Add unit tests for extract_and_translate function

app/backend_gcf/tests/test_main.py

@@ -0,0 +1,40 @@
+import pytest
+from unittest.mock import patch, MagicMock # To mock external API calls
+from flask import Flask, request # To simulate HTTP requests
+from io import BytesIO
+
+# Import the function from main.py
+from backend_gcf.main import extract_and_translate
+
+@pytest.fixture
+def app():
+    """ Fixture for Flask app context, for creating HTTP requests """
+    app = Flask(__name__)
+    return app
+
+# Use patch to replace the Google clients with mock objects
+@patch('backend_gcf.main.vision_client')
+@patch('backend_gcf.main.translate_client')
+def test_extract_and_translate_with_posted_image(mock_translate_client, mock_vision_client, app: Flask):
+    with app.test_request_context(
+        method='POST',
+        data={
+            'uploaded': (BytesIO(b'sample image data'), 'test_image.jpg'),
+            'to_lang': 'en'
+        },
+        content_type='multipart/form-data'
+    ):
+        # Mock Vision API response
+        mock_vision_client.text_detection.return_value = MagicMock(
+            text_annotations=[MagicMock(description="Put a glass of rice and three glasses of water in a saucepan")]
+        )
+
+        # Mock Translate API response
+        mock_translate_client.detect_language.return_value = {"language": "uk"}
+        mock_translate_client.translate.return_value = {"translatedText": "Put a glass of rice and three glasses of water in a saucepan"}
+
+        # Call the function
+        response = extract_and_translate(request)
+
+        # Check the result
+        assert response == "Put a glass of rice and three glasses of water in a saucepan"

requirements.txt

@@ -29,6 +29,7 @@ proto-plus==1.23.0
 protobuf==4.25.3
 pyasn1==0.6.0
 pyasn1_modules==0.4.0
+pytest
 requests==2.32.3
 rsa==4.9
 urllib3==2.2.1