postgresql affinity - docker service to swarm

Question

I am new to docker, and I have a problem. I want to gain affinity and exchanging data between two nodes in docker swarm.

(example ip)

I have one as manager: 192.168.10.1

and worker on: 192.168.10.2

They are already connected.

I have wrote docker-compose.yml file to create new service with postgres DB, and manager yml file looks like:

version: '3.1'

services:
    db:
        image: postgres
        environment:
            POSTGRES_DB: My_DB
            POSTGRES_USER: My_DB_User
            POSTGRES_PASSWORD: My_DB_Password
            PG_DATA: /var/lib/postgresql/data/pgdatai
        deploy:
            placement:
                constraints:
                    - node.role == manager
                    - node.labels.type == queue

    adminer:
        image: adminer
        ports:
            - 8080:8080

and worker:

version: '3.1'

services:
    db:
        image: postgres
        environment:
            POSTGRES_DB: My_DB
            POSTGRES_USER: My_DB_User
            POSTGRES_PASSWORD: My_DB_Password
            PG_DATA: /var/lib/postgresql/data/pgdatai
        deploy:
            placement:
                constraints:
                    - node.role == worker
                    - node.labels.type == queue

    adminer:
        image: adminer
        ports:
            - 8080:8080

And I dont have any stack on my machines. Doing command below (not sure if correct one) I have an error: yaml: line 2: did not find expected key

docker stack deploy --compose-file docker-compose.yml my_hostname

my hostname is read by me from command docker node ls in manager machine

Maybe someone has dealed with a very similiar issue and goals and can give me a guidance. I have looked at several demos on internet, but I found those a little bit useless. I would appreciate any help and guides of how I can achieve this "backup"

Answer 1

Ok, so I now understand yaml more. For anyone else, who occures similar problems:

1) check your writing in yml file. You should take double care about white marks.

2) I reconfigured yml file:

version: '3'
services:
 db:
  image: postgres
  environment:
   POSTGRES_DB: db_db
   POSTGRES_USER: db_user
   POSTGRES_PASSWORD: db_pass
   PG_DATA: /var/lib/postgresql/data/pgdatai
  expose:
   - "5432"
  ports:
   - "5432:5432"
  volumes:
   - /var/lib/postresql/db/
  deploy:
   placement:
    constraints:
     - node.hostname == vmAPI1

3) I used command for putting service to running swarm:

docker stack deploy --compose-file docker-compose.yml name_of_your_manager_swarm