Day three exercise

Author: dwaler

days/01-03-datetimes/code/logs.py

@@ -0,0 +1,44 @@
+from datetime import datetime
+import os
+import urllib.request
+import re
+
+
+SHUTDOWN_EVENT = 'Shutdown initiated'
+
+# prep: read in the logfile
+tmp = os.getenv("TMP", "/tmp")
+logfile = os.path.join(tmp, 'log')
+urllib.request.urlretrieve(
+    'https://bites-data.s3.us-east-2.amazonaws.com/messages.log',
+    logfile
+)
+
+with open(logfile) as f:
+    loglines = f.readlines()
+
+# for you to code:
+
+def convert_to_datetime(line):
+    """TODO 1:
+       Extract timestamp from logline and convert it to a datetime object.
+       For example calling the function with:
+       INFO 2014-07-03T23:27:51 supybot Shutdown complete.
+       returns:
+       datetime(2014, 7, 3, 23, 27, 51)
+    """
+    timestamp = re.split('\\s+', line)[1]
+    return datetime.fromisoformat(timestamp)
+
+
+def time_between_shutdowns(loglines):
+    """TODO 2:
+       Extract shutdown events ("Shutdown initiated") from loglines and
+       calculate the timedelta between the first and last one.
+       Return this datetime.timedelta object.
+    """
+    all_shutdowns = [line for line in loglines if SHUTDOWN_EVENT in line]
+    time_between_shutdowns = convert_to_datetime(all_shutdowns[1]) - convert_to_datetime(all_shutdowns[0])
+    return time_between_shutdowns
+
+print("Time between shutdowns:", time_between_shutdowns(loglines))