Setting up n8n automation with Docker behind Traefik

This time, I want to create workflows for automation. This is possible, for example, with n8n.

n8n is an extendable workflow automation tool which enables you to connect anything to everything via its open, fair-code model.

To do this, we need a server with Docker and, in this case, Traefik as a reverse proxy, as described here. The setup is done in a few steps.

Installation n8n

We connect to the server and expand the environment configuration.

cd ~/docker
echo "N8N_POSTGRES_PASSWORD=$(openssl rand -hex 16)" >> .env
echo "N8N_USER=username" >> .env
echo "N8N_PASSWORD=securepassword" >> .env

Now we need new folders in which the data will be stored.

mkdir appdata/n8n
mkdir appdata/n8n/data
mkdir appdata/n8n/db

And a new docker-compose file.

cd ~/docker
nano docker-compose-n8n.yml

version: "3.7"

### NETWORKS ###
networks:
    web:
        external:
            name: web
    n8n-internal:
        external: false
    default:
        driver: bridge

### SERVICEs ###
services:
    n8n:
        container_name: n8n
        image: n8nio/n8n
        restart: unless-stopped
        networks:
            - n8n-internal
            - web
        security_opt:
            - no-new-privileges:true
        environment:
            - DB_TYPE=postgresdb
            - DB_POSTGRESDB_DATABASE=n8n
            - DB_POSTGRESDB_HOST=n8n-db
            - DB_POSTGRESDB_PORT=5432
            - DB_POSTGRESDB_USER=n8n
            - DB_POSTGRESDB_PASSWORD=${N8N_POSTGRES_PASSWORD}
            - N8N_BASIC_AUTH_ACTIVE=true
            - N8N_BASIC_AUTH_USER=${N8N_USER}
            - N8N_BASIC_AUTH_PASSWORD=${N8N_PASSWORD}
            - N8N_HOST=n8n.${DOMAINNAME}
            - WEBHOOK_TUNNEL_URL=https://n8n.${DOMAINNAME}
            - GENERIC_TIMEZONE=${TZ}
            - TZ=${TZ}
        volumes:
            - $DOCKERDIR/appdata/n8n/data:/home/node/
        labels:
            - "traefik.enable=true"
            - "traefik.http.routers.n8n-rtr.entrypoints=https"
            - "traefik.http.routers.n8n-rtr.rule=Host(`n8n.$DOMAINNAME`)"
            - "traefik.http.routers.n8n-rtr.tls=true"
            - "traefik.http.routers.n8n-rtr.service=n8n-svc"
            - "traefik.http.services.n8n-svc.loadbalancer.server.port=5678"
            - "traefik.http.routers.n8n-rtr.middlewares=chain-oauth@file"
        depends_on:
            - n8n-db

    n8n-db:
        container_name: n8n-db
        image: postgres
        restart: unless-stopped
        networks:
            - n8n-internal
        security_opt:
            - no-new-privileges:true
        environment:
            - POSTGRES_USER=n8n
            - POSTGRES_PASSWORD=${N8N_POSTGRES_PASSWORD}
            - POSTGRES_DB=n8n
            - POSTGRES_NON_ROOT_USER=n8n
            - POSTGRES_NON_ROOT_PASSWORD=${N8N_POSTGRES_PASSWORD}
        volumes:
            - $DOCKERDIR/appdata/n8n/db/:/var/lib/postgresql/data
        labels:
            - "traefik.enable=false"

When the page n8n.yourdomain.de is called up, a query asks for the username and password in the .env file.

Workflows can now be created.

Example workflow

Now, I would like to create an example workflow. This should send a daily email at the end with the percentage of disk space used in per cent. I add a new “Execute Command” node to the start field.

As a command, I add df -k / | tail -1 | awk '{print $5}' and press “Execute Node”.

I see that 4% of the disk space is occupied.

Next, I add a new “Send Email” node. The SMTP data must be entered here.

For the text, I click on the cogwheel next to the text field and select “Add Expression”.

The server's memory space is occupied by {{$json["stdout"]}}.

You can also test whether a mail is sent via “Execute Node”.

Successful workflow](@assets/images/blog/n8n-mit-traefik/images/success.png)

So that you don’t always have to run the workflow manually, I add a cron trigger. You can set how often everything should be executed.

I connect this trigger to the node and press play.

Now, I just have to save the workflow at the top right and set it to active.

I should get an email every week with the used disk space.