filter: add new time_delta filter

* Calculate datetime string based upon time delta
  provided by user

Signed-off-by: Abhijeet Kasurde <[email protected]>

Author: Akasurde

plugins/filter/time.py

@@ -7,6 +7,9 @@
 __metaclass__ = type
 
 import re
+
+from datetime import timedelta, datetime
+
 from ansible.errors import AnsibleFilterError
 
 
@@ -130,7 +133,33 @@ def to_years(human_time, **kwargs):
     return to_time_unit(human_time, 'y', **kwargs)
 
 
-class FilterModule(object):
+def time_delta(date_time, **kwargs):
+    ''' Return datetime after calculating time delta '''
+    if not isinstance(date_time, str):
+        raise AnsibleFilterError('time_delta accepts datetime in string format')
+    date_format = "%Y-%m-%d %H:%M:%S"
+    if 'date_format' in kwargs:
+        date_format = kwargs.get('date_format')
+
+    delta = {
+        'days': kwargs.get('days', 0),
+        'microseconds': kwargs.get('microseconds', 0),
+        'milliseconds': kwargs.get('milliseconds', 0),
+        'minutes': kwargs.get('minutes', 0),
+        'hours': kwargs.get('hours', 0),
+        'weeks': kwargs.get('weeks', 0),
+    }
+    try:
+        source_date = datetime.strptime(date_time, date_format)
+    except ValueError:
+        raise AnsibleFilterError(
+            f'Failed to parse provided string into datetime format "{date_format}" provided.'
+        )
+
+    return str(source_date + timedelta(**delta))
+
+
+class FilterModule:
     ''' Ansible time jinja2 filters '''
 
     def filters(self):
@@ -144,6 +173,7 @@ def filters(self):
             'to_weeks': to_weeks,
             'to_months': to_months,
             'to_years': to_years,
+            'time_delta': time_delta,
         }
 
         return filters

plugins/filter/time_delta.yml

@@ -0,0 +1,75 @@
+---
+# Copyright: Contributors to the Ansible project
+# GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+DOCUMENTATION:
+  name: time_delta
+  short_description: Calculate datetime based upon the user given timedelta
+  version_added: 10.6.0
+  description:
+    - Calculate a new date/time by applying a time delta to a given datetime string.
+  options:
+    _input:
+      description:
+        - The time string to calculate timedelta from.
+        - The format should match the O(date_format) unless specified otherwise.
+      type: string
+      required: true
+    date_format:
+      description:
+        - The format to parse the given input.
+        - Defaults to "%Y-%m-%d %H:%M:%S".
+        - You can specify your own format if the datetime string is in a different format.
+        - See Python 3 datetime format codes for more information.
+      type: string
+    days:
+      type: integer
+      description:
+        - The number of days to add or subtract.
+        - Default is 0.
+    microseconds:
+      type: integer
+      description:
+        - The number of microseconds to add or subtract.
+        - Default is 0.
+    milliseconds:
+      type: integer
+      description:
+        - The number of milliseconds to add or subtract.
+        - Default is 0.
+    minutes:
+      type: integer
+      description:
+        - The number of minutes to add or subtract.
+        - Default is 0.
+    hours:
+      type: integer
+      description:
+        - The number of hours to add or subtract.
+        - Default is 0.
+    weeks:
+      type: integer
+      description:
+        - The number of weeks to add or subtract.
+        - Default is 0.
+  author:
+    - Abhijeet Kasurde (@Akasurde)
+
+EXAMPLES: |
+
+  tomorrow: "{{ '2025-03-12 18:00:00' | community.general.time_delta(days=1, date_format='%Y-%m-%d %H:%M:%S') }}"
+  # => "2025-03-13T18:00:00"
+
+  yesterday: "{{ '2025-03-12 18:00:00' | community.general.time_delta(days=-1) }}"
+  # => "2025-03-11T18:00:00"
+
+  a_month_ago: "{{ '2025/03/12' | community.general.time_delta(days=-30, date_format='%Y/%m/%d') }}"
+  # => "2025-02-10T00:00:00"
+
+RETURN:
+  _value:
+    description:
+      - Date string after applying the delta in ISO 8601 format.
+      - Raises AnsibleFilterError on failing to parse the datetime string.
+    type: string

tests/integration/targets/filter_time/tasks/main.yml

@@ -113,3 +113,12 @@
     that:
       - res is failed
       - "'to_time_unit() got unknown keyword arguments' in res.msg"
+
+- name: test time_delta filter
+  assert:
+    that:
+      - "('2025-03-12 18:00:00' | community.general.time_delta(days=-1)) == '2025-03-11 18:00:00'"
+      - "('2025-03-12 18:00:00' | community.general.time_delta(minutes=-60)) == '2025-03-12 17:00:00'"
+      - "('2025-03-12 18:00:00' | community.general.time_delta(hours=-1)) == '2025-03-12 17:00:00'"
+      - "('2025-03-12 18:00:00' | community.general.time_delta(weeks=-1)) == '2025-03-05 18:00:00'"
+      - "('2025/03/12' | community.general.time_delta(days=-30, date_format='%Y/%m/%d')) == '2025-02-10 00:00:00'"