This image will auto-generate its own config file for a load-balancer.
It looks for environment variables in the following formats:
<service-name>_<service-instance-id>_PORT_80_TCP_ADDR=x.x.x.x
<service-name>_PATH=<some path>
Optional/Conditional environment variables:
<service-name>_REMOTE_PORT=<remoteport> (optional - default: 80)
<service-name>_REMOTE_PATH=<remotepath> (optional - default: /)
<service-name>_BALANCING_TYPE=[ip_hash|least_conn] (optional)
<service-name>_EXPOSE_PROTOCOL=[http|https|both] (optional - default: http)
<service-name>_HOSTNAME=<vhostname> (required if <service-name>_EXPOSE_PROTOCOL is https or both)
<service-name>_ACCESS_LOG=[/dev/stdout|off] (optional - default: /dev/stdout)
<service-name>_ERROR_LOG=[/dev/stdout|/dev/null] (optional - default: /dev/stdout)
<service-name>_LOG_LEVEL=[emerg|alert|crit|error|warn|notice|info|debug'] (optional - default: error)
<env-formatted-vhostname>_SSL_CERTIFICATE=<something.pem> (required if the vhost will need ssl support)
<env-formatted-vhostname>_SSL_CERTIFICATE_KEY=<something.key> (required if the vhost will need ssl support)
<env-formatted-vhostname>_SSL_DHPARAM=<dhparam.pem> (required if the vhost will need ssl support)
<env-formatted-vhostname>_SSL_CIPHERS=<"colon separated ciphers wrapped in quotes"> (required if the vhost will need ssl support)
<env-formatted-vhostname>_SSL_PROTOCOLS=<protocol (e.g. TLSv1.2)> (required if the vhost will need ssl support)
And will build an nginx config file.
Example:
# automatically created environment variables (docker links)
WEBAPP_1_PORT_80_TCP_ADDR=192.168.0.2
WEBAPP_2_PORT_80_TCP_ADDR=192.168.0.3
WEBAPP_3_PORT_80_TCP_ADDR=192.168.0.4
API_1_PORT_80_TCP_ADDR=192.168.0.5
API_2_PORT_80_TCP_ADDR=192.168.0.6
TOMCAT_1_PORT_8080_TCP_ADDR=192.168.0.7
TOMCAT_2_PORT_8080_TCP_ADDR=192.168.0.8
# special environment variables
WEBAPP_PATH=/
WEBAPP_BALANCING_TYPE=ip_hash
WEBAPP_EXPOSE_PROTOCOL=both
WEBAPP_HOSTNAME=www.example.com
WEBAPP_ACCESS_LOG=off
WEBAPP_ERROR_LOG=/dev/stdout
WEBAPP_LOG_LEVEL=emerg
API_PATH=/api/
API_EXPOSE_PROTOCOL=https
API_HOSTNAME=www.example.com
WWW_EXAMPLE_COM_SSL_CERTIFICATE=ssl/something.pem
WWW_EXAMPLE_COM_SSL_CERTIFICATE_KEY=ssl/something.key
WWW_EXAMPLE_COM_SSL_DHPARAM=ssl/dhparam.pem
WWW_EXAMPLE_COM_SSL_CIPHERS="ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256"
WWW_EXAMPLE_COM_SSL_PROTOCOLS=TLSv1.2
TOMCAT_PATH=/javaapp
TOMCAT_REMOTE_PORT=8080
TOMCAT_REMOTE_PATH=/javaapp
Generates (/etc/nginx/sites-enabled/proxy.conf):
upstream webapp {
ip_hash;
server 192.168.0.2;
server 192.168.0.3;
server 192.168.0.4;
}
upstream api {
server 192.168.0.5;
server 192.168.0.6;
}
upstream tomcat {
server 192.168.0.7;
server 192.168.0.8;
}
server {
listen 80;
listen [::]:80 ipv6only=on;
server_name www.example.com;
error_log /dev/stdout emerg;
access_log off;
root /usr/share/nginx/html;
location / {
proxy_pass http://webapp:80/;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_http_version 1.1;
proxy_set_header Connection "";
proxy_buffering off;
}
}
server {
listen 443;
server_name www.example.com;
root html;
index index.html index.htm;
ssl on;
ssl_certificate ssl/something.pem;
ssl_certificate_key ssl/something.key;
# Diffie-Hellman parameter for DHE ciphersuites, recommended 2048 bits
ssl_dhparam ssl/dhparam.pem;
ssl_session_timeout 5m;
ssl_protocols TLSv1.2;
ssl_ciphers "ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256";
ssl_prefer_server_ciphers on;
root /usr/share/nginx/html;
location / {
proxy_pass http://webapp:80/;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_http_version 1.1;
proxy_set_header Connection "";
proxy_buffering off;
}
location /api/ {
proxy_pass http://api:80/;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_http_version 1.1;
proxy_set_header Connection "";
proxy_buffering off;
}
}
server {
listen 80;
listen [::]:80 ipv6only=on;
root /usr/share/nginx/html;
location /javaapp {
proxy_pass http://tomcat:8080/javaapp;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_http_version 1.1;
proxy_set_header Connection "";
proxy_buffering off;
}
}