Docker Application launcher

Contents

• Docker Application launcher

  • Requirements

  • Networking

  • Volumes

  • Applications

  • Deployment example

    • deploy.yml

    • docker-compose.yml

    • nginx.conf

  • Setup

  • EAPI methods

    • app.get_config

Docker application launcher service allows to launch Docker containers (using docker compose) directly from EVA ICS.

The service is useful to keep the whole setup and deployment unified.

Requirements

Install Docker Engine and Docker compose plugin. In case if Docker engine is installed from the OS repository, make sure the compose plugin is present (or docker-compose binary for compose V1, deprecated).

Networking

If a private network is required, create it system-wide with a command:

docker network create eva --subnet 10.20.0.0/16

refer to Docker networking documentation for more info.

Volumes

Persistent volumes can be kept at any location of the local file systems.

Applications

By default Docker applications are uploaded into /opt/eva4/runtime/dapp folder (create if missing).

An application should contain docker-compose.yml file and optional configuration if required.

It is recommended to test applications with docker compose up command before deploying.

Application log messages are automatically fetched into EVA ICS logging subsystem on behalf of the launcher service instance.

Deployment example

The following EVA ICS deployment file deploys an official NGINX container which is used as a front-end/ingress for EVA ICS HMI.

deploy.yml

version: 4
content:
  - node: .local
    upload:
    - src: ./ingress.tgz
      target: dapp/ingress/
      extract: true
    svcs:
    - id: dapp.ingress
      params:
        bus:
          path: var/bus.ipc
        command: svc/eva-dapp
        config:
          path: ingress

The source files must be either compressed into a single archive or uploaded one-by-one.

docker-compose.yml

services:
  web:
    image: nginx
    networks:
      - eva
    volumes:
      - source: ./nginx.conf
        target: /etc/nginx/nginx.conf
        type: bind
    ports:
     - "80:80"
networks:
  eva:
    external: true

nginx.conf

Make sure the HMI service upstream is accessible from the Docker network the container is attached to. See also Front-end server for HMI service.

user  nginx;
worker_processes  4;
error_log  /dev/fd/1 warn;
pid        /var/run/nginx.pid;
events {
    worker_connections  1024;
}
http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;
    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';
    access_log  /dev/fd/0  main;
    sendfile        on;
    keepalive_timeout  65;
    gzip  on;
    upstream eva-hmi-default {
            server 10.20.0.1:7727;
    }
    server {
        listen 0.0.0.0;
        client_max_body_size 1M;
        server_name  eva;
        location / {
            proxy_buffers 16 16k;
            proxy_buffer_size 16k;
            proxy_busy_buffers_size 240k;
            proxy_pass http://eva-hmi-default;
            proxy_set_header X-Host $host;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-Proto https;
            proxy_set_header X-Frontend "nginx";
        }
        location /ws {
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
            proxy_buffers 16 16k;
            proxy_buffer_size 16k;
            proxy_busy_buffers_size 240k;
            proxy_pass http://eva-hmi-default;
            proxy_set_header X-Host $host;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-Proto https;
            proxy_set_header X-Frontend "nginx";
        }
    }
}

Setup

Use the template EVA_DIR/share/svc-tpl/svc-tpl-dapp.yml:

# Docker app service
command: svc/eva-dapp
bus:
  path: var/bus.ipc
config:
  # absolute path or relative to EVA_DIR/runtime/dapp
  path: app1
  # docker-compose version (1 or 2, default is 2)
  #compose_version: 2

Create the service using eva-shell:

eva svc create dapp.NAME /opt/eva4/share/svc-tpl/svc-tpl-dapp.yml

or using the bus CLI client:

cd /opt/eva4
cat DEPLOY.yml | ./bin/yml2mp | \
    ./sbin/bus ./var/bus.ipc rpc call eva.core svc.deploy -

(see eva.core::svc.deploy for more info)

EAPI methods

See EAPI commons for the common information about the bus, types, errors and RPC calls.

app.get_config

Description	Get app config (docker-compose.yml)
Parameters	none
Returns	Compose payload