add time ago on recent items

+ move to waitress wsgi server
+ refactor dates utils
+ create locustfile for stress test

app/utils/dates.py

@@ -1,9 +1,20 @@
 import pendulum
-from datetime import datetime
+from datetime import datetime, timedelta
 
 _format = "%Y-%m-%d %H:%M:%S"
 
 
+def timestamp_from_days_ago(days_ago: int):
+    """
+    Returns a timestamp from a number of days ago.
+    """
+    current_datetime = datetime.now()
+    delta = timedelta(days=days_ago)
+    past_timestamp = current_datetime - delta
+
+    return int(past_timestamp.timestamp())
+
+
 def create_new_date(date: datetime = None) -> str:
     """
     Creates a new date and time string in the format of "YYYY-MM-DD HH:MM:SS"
@@ -15,18 +26,26 @@ def create_new_date(date: datetime = None) -> str:
     return date.strftime(_format)
 
 
-def date_string_to_time_passed(prev_date: str) -> str:
+def timestamp_to_time_passed(timestamp: str):
     """
-    Converts a date string to time passed. e.g. 2 minutes ago, 1 hour ago, yesterday, 2 days ago, 2 weeks ago, etc.
+    Converts a timestamp to time passed. e.g. 2 minutes ago, 1 hour ago, yesterday, 2 days ago, 2 weeks ago, etc.
     """
     now = datetime.now().timestamp()
-    then = datetime.strptime(prev_date, _format).timestamp()
+    then = datetime.fromtimestamp(int(timestamp)).timestamp()
 
     diff = now - then
     now = pendulum.now()
     return now.subtract(seconds=diff).diff_for_humans()
 
 
+def date_string_to_time_passed(prev_date: str) -> str:
+    """
+    Converts a date string to time passed. e.g. 2 minutes ago, 1 hour ago, yesterday, 2 days ago, 2 weeks ago, etc.
+    """
+    then = datetime.strptime(prev_date, _format).timestamp()
+    return timestamp_to_time_passed(then)
+
+
 def seconds_to_time_string(seconds):
     """
     Converts seconds to a time string. e.g. 1 hour 2 minutes, 1 hour 2 seconds, 1 hour, 1 minute 2 seconds, etc.