Add timezone feature

Dockerfile

@@ -1,3 +1,4 @@
+# Based on Debian
 FROM debian:buster
 
 # Maintainer
@@ -16,7 +17,8 @@ LABEL org.label-schema.vcs-url        "https://github.com/otherguy/docker-dropbo
 LABEL org.label-schema.vcs-ref        "${VCS_REF}"
 
 # Required to prevent warnings
-ENV DEBIAN_FRONTEND noninteractive
+ARG DEBIAN_FRONTEND=noninteractive
+ARG DEBCONF_NONINTERACTIVE_SEEN=true
 
 # Install prerequisites
 RUN apt-get update \

README.md

@@ -28,6 +28,7 @@ This is the full command to start the Dropbox container. All volumes, environmen
 are explained in the sections below.
 
     $ docker run --detach -it --restart=always --name=dropbox \
+      -e "TZ=$(readlink /etc/localtime | sed 's#/var/db/timezone/zoneinfo/##')" \
       -e DROPBOX_UID=$(id -u) \
       -e DROPBOX_GID=$(id -g) \
       -v "/path/to/local/settings:/opt/dropbox/.dropbox" \
@@ -49,6 +50,29 @@ The example below uses `id -u` and `id -g` to retrieve the current user's user i
       -v "/path/to/local/dropbox:/opt/dropbox/Dropbox" \
       [...]
       otherguy/dropbox:latest
+
+### Time Zones
+
+It is also highly recommended to pass your local timezone settings into the container. This fixes the problem
+of the host being on local time zone and container defaulting to `UTC` timezone. Dropbox is not checking time
+zones when comparing file timestamps, leading to overwritten files and data loss.
+
+You can pass your local timezone as an environment variable to the container: `-e "TZ=Australia/Brisbane"`
+
+If you're on Linux 🐧, you can mount your `/etc/timezone` and `/etc/localtime` files into the container instead.
+
+    $ docker run --name=dropbox \
+      -v "/etc/timezone:/etc/timezone" \
+      -v "/etc/localtime:/etc/localtime" \
+      [...]
+      otherguy/dropbox:latest
+
+For everyone else, especially users on macOS, getting your current timezone and passing it into the container
+as an environment variable, is the simplest way:
+
+    $ docker run --name=dropbox \
+      -e "TZ=$(readlink /etc/localtime | sed 's#/var/db/timezone/zoneinfo/##')"
+      [...]
       otherguy/dropbox:latest
 
 ### Enable LAN Sync
@@ -125,3 +149,7 @@ Originally forked from [`janeczku/dropbox`](https://hub.docker.com/r/janeczku/dr
 ## 🚧 Contributing
 
 Bug reports and pull requests are welcome on GitHub at [`otherguy/docker-dropbox`](https://github.com/otherguy/docker-dropbox).
+
+## ♥️ Acknowledgements
+
+- [Tony Pan](https://github.com/tcpan) for [`#3`](https://github.com/otherguy/docker-dropbox/pull/3)

docker-entrypoint.sh

@@ -1,6 +1,19 @@
 #!/bin/bash
 # This script is a fork of https://github.com/excelsiord/docker-dropbox
 
+# Set TZ if not provided with enviromental variable.
+if [ -z "${TZ}" ]; then
+  export TZ="$(cat /etc/timezone)"
+else
+  if [ ! -f "/usr/share/zoneinfo/${TZ}" ]; then
+      echo "The timezone '${TZ}' is unavailable!"
+      exit 1
+  fi
+
+  echo "${TZ}" > /etc/timezone
+  ln -fs "/usr/share/zoneinfo/${TZ}" /etc/localtime
+fi
+
 # Set UID/GID if not provided with enviromental variable(s).
 if [ -z "${DROPBOX_UID}" ]; then
   export DROPBOX_UID=$(/usr/bin/id -u dropbox)
@@ -73,6 +86,10 @@ echo ""
 # Set umask
 umask 002
 
+# Print timezone
+echo "Using $(cat /etc/timezone) timezone ($(date +%H:%M:%S) local time)"
+dpkg-reconfigure --frontend noninteractive tzdata
+
 echo "Starting dropboxd ($(cat /opt/dropbox/bin/VERSION))..."
 exec gosu dropbox "$@" &
    pid="$!"