lb-reload

#! /bin/sh

SPLIT_TOKEN=${SPLIT_TOKEN:-__split__}

entries=$(cat /etc/lb/entries | grep . | sort | uniq)

# Compile backend data into entries.yml
domains=
frontends=
current_backend=
current_domain=
current_ip=
echo "backends:" > /etc/lb/entries.yml
for entry in $entries; do
  stack=$(echo $entry | awk -F "$SPLIT_TOKEN" '{ print $1 }')
  service=$(echo $entry | awk -F "$SPLIT_TOKEN" '{ print $2 }')
  port=$(echo $entry | awk -F "$SPLIT_TOKEN" '{ print $3 }')
  if [[ "${stack}_${service}_${port}" != "$current_backend" ]]; then
    echo "  -" >> /etc/lb/entries.yml
    echo "    id: ${stack}_${service}_${port}" >> /etc/lb/entries.yml
    echo "    stack: $stack" >> /etc/lb/entries.yml
    echo "    service: $service" >> /etc/lb/entries.yml
    echo "    port: $port" >> /etc/lb/entries.yml
    current_backend="${stack}_${service}_${port}"
    current_domain=
    current_ip=
  fi
  key=$(echo $entry | awk -F "$SPLIT_TOKEN" '{ print $4 }')
  value=$(echo $entry | awk -F "$SPLIT_TOKEN" '{ print $5 }')
  if [[ "$key" == "frontend" ]]; then
    frontends="$frontends $value"
    port=$(echo $value | awk -F '/' '{ print $1 }')
    mode=$(echo $value | awk -F '/' '{ print $2 }')
    case $port in
      ''|*[!0-9]*) is_number="false" ;;
      *) is_number="true" ;;
    esac
    echo "    frontend: $value" >> /etc/lb/entries.yml
    if [[ "$is_number" == 'true' && "$mode" != "" ]]; then
      echo "    mode: $mode" >> /etc/lb/entries.yml
    fi
  elif [[ "$key" == "domain" || "$key" == "domains" ]]; then
    if [[ "$current_domain" == "" ]]; then
      echo "    domains:" >> /etc/lb/entries.yml
    fi
    current_domain=$value
    for domain in $(echo $value | tr ',' ' '); do
      proto="$(echo $domain | grep :// | sed -e's,^\(.*://\).*,\1,g')"
      url="$(echo ${domain##$proto})"
      proto="$(echo ${proto%://})"
      auth="$(echo $url | grep @ | cut -d@ -f1)"
      user="$(echo "$auth" | awk -F ':' '{ print $1 }')"
      pass="$(echo "$auth" | awk -F ':' '{ print $2 }')"
      host="$(echo ${url##$auth@} | cut -d/ -f1)"
      port="$(echo $host | sed -e 's,^.*:,:,g' -e 's,.*:\([0-9]*\).*,\1,g' -e 's,[^0-9],,g')"
      path="$(echo $url | grep / | cut -d/ -f2-)"
      echo "      -" >> /etc/lb/entries.yml
      echo "        id: $(echo $domain | sed -E 's/[[:punct:]]/_/g')" >> /etc/lb/entries.yml
      if [[ "$proto" != "" ]];  then echo "        scheme: $proto" >> /etc/lb/entries.yml; fi
      if [[ "$user" != "" ]];   then echo "        user: $user" >> /etc/lb/entries.yml; fi
      if [[ "$pass" != "" ]];   then echo "        pass: $pass" >> /etc/lb/entries.yml; fi
      if [[ "$host" != "" ]];   then echo "        host: $host" >> /etc/lb/entries.yml; fi
      if [[ "$path" != "" ]];   then echo "        path: /$path" >> /etc/lb/entries.yml; fi

      domains="${current_backend} $(echo $domain | sed -E 's/[[:punct:]]/_/g') $(echo $host/$path | wc -c | tr -d ' ')
$domains"
    done
  elif [[ "$key" == "container" ]]; then
    ip=$value
    state=$(echo $entry | awk -F "$SPLIT_TOKEN" '{ print $6 }')
    health=$(echo $entry | awk -F "$SPLIT_TOKEN" '{ print $7 }')

    if [[ "$health" == "healthy" && "$state" == "running" ]]; then
      health="true"
    else
      health="false"
    fi

    if [[ "$current_ip" == "" ]]; then
      echo "    containers:" >> /etc/lb/entries.yml
    fi

    current_ip=$ip
    echo "      -" >> /etc/lb/entries.yml
    echo "        ip: $ip" >> /etc/lb/entries.yml
    echo "        healthy: $health" >> /etc/lb/entries.yml
  fi
done

if [[ "$domains" == "" ]]; then
  echo "_sorted: []" >> /etc/lb/entries.yml
else
  domains=$(echo "$domains" | sort -k3 -n -r)
  echo "_sorted:" >> /etc/lb/entries.yml
  IFS=$'\n'; for domain in $domains; do
    b=$(echo "$domain" | awk '{ print $1 }')
    d=$(echo "$domain" | awk '{ print $2 }')
    echo "  - " >> /etc/lb/entries.yml
    echo "    backend: '$b'" >> /etc/lb/entries.yml
    echo "    domain: '$d'" >> /etc/lb/entries.yml
  done
fi

frontends=$(echo "$frontends" | tr ' ' '\n' | sort | uniq)
echo "frontends:" >> /etc/lb/entries.yml
for frontend in $frontends; do
  port=$(echo $frontend | awk -F '/' '{ print $1 }')
  mode=$(echo $frontend | awk -F '/' '{ print $2 }')
  case $port in
    ''|*[!0-9]*) is_number="false" ;;
    *) is_number="true" ;;
  esac
  if [[ "$is_number" == 'true' ]]; then
    echo "  $frontend:" >> /etc/lb/entries.yml
    echo "    name: $(echo $frontend | sed -E 's/[[:punct:]]/_/g')" >> /etc/lb/entries.yml
    echo "    port: $port" >> /etc/lb/entries.yml
    echo "    mode: ${mode:-http}" >> /etc/lb/entries.yml
  fi
done

# Download service metadata to metadata.yml and parse root domains
curl -s -H 'Accept: application/json' http://rancher-metadata.rancher.internal/latest/self/service/metadata \
  | jq '.domains = (.domains | map(capture("(?<scheme>.*://)?(?<host>.*)")
    | { scheme: .scheme[0:-3],  host }
    | { scheme, host, id: (.scheme + "_" + .host | gsub("[.]"; "_")) }))' \
  | json2yml > /etc/lb/metadata.yml

# Merge entries and metadata to config.yml
node -e "m = require('merge-yaml'); console.log(JSON.stringify(m(['/etc/lb/entries.yml','/etc/lb/metadata.yml'])));" | json2yml > /etc/lb/config.yml

# Generate haproxy config file
gotpl /etc/lb/haproxy.cfg.tpl </etc/lb/config.yml > /etc/lb/haproxy.cfg

# Validate haproxy config and reload
if haproxy -c -f /etc/lb/haproxy.cfg; then
  cp /etc/lb/haproxy.cfg /etc/haproxy/haproxy.cfg
  /usr/local/sbin/haproxy -D -p /var/run/haproxy.pid -f /etc/haproxy/haproxy.cfg -sf $(cat /var/run/haproxy.pid)
else
  echo "invalid haproxy config"
fi