https://arnoldbechtoldt.com/blog/saltstack-event-driven-infrastructure-with-salt-reactor

01-configure-master-and-minion.sh

# cat << EOF > /etc/salt/master
autosign_file: /etc/salt/autosign.conf
file_roots:
  base:
  - /srv/salt/states
reactor:
  - salt/minion/*/start:
    - /srv/salt/reactor/basic.sls
  - salt/job/*/ret/*:
    - /srv/salt/reactor/job_ret.sls
  - frontend/loadbalancer/pool/update:
    - /srv/salt/reactor/lb_pool_update.sls
EOF

# cat << EOF > /etc/salt/minion
master: 10.10.13.100
log_level: debug
EOF

02-deploy-autosign-file.sh

# echo '*.saltbox.local.inovex.de' > /etc/salt/autosign.conf

03-deploy-reactor-files.sh

# mkdir -p /srv/salt/{states,reactor}
# cat << EOF > /srv/salt/reactor/basic.sls
log_new_minion:
  local.cmd.run:
    - name: log new minion
    - tgt: 'master*'
    - arg:
      - 'echo "[{{ data['id'] }}][minion started] A new Minion has (re)born on $(date). Say hello to him ({{ tag }})" >> /tmp/salt.reactor.log'

tell_minion_to_install_software:
  local.state.sls:
    - name: tell minion to install software
    - tgt: {{ data['id'] }}
    - arg:
      - webserver
EOF

# cat << EOF > /srv/salt/reactor/job_ret.sls
{% if data['id'] != salt['grains.get']('fqdn') or data['fun'] != 'cmd.run' %}
log_minion_new_job:
  local.cmd.run:
    - name: log minion job
    - tgt: 'master*'
    - arg:
      - 'echo "[{{ data['id'] }}][ret job       ] A minion just executed {{ data['fun'] }}. ({{ tag }})" >> /tmp/salt.reactor.log'
{% endif %}
EOF

# cat << EOF > /srv/salt/reactor/lb_pool_update.sls
new_httpd_frontend_added_to_pool:
  local.cmd.run:
    - name: new httpd frontend added to pool
    - tgt: 'master*'
    - arg:
      - 'echo "[{{ data['id'] }}][new httpd     ] Adding new webserver ({{ data['data']['new_web_server_ip'] }}:80) to loadbalancer ({{ tag }})" >> /tmp/salt.reactor.log'
EOF

04-deploy-state-files.sh

# cat << EOF > /srv/salt/states/webserver.sls
#!jinja|yaml

httpd:
  pkg:
    - installed
  file:
    - managed
    - name: /etc/httpd/conf/httpd.conf
    - user: root
    - group: root
    - mode: 644
  service:
    - running
    - watch:
      - file: httpd

httpd_pool_update:
  event:
    - wait
    - name: frontend/loadbalancer/pool/update
    - data:
        new_web_server_ip: {{ salt['grains.get']('ip4_interfaces')['enp0s8'][0] }}
    - watch:
      - service: httpd
EOF

05-salt.reactor.log

[minion1.saltbox.local.inovex.de][minion started] A new Minion has (re)born on Sat Sep 19 19:19:13 CEST 2015. Say hello to him (salt/minion/minion1.saltbox.local.inovex.de/start)
[minion1.saltbox.local.inovex.de][ret job       ] A minion just executed mine.update. (salt/job/20150919191915617342/ret/minion1.saltbox.local.inovex.de)
[minion1.saltbox.local.inovex.de][new httpd     ] Adding new webserver (10.10.13.101:80) to loadbalancer (frontend/loadbalancer/pool/update)
[minion1.saltbox.local.inovex.de][ret job       ] A minion just executed state.sls. (salt/job/20150919191913799905/ret/minion1.saltbox.local.inovex.de)
[minion1.saltbox.local.inovex.de][minion started] A new Minion has (re)born on Sat Sep 19 19:20:20 CEST 2015. Say hello to him (salt/minion/minion1.saltbox.local.inovex.de/start)
[minion1.saltbox.local.inovex.de][minion started] A new Minion has (re)born on Sat Sep 19 19:30:30 CEST 2015. Say hello to him (salt/minion/minion1.saltbox.local.inovex.de/start)