start.sh

#!/bin/bash

function log() {
   if [[ $# == 1 ]]; then
      level="info"
      msg=$1
   elif [[ $# == 2 ]]; then
      level=$1
      msg=$2
   fi
   echo "$(date -u +"%Y-%m-%dT%H:%M:%SZ") [controller] [${level}] ${msg}"
}

if ((TOR_INSTANCES < 1)); then
   log "fatal" "Environment variable TOR_INSTANCES has to be bigger than 1..."
   exit 1
fi

if ((TOR_REBUILD_INTERVAL < 600)); then
   log "fatal" "Environment variable TOR_REBUILD_INTERVAL has to be bigger than 600 seconds"
   # otherwise AWS may complain about it, because http://checkip.amazonaws.com is asked too often
   exit 2
fi

base_tor_socks_port=10000
base_tor_ctrl_port=20000
base_http_port=30000

log "Start creating a pool of ${TOR_INSTANCES} tor instances..."

# "reset" the HAProxy config file because it may contain the previous Privoxy instances information from the previous docker run
cp /etc/haproxy/haproxy.cfg.default /etc/haproxy/haproxy.cfg

for ((i = 0; i < TOR_INSTANCES; i++)); do
   #
   # start one tor instance
   #
   socks_port=$((base_tor_socks_port + i))
   ctrl_port=$((base_tor_ctrl_port + i))
   tor_data_dir="/var/local/tor/${i}"
   mkdir -p "${tor_data_dir}" && chmod -R 700 "${tor_data_dir}" && chown -R tor: "${tor_data_dir}"
   # spawn a child process to run the tor server at foreground so that logging to stdout is possible
   (tor --PidFile "${tor_data_dir}/tor.pid" \
      --SocksPort 127.0.0.1:"${socks_port}" \
      --ControlPort 127.0.0.1:"${ctrl_port}" \
      --dataDirectory "${tor_data_dir}" 2>&1 |
      sed -r "s/^(\w+\ [0-9 :\.]+)(\[.*)[\r\n]?$/$(date -u +"%Y-%m-%dT%H:%M:%SZ") [tor#${i}] \2/") &
   #
   # start one privoxy instance connecting to the tor socks
   #
   http_port=$((base_http_port + i))
   privoxy_data_dir="/var/local/privoxy/${i}"
   mkdir -p "${privoxy_data_dir}" && chown -R privoxy: "${privoxy_data_dir}"
   cp /etc/privoxy/config.templ "${privoxy_data_dir}/config"
   sed -i \
      -e 's@PLACEHOLDER_CONFDIR@'"${privoxy_data_dir}"'@g' \
      -e 's@PLACEHOLDER_HTTP_PORT@'"${http_port}"'@g' \
      -e 's@PLACEHOLDER_SOCKS_PORT@'"${socks_port}"'@g' \
      "${privoxy_data_dir}/config"
   # spawn a child process
   (privoxy \
      --no-daemon \
      --user privoxy \
      --pidfile "${privoxy_data_dir}/privoxy.pid" \
      "${privoxy_data_dir}/config" 2>&1 |
      sed -r "s/^([0-9\-]+\ [0-9:\.]+\ [0-9a-f]+\ )([^:]+):\ (.*)[\r\n]?$/$(date -u +"%Y-%m-%dT%H:%M:%SZ") [privoxy#${i}] [\L\2] \E\3/") &
   #
   # "register" the privoxy instance to haproxy
   #
   echo "  server privoxy${i} 127.0.0.1:${http_port} check" >>/etc/haproxy/haproxy.cfg
done
#
# start an HAProxy instance
#
(haproxy -db -- /etc/haproxy/haproxy.cfg 2>&1 |
   sed -r "s/^(\[[^]]+]\ )?([\ 0-9\/\():]+)?(.*)[\r\n]?$/$(date -u +"%Y-%m-%dT%H:%M:%SZ") [haproxy] \L\1\E\3/") &
# seems like haproxy starts logging only when the first request processed. We wait 15 seconds to build the first circuit then issue a
# request to "activate" the HAProxy
log "Wait 15 seconds to build the first Tor circuit"
sleep 15
curl -sx "http://127.0.0.1:3128" https://google.com >/dev/null
#
# endless loop to reset circuits
#
while :; do
   log "Wait ${TOR_REBUILD_INTERVAL} seconds to rebuild all the tor circuits"
   sleep "$((TOR_REBUILD_INTERVAL))"
   log "Rebuilding all the tor circuits..."
   for ((i = 0; i < TOR_INSTANCES; i++)); do
      http_port=$((base_http_port + i))
      IP=$(curl -sx "http://127.0.0.1:${http_port}" http://checkip.amazonaws.com)
      log "Current external IP address of proxy #${i}/${TOR_INSTANCES}: ${IP}"
   done
done