Sample for alpine with timezone in Golang

alpine is small image, but golang:x.x.x-alpine is too big.
Golang's single binary and Docker's multi stage build solves problem with image size,
But another problem with the timezone occurs.

When you call time.LoadLocation(zone), an error occurs.
e.g.

$ make run_alpine
panic: open /usr/local/go/lib/time/zoneinfo.zip: no such file or directory

goroutine 1 [running]:
main.main()
        /go/src/github.com/takecy/tz/main.go:11 +0x22b
make: *** [run_alpine] Error 2

You can solve this problem by adding the following to Dockerfile.

RUN apk --no-cache add tzdata

$ make run_alpine_tz
utc:2017-10-24 05:50:30.540154873 +0000 UTC m=+0.000416296
jst:2017-10-24 14:50:30.540154873 +0900 JST

Image size is increased about 1.5MB.
This is acceptable to me.

Image size

takecy/tz-alpine                                                latest              d9000684ec07        6 minutes ago       5.91MB
takecy/tz-alpine-tz                                             latest              2edd086d69e0        10 minutes ago      7.23MB
takecy/tz                                                       latest              95d22869b20b        11 minutes ago      272MB