A script to auto update your nginx proxy for your docker containers

update-nginx

#!/bin/sh

MAPPING_FILE=$1
CONTAINERS=($(docker ps | awk 'NR>1' | perl -ne '@cols = split /\s{2,}/, $_; printf "%30s %20s %20s\n", $cols[6], $cols[0]' | awk '{print $1":"$2}'))
readarray DOMAINS < $MAPPING_FILE
NGINX_CONF_FILE=/etc/nginx/sites-enabled/auto-update

function getIPByName {
    local NAME=$1
    
    docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' $NAME
}

function getNginxConf {
    local DOMAIN=$1
    local IP=$2
    local PORT_HOST=$3
    local PORT_CONTAINER=$4
    local IP_HOST=$5
    local IP_PORT=""

    if [ -n "$IP_HOST" ]; then
        IP_PORT="$IP_HOST:$PORT_HOST"
    else
        IP_PORT="$PORT_HOST"
    fi

cat <<EOF
server {
    listen $IP_PORT;
    server_name $DOMAIN;

    location / {
        proxy_pass http://$IP:$PORT_CONTAINER;
        proxy_set_header  Host               \$host;
        proxy_set_header  X-Forwarded-Server \$host;
        proxy_set_header  X-Real-IP          \$remote_addr;
        proxy_set_header  X-Forwarded-For    \$proxy_add_x_forwarded_for;
        proxy_set_header  X-Forwarded-Proto  \$scheme;
    }
}
EOF
}

function eraseAutoUpdateConf {
    rm -rf $NGINX_CONF_FILE
}

/etc/init.d/nginx stop

eraseAutoUpdateConf

for mapping in "${DOMAINS[@]}"
do
    NAME=$(echo $mapping | awk -F ':' '{print $1}')
    DOMAIN=$(echo $mapping | awk -F ':' '{print $2}')
    PORT_HOST=$(echo $mapping | awk -F ':' '{print $3}')
    PORT_CONTAINER=$(echo $mapping | awk -F ':' '{print $4}')
    IP_HOST=$(echo $mapping | awk -F ':' '{print $5}')
    IP=$(getIPByName $NAME)
    CONF=$(getNginxConf $DOMAIN $IP $PORT_HOST $PORT_CONTAINER $IP_HOST)

    echo $CONF >> $NGINX_CONF_FILE
done

/etc/init.d/nginx start

eg : Given you have a mapping file :

/home/user/mapping-nginx :

laboard:laboard.domain.tld:80:80:1.2.3.4
gitlab:gitlab.domain.tld:80:80:2.3.4.5
gitlab-ci:gitlab-ci.domain.tld:80:80:1.2.3.4

Retrieve the script :

cd /home/user wget -O update-nginx.sh https://gist.githubusercontent.com/CaporalDead/c5389e0159c7818d3aa6/raw/b4b1f337161f006f1f2db1eff439ebcb9019938b/update-nginx chmod +x update-nginx.sh

Execute :

./update-nginx.sh /home/user/mapping-nginx

You can also put the script in /usr/bin. You need to have privileges to execute this script, it depends on your configuration (using sudo, etc...)