added missing py files

[pywienerlinien] / gotovienna / update.py

diff --git a/gotovienna/update.py b/gotovienna/update.py
new file mode 100644 (file)
index 0000000..00f8c23
--- /dev/null
+++ b/gotovienna/update.py
@@ -0,0 +1,43 @@
+from urllib2 import urlopen
+from hashlib import md5
+from datetime import datetime
+import os
+from os import path
+from config import config
+
+CONFIGDIR = path.expanduser('~/.gotovienna')
+STATIONFILENAME = path.join(CONFIGDIR, 'stations.db')
+URLPREFIX = 'http://www.logic.at/people/kelvan/python/gotovienna/downloads/%s'
+REMOTEFILE = 'stations.db'
+REMOTEHASH = 'stations.md5'
+
+def compare_hash(md5sum, fn):
+    localmd5 = md5()
+    md5sum = md5sum.split()[0]
+
+    if not path.exists(fn):
+        # File doesn't exist
+        return False
+
+    with open(fn,'rb') as f: 
+        for chunk in iter(lambda: f.read(8192), ''): 
+             localmd5.update(chunk)
+    return localmd5.hexdigest() == md5sum
+
+def check_stations_update():
+    """ Check for new version of stations.db
+        return True if new version available
+        return False if not
+        raise exception if unable to check for new version
+    """
+    remote_hash = urlopen(URLPREFIX % REMOTEHASH).read()
+    return not compare_hash(remote_hash, STATIONFILENAME)
+
+def update_stations():
+    if not path.exists(CONFIGDIR):
+        os.mkdir(CONFIGDIR)
+    remote = urlopen(URLPREFIX % REMOTEFILE)
+    with open(STATIONFILENAME, 'wb') as f:
+        f.write(remote.read())
+    config.setLastStationsUpdate(datetime.now().strftime('%c'))
+    return True