Moved unzip_data to standalone file

data/bad.zip

@@ -0,0 +1 @@
+This is not a valid zip file

src/datapipeline.py

@@ -1,25 +1,10 @@
 """
-Functions to ingest and process data
+Modularized Data pipeline to form DAGs in the future
 """
-import zipfile
-
 from .download_data import ingest_data
-
-
-def unzip_file():
-    """
-    Function to unzip the downloaded data
-    """
-    zip_filename ='data/data.zip'
-    extract_to = 'data/'
-    try:
-        with zipfile.ZipFile(zip_filename, 'r') as zip_ref:
-            zip_ref.extractall(extract_to)
-        print(f"File {zip_filename} successfully unzipped to {extract_to}")
-    except zipfile.BadZipFile:
-        print(f"Failed to unzip {zip_filename}")
+from .unzip_data import unzip_file
 
 
 if __name__ == "__main__":
     ZIPFILE_PATH = ingest_data("https://archive.ics.uci.edu/static/public/352/online+retail.zip")
-    unzip_file()
+    UNZIPPED_FILE = unzip_file(ZIPFILE_PATH, 'data/')

src/download_data.py

@@ -8,6 +8,10 @@
 def ingest_data(file_url=DEFAULT_FILE_URL):
     """
     Function to download file from URL
+    Args:
+        file_url: URL of the file, A default is used if not specified
+    Returns:
+        zipfile_path: The zipped file path to the data
     """
     # Send an HTTP GET request to the URL
     response = requests.get(file_url, timeout=30)

src/unzip_data.py

@@ -0,0 +1,27 @@
+"""
+Function to unzip data and make it available
+"""
+import zipfile
+
+ZIP_FILENAME ='data/data.zip'
+EXTRACT_TO = 'data/'
+
+def unzip_file(zip_filename=ZIP_FILENAME, extract_to=EXTRACT_TO):
+    """
+    Function to unzip the downloaded data
+    Args:
+      zip_filename: zipfile path, a default is used if not specified
+      extract_to: Path where the unzipped and extracted data is available
+    Returns:
+      extract_to: filepath where the data is available
+    """
+    try:
+        with zipfile.ZipFile(zip_filename, 'r') as zip_ref:
+            zip_ref.extractall(extract_to)
+        print(f"File {zip_filename} successfully unzipped to {extract_to}")
+    except zipfile.BadZipFile:
+        print(f"Failed to unzip {zip_filename}")
+    return extract_to
+
+if __name__ == "__main__":
+    UNZIPPED_FILE = unzip_file(ZIP_FILENAME, EXTRACT_TO)

test/test_datapipeline.py

@@ -1,27 +1,3 @@
 """
 Tests for datapipeline functions
 """
-from src import datapipeline
-
-def test_unzip_file(mocker):
-    """
-    Tests for unzip()
-    """
-
-    # arrange:
-    # mocked dependencies
-
-    mock_zipfile = mocker.MagicMock(name='ZipFile')
-    mocker.patch('src.datapipeline.zipfile.ZipFile', new=mock_zipfile)
-
-    mock_print = mocker.MagicMock(name='print')
-    mocker.patch('src.datapipeline.print', new=mock_print)
-
-    mock_exception = mocker.MagicMock(name='Exception')
-    mocker.patch('src.datapipeline.Exception', new=mock_exception)
-
-    # act: invoking the tested code
-    datapipeline.unzip_file()
-
-    # assert:
-    mock_exception.assert_not_called()

test/test_unzip_data.py

@@ -0,0 +1,53 @@
+"""
+Function to test the unzip_data functions
+"""
+from src import unzip_data
+
+# Define constants or variables for testing
+ZIP_FILENAME = 'data/data.zip'
+EXTRACT_TO = 'data/'
+BAD_ZIP_FILENAME = 'data/bad.zip'
+
+def test_unzip_file_successful(tmp_path):
+    """
+      Test for successful unzipping
+    """
+    # Create a temporary directory for testing
+    test_dir = tmp_path / "test_dir"
+    test_dir.mkdir()
+
+    # Copy the sample zip file to the temporary directory
+    zip_file = tmp_path / "data.zip"
+    with open(ZIP_FILENAME, "rb") as src, open(zip_file, "wb") as dst:
+        dst.write(src.read())
+
+    # Call the function
+    result = unzip_data.unzip_file(zip_file, test_dir)
+
+    print(result)
+
+    # Check if the function returned the expected extract_to path
+    assert result == test_dir
+
+
+def test_unzip_file_bad_zip(tmp_path, capsys):
+    """
+      Test for handling a bad zip file
+    """
+    # Create a temporary directory for testing
+    test_dir = tmp_path / "test_dir"
+    test_dir.mkdir()
+
+    # Create a bad zip file in the temporary directory
+    with open(BAD_ZIP_FILENAME, "wb") as file:
+        file.write(b"This is not a valid zip file")
+
+    # Call the function with the bad zip file
+    result = unzip_data.unzip_file(BAD_ZIP_FILENAME, test_dir)
+
+    # Check if the function returned the extract_to path
+    assert result == test_dir
+
+    # Check if the function printed the appropriate error message
+    captured = capsys.readouterr()
+    assert "Failed to unzip" in captured.out