Add chat image upload support

tests/test_chat_client.py

@@ -162,6 +162,120 @@ class TestChatClientCreateChatCompletion:
         mock_send.assert_called_once()
 
 
+class TestChatClientFileUpload:
+    """Test suite for ChatClient chat file upload helpers."""
+
+    def test_presign_chat_file_post_url_uses_local_path(self, api_key):
+        client = ChatClient(api_key)
+
+        mock_response = Mock(spec=httpx.Response)
+        mock_response.status_code = 200
+        mock_response.json = Mock(return_value={
+            "code": 200,
+            "message": "",
+            "data": {"url": "https://s3.example/upload", "fields": {"key": "chat/file.png"}},
+        })
+
+        with patch.object(client, "_send_request", return_value=mock_response) as mock_send:
+            result = client.presign_chat_file_post_url(
+                appId="app-123",
+                chatId="chat-123",
+                filename="file.png",
+                fileSelectConfig={"canSelectImg": True},
+            )
+
+        assert result["fields"]["key"] == "chat/file.png"
+        assert mock_send.call_args[0][1] == "/api/core/chat/presignChatFilePostUrl"
+        assert mock_send.call_args[1]["json"]["fileSelectConfig"] == {"canSelectImg": True}
+
+    def test_presign_chat_file_get_url_unwraps_string(self, api_key):
+        client = ChatClient(api_key)
+
+        mock_response = Mock(spec=httpx.Response)
+        mock_response.status_code = 200
+        mock_response.json = Mock(return_value={
+            "code": 200,
+            "message": "",
+            "data": "https://s3.example/preview.png",
+        })
+
+        with patch.object(client, "_send_request", return_value=mock_response) as mock_send:
+            result = client.presign_chat_file_get_url(appId="app-123", key="chat/file.png")
+
+        assert result == "https://s3.example/preview.png"
+        assert mock_send.call_args[0][1] == "/api/core/chat/presignChatFileGetUrl"
+
+    def test_upload_to_presigned_url_with_post_fields(self, api_key, tmp_path):
+        client = ChatClient(api_key)
+        file_path = tmp_path / "file.png"
+        file_path.write_bytes(b"png")
+
+        mock_response = Mock(spec=httpx.Response)
+        mock_response.raise_for_status = Mock()
+
+        with patch("fastgpt_client.client.httpx.post", return_value=mock_response) as mock_post:
+            response = client.upload_to_presigned_url(
+                upload_url="https://s3.example/upload",
+                file_path=file_path,
+                fields={"key": "chat/file.png", "policy": "abc"},
+            )
+
+        assert response is mock_response
+        mock_post.assert_called_once()
+        assert mock_post.call_args[1]["data"] == {"key": "chat/file.png", "policy": "abc"}
+        assert "file" in mock_post.call_args[1]["files"]
+
+    def test_upload_to_presigned_url_with_put_headers(self, api_key, tmp_path):
+        client = ChatClient(api_key)
+        file_path = tmp_path / "file.png"
+        file_path.write_bytes(b"png")
+
+        mock_response = Mock(spec=httpx.Response)
+        mock_response.raise_for_status = Mock()
+
+        with patch("fastgpt_client.client.httpx.put", return_value=mock_response) as mock_put:
+            response = client.upload_to_presigned_url(
+                upload_url="https://s3.example/upload",
+                file_path=file_path,
+                headers={"x-amz-meta-test": "1"},
+            )
+
+        assert response is mock_response
+        mock_put.assert_called_once()
+        assert mock_put.call_args[1]["headers"]["x-amz-meta-test"] == "1"
+        assert mock_put.call_args[1]["headers"]["Content-Type"] == "image/png"
+
+    def test_upload_chat_image_with_fields_gets_preview_url(self, api_key, tmp_path):
+        client = ChatClient(api_key)
+        file_path = tmp_path / "file.png"
+        file_path.write_bytes(b"png")
+
+        with patch.object(client, "_get_chat_file_select_config", return_value={"canSelectImg": True}), \
+            patch.object(client, "presign_chat_file_post_url", return_value={
+                "url": "https://s3.example/upload",
+                "fields": {"key": "chat/file.png"},
+                "maxSize": 100,
+            }) as mock_presign, \
+            patch.object(client, "upload_to_presigned_url") as mock_upload, \
+            patch.object(client, "presign_chat_file_get_url", return_value="https://s3.example/preview.png") as mock_get:
+            result = client.upload_chat_image(
+                appId="app-123",
+                chatId="chat-123",
+                file_path=file_path,
+            )
+
+        assert result == {
+            "type": "img",
+            "name": "file.png",
+            "key": "chat/file.png",
+            "url": "https://s3.example/preview.png",
+            "previewUrl": "https://s3.example/preview.png",
+        }
+        assert mock_presign.call_args[1]["fileSelectConfig"] == {"canSelectImg": True}
+        mock_upload.assert_called_once()
+        mock_get.assert_called_once_with(appId="app-123", key="chat/file.png", outLinkAuthData=None)
+
+
 class TestChatClientGetChatHistories:
     """Test suite for ChatClient.get_chat_histories method."""