Parse date-/time-range expressions using the Aika library

https://github.com/panodata/aika

Author: amotl

.github/workflows/main.yml

@@ -35,6 +35,11 @@ jobs:
     - name: Acquire sources
       uses: actions/checkout@v3
 
+    - name: Generate locales
+      if: runner.os == 'Linux'
+      run: |
+        sudo apt-get update && sudo apt-get install --yes tzdata locales && sudo locale-gen de_DE.UTF-8
+
     - name: Set up Python
       uses: actions/setup-python@v4
       with:

CHANGES.md

@@ -10,3 +10,4 @@
 - Fix return journey wrt. arrival time
 - Process HAFAS remarks
 - Add colored terminal output
+- Parse date-/time-range expressions using the Aika library

README.md

@@ -19,6 +19,9 @@ and further stops on the trip, and computes travel plan drafts using the [HAFAS]
 rex9 travel --from=Oranienburg --to=Stralsund --stops=Fürstenberg,Mildenberg --when=do-di
 ```
 
+The `--when` argument accepts all date-/time-range expressions as provided by the [Aika]
+package, which currently supports English and German.
+
 
 ## Glossary
 
@@ -46,4 +49,5 @@ poe check
 ```
 
 
+[Aika]: https://github.com/panodata/aika
 [HAFAS]: https://de.wikipedia.org/wiki/HAFAS

pyproject.toml

@@ -47,6 +47,7 @@ classifiers = [
 ]
 
 dependencies = [
+  "aika==0.1",
   "click<=9",
   "colorlog<7",
   "markdown2<3",
@@ -72,6 +73,7 @@ release = [
 ]
 test = [
   "coverage<8",
+  "freezegun<1.3",
   "pytest<8",
 ]
 [tool.setuptools]

rex9/core.py

@@ -6,13 +6,13 @@
 import typing as t
 from textwrap import indent
 
+from aika import DaterangeExpression
 from pyhafas import HafasClient
 from pyhafas.profile import DBProfile
 from pyhafas.types.fptf import Remark
 
 from rex9.model import TimeMode, TravelJourney, TravelJourneySegment, TravelPlan, TravelPlanSegment
-from rex9.util.cli import split_list
-from rex9.util.date import format_date_weekday, format_time, next_date_by_weekday
+from rex9.util.date import format_date_weekday, format_time
 from rex9.util.format import CliFormatter as cf
 from rex9.util.pyhafas import query_for
 
@@ -41,11 +41,8 @@ def make_travelplan(origin: str, destination: str, stops: t.List[str], when: str
     location_remote = client.locations(destination)[0]
 
     # Resolve departure and arrival times of home and remote locations.
-    on_begin, on_end = split_list(when, delimiter="-")
-    date_begin = next_date_by_weekday(on_begin)
-    date_end = next_date_by_weekday(on_end, start=date_begin)
-    datetime_begin = dt.datetime.combine(date_begin, DEFAULT_DEPARTURE_TIME)
-    datetime_end = dt.datetime.combine(date_end, DEFAULT_ARRIVAL_TIME)
+    dr = DaterangeExpression(default_start_time=DEFAULT_DEPARTURE_TIME, default_end_time=DEFAULT_ARRIVAL_TIME)
+    datetime_begin, datetime_end = dr.parse(when)
 
     # Report an intermediate summary.
     logger.info(

rex9/util/date.py

@@ -4,34 +4,6 @@
 import datetime as dt
 import typing as t
 
-import dateutil.relativedelta as dtrel
-
-
-class WeekdayMap:
-    days_en = ["MO", "TU", "WE", "TH", "FR", "SA", "SU"]
-    days_de = ["MO", "DI", "MI", "DO", "FR", "SA", "SO"]
-
-    def __init__(self):
-        self.weekdays = {}
-        for index, day in enumerate(self.days_en):
-            self.weekdays[day] = dtrel.weekday(index)
-        for index, day in enumerate(self.days_de):
-            self.weekdays[day] = dtrel.weekday(index)
-
-    def find(self, label: str):
-        for key, value in self.weekdays.items():
-            if key.lower().startswith(label.lower()):
-                return value
-        raise KeyError(f"Weekday not found: {label}")
-
-
-def next_date_by_weekday(weekday: str, start=None):
-    start = start or dt.date.today()
-    weekday_map = WeekdayMap()
-    weekday_dtrel = weekday_map.find(weekday)
-    delta = dtrel.relativedelta(days=1, weekday=weekday_dtrel)
-    return start + delta
-
 
 def format_date_weekday(datetime: dt.datetime):
     return f"{datetime} ({datetime.strftime('%A')})"

tests/test_util_date.py

@@ -3,22 +3,47 @@
 
 import datetime as dt
 
-import pytest
-
-from rex9.util.date import next_date_by_weekday
-
-
-def test_weekdaymap_de():
-    date_value = next_date_by_weekday("do")
-    assert isinstance(date_value, dt.date)
-
-
-def test_weekdaymap_en():
-    date_value = next_date_by_weekday("su")
-    assert isinstance(date_value, dt.date)
-
-
-def test_weekdaymap_fail():
-    with pytest.raises(KeyError) as ex:
-        next_date_by_weekday("foo")
-    assert ex.match("Weekday not found: foo")
+from aika import DaterangeExpression
+from freezegun import freeze_time
+
+TESTDRIVE_DATETIME = "2023-08-17T23:03:17+0200"
+
+
+@freeze_time(TESTDRIVE_DATETIME)
+def test_parse_daterange_relative_months():
+    dr = DaterangeExpression(
+        default_start_time=dt.time(hour=9),
+        default_end_time=dt.time(hour=17),
+    )
+    assert (
+        dr.parse("next March")
+        == dr.parse("im März")
+        == (
+            dt.datetime(2023, 3, 1, 9, 0, 0),
+            dt.datetime(2023, 3, 31, 17, 0, 0),
+        )
+    )
+    assert (
+        dr.parse("July to December")
+        == dr.parse("Juli bis Dezember")
+        == (
+            dt.datetime(2023, 7, 1, 9, 0, 0),
+            dt.datetime(2023, 12, 31, 17, 0, 0),
+        )
+    )
+
+
+@freeze_time(TESTDRIVE_DATETIME)
+def test_parse_daterange_relative_weekdays():
+    dr = DaterangeExpression(
+        default_start_time=dt.time(hour=9),
+        default_end_time=dt.time(hour=17),
+    )
+    assert (
+        dr.parse("Sat - Tue")
+        == dr.parse("Sa-Di")
+        == (
+            dt.datetime(2023, 8, 19, 9, 0, 0),
+            dt.datetime(2023, 8, 22, 17, 0, 0),
+        )
+    )