Ansible: transferring files between hosts - ansible

Question

With ansible, I'm trying to copy an application artifact from a remote server "artifacts_host" to a target machine, i.e. a host in my inventory. The play I'm trying to run is something like:
- name: rsync WAR artifact from artifacts host
synchronize: >
src={{ artifacts_path }}/{{ artifact_filename }}.war
dest={{ artifact_installation_dir }}
delegate_to: "{{ artifacts_host }}"
I came very close to getting this to work by using ansible-vault to encrypt a "secrets.yml" variable file with the artifact_host's public key and then installed it on the target machine's auth file like:
- name: install artifacts_host's public key to auth file
authorized_key: >
user={{ ansible_ssh_user }}
key='{{ artifacts_host_public_key }}'
sudo: yes
but the problem is that my artifacts_host cannot resolve an IP address from the FQDN that Ansible passes to it. If I was able to "inform" the artifacts_host of the IP to use (what the fqdn should resolve to) then I would be fine. I would also be fine having the task fire off on the target machine to pull from the artifacts_host, but I can't find an idempotent way of accomplishing this, nor can I figure out how to feed the target machine a login/password OR ssh key to use.
Am I just gonna have to template out a script to push to my targets???

Answer 1

For anyone who comes across this and has the same question, I did not really figure it out, I just decided to install the private key in the target machines' /etc/ssh directory and chmod it to 0600. I figure it's basically as secure as it could get without a transient (in-memory only) key/password and with idempotence.