Changing the Timezone to JST on Alpine Linux

Two Implementation Methods

RUN apk --no-cache add tzdata \
  && cp /usr/share/zoneinfo/Asia/Tokyo /etc/localtime \
  && apk del tzdata

Alternatively

ENV TZ=Asia/Tokyo
RUN apk --no-cache add tzdata

Choose one.

Combining the first method with ENV TZ= does not work well.

Verification Method

Check if the date command returns JST.

$ date
Wed Feb 10 09:45:26 JST 2021

Difference

The latter method leaves all time zones within the image.

The size is approximately 3.3 MB.

If your application uses time zones, the latter method is preferable.

Verification Method in Django

./manage.py shell

>>> from django.utils import timezone
>>> timezone.now()
>>> timezone.now().hour