime_type):
+  body = maybe_transform(
+      {
+          'input': {
+              'type': content_type,
+              'data': b'media-bytes',
+              'mime_type': mime_type,
+          },
+          'model': 'gemini-2.5-flash',
+      },
+      interaction_create_params.CreateModelInteractionParamsNonStreaming,
+  )
+
+  assert body['input']['data'] == base64.b64encode(b'media-bytes').decode(
+      'ascii'
+  )
+  assert openapi_dumps(body)
+
+
+@pytest.mark.parametrize(
+    'content_type,mime_type',
+    [
+        ('image', 'image/png'),
+        ('audio', 'audio/wav'),
+        ('video', 'video/mp4'),
+        ('document', 'application/pdf'),
+    ],
+)
+@pytest.mark.asyncio
+async def test_media_input_bytes_are_base64_encoded_async(
+    content_type, mime_type
+):
+  body = await async_maybe_transform(
+      {
+          'input': {
+              'type': content_type,
+              'data': b'media-bytes',
+              'mime_type': mime_type,
+          },
+          'model': 'gemini-2.5-flash',
+      },
+      interaction_create_params.CreateModelInteractionParamsNonStreaming,
+  )
+
+  assert body['input']['data'] == base64.b64encode(b'media-bytes').decode(
+      'ascii'
+  )
+  assert openapi_dumps(body)