Install docker and start service

sudo pacman -S docker docker-compose
sudo systemctl enable docker.service
sudo systemctl start docker.service

#Verify
docker info

Permission error

If using jenkins

The user jenkins needs to be added to the group docker:

sudo usermod -a -G docker jenkins

Then restart Jenkins.

Otherwise

If you arrive to this question of stack overflow because you receive this message from docker, but you don't use jenkins, most probably the error is the same: your unprivileged user does not belong to the docker group.

You can do:

sudo usermod -a -G docker $USER

You can check it was successful by doing grep docker /etc/group and see something like this:

docker:x:998:[user]

in one of the lines.

Then change your users group ID to docker (to avoid having to log out and log in again):

newgrp docker

Running database container

[[Tech Help/Docker/PG Container|PG Container]]

ModelMapper modelMapper = new ModelMapper();  

// Key line along with the cascade thing to make nested objects work while saving from API  
// to DB. Man idk what exactly all this does it feels like random syntax for now.  
// Where to we even learn what syntax to use for our what we want to achieve.  
modelMapper.getConfiguration().setMatchingStrategy(MatchingStrategies.LOOSE);  
return modelMapper;

Running a Postgres container

Commands to spin up PG container which can be connected to from anywhere using VM IP and port.

docker run --name postgres_1 -p 5432:5432 -e POSTGRES_PASSWORD=postgres -d postgres

To resolve the network iptables error

sudo iptables -t filter -F
sudo iptables -t filter -X
sudo systemctl restart docker

To connect to bash of container

docker ps
docker exec -it <container-id> bash

docker run --name postgres_2 -v $(pwd)/datadir:/var/lib/pg_data -p 5433:5432 -e POSTGRES_PASSWORD=postgres -d postgres

https://blog.nextideatech.com/how-to-create-a-django-app-and-connect-it-to-a-database/