launch-workers.yml

- hosts: localhost
  connection: local
  gather_facts: False
  vars_files: 
    - vars.yml
  tasks:
    - name: create digital ocean workers
      digital_ocean_droplet:
        state: present
        name: "locust-{{ item.0 }}-{{ item.1 }}"
        private_networking: no
        size: "{{ locust_node_size }}"
        image_id: ubuntu-20-04-x64
        region: "{{ item.0 }}"
        ssh_keys: "{{ locust_ssh_keys }}"
        unique_name: yes
        tags:
          - locust
      loop: "{{ locust_regions|product(range(0,locust_nodes_per_region,1))|list }}"
      register: do
    - debug: var=do
    - name: tag droplets
      digital_ocean_tag:
        name: locust
        resource_id: "{{ item.data.droplet.id }}"
        state: present
      when: item.data is defined
      with_items: "{{ do.results }}"
    - name: add digital ocean workers to inventory
      add_host:
        name: "{{ item.data.ip_address }}"
        groups: do
        ansible_ssh_extra_args: '-o StrictHostKeyChecking=no'
        ansible_python_interpreter: /usr/bin/python3
      when: item.data is defined
      with_items: "{{ do.results }}"


- hosts: do
  remote_user: root
  gather_facts: False
  vars_files: 
    - vars.yml
  tasks:
    - name: Wait for hosts to become reachable
      wait_for_connection:

    - name: install ansible prereqs
      script: ansible_prereqs_3.sh creates=/root/.ansible_prereqs_installed
      register: ans_preq
      changed_when: "'CHANGE' in ans_preq.stdout"

    - name: Install pip
      apt:
        pkg: ['python3-pip']
        state: present

    - name: Install locust
      pip:
        name: locust
        state: present

    - name: Copy locust file
      copy: 
        src: locust.py
        dest: /root/locust.py
      register: locust_file
  
    - name: Copy service file
      template: 
        src: locust.service
        dest: /etc/systemd/system/locust.service
      register: service_template

    - name: Systemd restart
      systemd:
        daemon_reload: yes
        name: locust
        state: restarted
      when: locust_file is changed or service_template is changed

    - name: Ensure locust is running
      systemd:
        name: locust
        state: started
        enabled: yes