Make the polling delay configurable (#19)

Dockerfile

@@ -4,22 +4,21 @@ FROM debian:buster
 # Maintainer
 LABEL maintainer "Alexander Graf <alex@otherguy.io>"
 
-# Build arguments
-ARG VCS_REF=master
-ARG BUILD_DATE=""
-
-# http://label-schema.org/rc1/
-LABEL org.label-schema.schema-version "1.0"
-LABEL org.label-schema.name           "Dropbox"
-LABEL org.label-schema.build-date     "${BUILD_DATE}"
-LABEL org.label-schema.description    "Standalone Dropbox client"
-LABEL org.label-schema.vcs-url        "https://github.com/otherguy/docker-dropbox"
-LABEL org.label-schema.vcs-ref        "${VCS_REF}"
-
 # Required to prevent warnings
 ARG DEBIAN_FRONTEND=noninteractive
 ARG DEBCONF_NONINTERACTIVE_SEEN=true
 
+# Change working directory
+WORKDIR /opt/dropbox/Dropbox
+
+# Not really required for --net=host
+EXPOSE 17500
+
+# Set language
+ENV LANG     "en_US.UTF-8"
+ENV LANGUAGE "en_US.UTF-8"
+ENV LC_ALL   "en_US.UTF-8"
+
 # Install prerequisites
 RUN apt-get update \
  && apt-get install -y --no-install-recommends apt-transport-https ca-certificates curl gnupg2 \
@@ -33,21 +32,10 @@ RUN mkdir -p /opt/dropbox /opt/dropbox/.dropbox /opt/dropbox/Dropbox \
  && useradd --home-dir /opt/dropbox --comment "Dropbox Daemon Account" --user-group --shell /usr/sbin/nologin dropbox \
  && chown -R dropbox:dropbox /opt/dropbox
 
-# Set language
-ENV LANG     "en_US.UTF-8"
-ENV LANGUAGE "en_US.UTF-8"
-ENV LC_ALL   "en_US.UTF-8"
-
 # Generate locales
 RUN sed --in-place '/en_US.UTF-8/s/^# //' /etc/locale.gen \
  && locale-gen
 
-# Change working directory
-WORKDIR /opt/dropbox/Dropbox
-
-# Not really required for --net=host
-EXPOSE 17500
-
 # https://help.dropbox.com/installs-integrations/desktop/linux-repository
 RUN apt-key adv --keyserver keyserver.ubuntu.com --recv-keys FC918B335044912E \
  && add-apt-repository 'deb http://linux.dropbox.com/debian buster main' \
@@ -74,6 +62,21 @@ RUN mkdir -p /opt/dropbox/bin/ /tmp \
 # Create volumes
 VOLUME ["/opt/dropbox/.dropbox", "/opt/dropbox/Dropbox"]
 
+# Build arguments
+ARG VCS_REF=master
+ARG BUILD_DATE=""
+
+# http://label-schema.org/rc1/
+LABEL org.label-schema.schema-version "1.0"
+LABEL org.label-schema.name           "Dropbox"
+LABEL org.label-schema.build-date     "${BUILD_DATE}"
+LABEL org.label-schema.description    "Standalone Dropbox client"
+LABEL org.label-schema.vcs-url        "https://github.com/otherguy/docker-dropbox"
+LABEL org.label-schema.vcs-ref        "${VCS_REF}"
+
+# Configurable sleep delay
+ENV SLEEP_DELAY=5
+
 # Install init script and dropbox command line wrapper
 COPY docker-entrypoint.sh /
 

README.md

@@ -156,6 +156,11 @@ files. Defaults to `1000`.
 If set to `true`, skips updating the Dropbox app on container startup. _Note:_ This is not very reliable
 because the Dropbox daemon will still try to update itself even if this is set to `true`.
 
+- `SLEEP_DELAY`
+Needs to be set to a positive integer value. The Dropbox daemon is polled for its status at regular intervals,
+which can be configured to reduce load on the system. This is the number in seconds to wait between polling the
+Dropbox daemon. Defaults to `5`.
+
 ### Exposed Volumes
 
 - `/opt/dropbox/Dropbox`

docker-entrypoint.sh

@@ -31,6 +31,11 @@ if [ -z "$(grep ":${DROPBOX_GID}:" /etc/group)" ]; then
   groupadd -g $DROPBOX_GID dropbox
 fi
 
+if [[ ! "${SLEEP_DELAY}" =~ ^[0-9]+$ ]]; then
+  echo "SLEEP_DELAY not set to a valid number, defaulting to 5!"
+  export SLEEP_DELAY=5
+fi
+
 # Set dropbox account's UID/GID.
 usermod -u ${DROPBOX_UID} -g ${DROPBOX_GID} --non-unique dropbox > /dev/null 2>&1
 
@@ -101,5 +106,5 @@ sleep 5
 while kill -0 ${DROPBOX_PID} 2> /dev/null; do
   [ -d "/proc/${DROPBOX_PID}" ] && [ -f "/opt/dropbox/.dropbox/info.json" ] && gosu dropbox dropbox status
   /usr/bin/find /tmp -maxdepth 1 -type d -mtime +1 -exec rm -rf {} \;
-  /bin/sleep 1
+  /bin/sleep ${SLEEP_DELAY}
 done