Added tests, installed pngquant in GA

Author: facundobatista

.github/workflows/pythonapp.yml

@@ -25,6 +25,7 @@ jobs:
         python-version: ${{ matrix.python-version }}
     - name: Install dependencies
       run: |
+        sudo apt install pngquant
         python -m pip install --upgrade pip
         pip install -r requirements-dev.txt
     - name: Test with pytest

src/images/download.py

@@ -36,6 +36,9 @@
         'Ubuntu/8.10 (intrepid) Firefox/3.0.5')
 }
 
+# seconds to sleep before each retrial when downloading (starting from the end)
+RETRIES = [5, 1, .3]
+
 # Turning off the PIL debug logs as are too noisy.
 logging.getLogger("PIL").setLevel(logging.INFO)
 
@@ -86,16 +89,14 @@ def _download(url, fullpath):
 def download(data):
     """Download image from url, retry on error."""
     url, fullpath = data
+    retries = RETRIES.copy()
 
     basedir, _ = os.path.split(fullpath)
     # call it directly with exist_ok=True; it's better than verify if it exists
     # and then create, as if it's done in two lines a race condition may happen
     # (this function internally just catches the error)
     os.makedirs(basedir, exist_ok=True)
 
-    # seconds to sleep before each retrial (starting from the end)
-    retries = [5, 1, .3]
-
     while True:
         try:
             _download(url, fullpath)

tests/test_images_download.py

@@ -0,0 +1,127 @@
+# Copyright 2021 CDPedistas (see AUTHORS.txt)
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU General Public License version 3, as published
+# by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranties of
+# MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR
+# PURPOSE.  See the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# For further info, check  https://github.com/PyAr/CDPedia/
+
+import shutil
+from unittest.mock import patch
+
+from src.images.download import optimize_png, download, FetchingError
+
+import pytest
+
+
+@pytest.fixture
+def image_config(tmp_path):
+    def f(name):
+        img_test_name = 'tests/fixtures/image_to_optimize.png'
+        test_path = tmp_path / name
+        shutil.copy(img_test_name, str(test_path))
+        init_size = test_path.stat().st_size
+        return test_path, init_size
+    yield f
+
+
+@pytest.mark.parametrize('filename', [
+    'image.png',  # simple
+    'Image.PNG',  # uppercase
+    'moño.png',  # unicode
+    'the image.png',  # spaces
+])
+def test_pngquant_optimize(image_config, filename):
+    img_path, init_size = image_config(filename)
+    optimize_png(str(img_path), init_size, init_size)
+    final_size = img_path.stat().st_size
+    assert init_size > final_size
+
+
+def test_download_ok(tmp_path):
+    test_path = tmp_path / 'foo' / 'bar' / 'baz.png'
+
+    with patch('src.images.download.optimize_image') as _optimize_mock:
+        with patch('src.images.download._download') as _download_mock:
+            # real download will be ok, no need to patch RETRIES
+            _download_mock.return_value = None
+
+            download(('test-url', str(test_path)))
+
+    # check directory were prepared ok
+    assert test_path.parent.exists()
+
+    # download and optimization was called ok
+    _download_mock.assert_called_once_with('test-url', str(test_path))
+    _optimize_mock.assert_called_once_with(str(test_path))
+
+
+@pytest.mark.parametrize('extension', [
+    '.svg',
+    '.gif',
+    '.Svg',
+    '.Gif',
+    '.SVG',
+    '.GIF',
+])
+def test_download_no_optimization(extension, tmp_path):
+    test_path = tmp_path / 'foo' / 'bar' / ('baz.' + extension)
+
+    with patch('src.images.download.optimize_image') as _optimize_mock:
+        with patch('src.images.download._download') as _download_mock:
+            # real download will be ok, no need to patch RETRIES
+            _download_mock.return_value = None
+
+            download(('test-url', str(test_path)))
+
+    # optimization was NOT called
+    _optimize_mock.assert_not_called()
+
+
+def test_download_retry_ok(tmp_path):
+    test_path = tmp_path / 'foo' / 'bar' / 'baz.png'
+
+    with patch('src.images.download.optimize_image'):
+        with patch('src.images.download._download') as _download_mock:
+            with patch('src.images.download.RETRIES', [0]):
+                # first time ends with error, second ok
+                _download_mock.side_effect = [
+                    ValueError('pumba'),
+                    None,
+                ]
+                download(('test-url', str(test_path)))
+
+    # check directory were prepared ok
+    assert test_path.parent.exists()
+
+    # download was called twice
+    assert _download_mock.call_count == 2
+
+
+def test_download_problems(tmp_path):
+    test_path = tmp_path / 'foo' / 'bar' / 'baz.png'
+
+    with patch('src.images.download.optimize_image'):
+        with patch('src.images.download._download') as _download_mock:
+            with patch('src.images.download.RETRIES', [0]):
+                # always in error
+                _download_mock.side_effect = [
+                    ValueError('pumba'),
+                    ValueError('pumba'),
+                ]
+                with pytest.raises(FetchingError):
+                    download(('test-url', str(test_path)))
+
+    # check directory were prepared ok
+    assert test_path.parent.exists()
+
+    # download was called twice
+    assert _download_mock.call_count == 2