Added core.updater module

addons/source-python/packages/source-python/core/updater.py

@@ -0,0 +1,94 @@
+# ../core/updater.py
+
+"""Provides functions to update Source.Python's data files."""
+
+# =============================================================================
+# >> IMPORTS
+# =============================================================================
+# Python Imports
+import hashlib
+
+from zipfile import ZipFile
+from urllib.request import urlopen
+
+# Source.Python Imports
+from paths import DATA_PATH
+from paths import SP_DATA_PATH
+
+
+# =============================================================================
+# >> ALL DECLARATION
+# =============================================================================
+__all__ = (
+    'CHECKSUM_URL', 
+    'DATA_URL', 
+    'DATA_ZIP_FILE', 
+    'download_latest_data',
+    'get_latest_data_checksum',
+    'is_new_data_available', 
+    'unpack_data', 
+    'update_data'
+)
+
+
+# =============================================================================
+# >> GLOBAL VARIABLES
+# =============================================================================
+DATA_ZIP_FILE = DATA_PATH / 'source-python-data.zip'
+CHECKSUM_URL = 'http://data.sourcepython.com/checksum.txt'
+DATA_URL = 'http://data.sourcepython.com/source-python-data.zip'
+
+
+# =============================================================================
+# >> FUNCTIONS
+# =============================================================================
+def get_latest_data_checksum(timeout=3):
+    """Return the MD5 checksum of the latest data from the build server.
+
+    :param float timeout:
+        Number of seconds that need to pass until a timeout occurs.
+    :rtype: str
+    """
+    with urlopen(CHECKSUM_URL, timeout=timeout) as url:
+        return url.read().decode()
+
+def download_latest_data(timeout=3):
+    """Download the latest data from the build server.
+
+    :param float timeout:
+        Number of seconds that need to pass until a timeout occurs.
+    """
+    with urlopen(DATA_URL, timeout=timeout) as url:
+        data = url.read()
+
+    with DATA_ZIP_FILE.open('wb') as f:
+        f.write(data)
+
+def unpack_data():
+    """Unpack ``source-python-data.zip``."""
+    with ZipFile(DATA_ZIP_FILE) as zip:
+        zip.extractall(DATA_PATH)
+
+def update_data(timeout=3):
+    """Download and unpack the latest data from the build server.
+
+    :param float timeout:
+        Number of seconds that need to pass until a timeout occurs.
+    """
+    download_latest_data(timeout)
+    if SP_DATA_PATH.isdir():
+        SP_DATA_PATH.rmtree()
+
+    unpack_data()
+
+def is_new_data_available(timeout=3):
+    """Return ``True`` if new data is available.
+
+    :param float timeout:
+        Number of seconds that need to pass until a timeout occurs.
+    :rtype: bool
+    """
+    if not DATA_ZIP_FILE.isfile():
+        return True
+
+    return DATA_ZIP_FILE.read_hexhash('md5') != get_latest_data_checksum(timeout)