Helper container to pass forwarded port to Deluge

Dockerfile

FROM alpine:latest
RUN echo "http://dl-cdn.alpinelinux.org/alpine/edge/testing/" >> /etc/apk/repositories && \
    echo "http://dl-cdn.alpinelinux.org/alpine/edge/community/" >> /etc/apk/repositories && \
    echo "http://dl-cdn.alpinelinux.org/alpine/edge/main/" >> /etc/apk/repositories && \
    apk add --no-cache bash deluge
ADD pia-port.sh /scripts/pia-port.sh
RUN chmod +x /scripts/*.sh
CMD ["/scripts/pia-port.sh"]

pia-port.sh

#!/bin/bash

trap 'exit 0' SIGTERM

OLDPORT=0
PORT=0

while true
do
  [ -r "/pia-shared/port.dat" ] && PORT=$(cat /pia-shared/port.dat)

  if [ $OLDPORT -ne $PORT ]; then
    echo "Setting Deluge port settings ($PORT)..."
    deluge-console --config=/deluge/conf "config --set listen_ports ($PORT,$PORT)"
    OLDPORT=$PORT
  fi
  sleep 30 &
  wait $!
done

Some recent change in Alpine started causing these errors coming from the deluge binary:

Error relocating /usr/lib/libpython3.12.so.1.0: pwritev2: symbol not found
Error relocating /usr/lib/libpython3.12.so.1.0: preadv2: symbol not found

The solution is to upgrade the musl package when building the container, so your Dockerfile would then look like:

FROM alpine:latest
RUN echo "http://dl-cdn.alpinelinux.org/alpine/edge/testing/" >> /etc/apk/repositories && \
    echo "http://dl-cdn.alpinelinux.org/alpine/edge/community/" >> /etc/apk/repositories && \
    echo "http://dl-cdn.alpinelinux.org/alpine/edge/main/" >> /etc/apk/repositories && \
    apk add --no-cache bash deluge && \
    apk upgrade musl
ADD pia-port.sh /scripts/pia-port.sh
RUN chmod +x /scripts/*.sh
CMD ["/scripts/pia-port.sh"]