add Centos Support

tasks/centos.yml

+---
+- name: create the node_exporter account
+  user:
+    create_home: false
+    name: node_exporter
+    shell: "/bin/false"
+
+
+- name: Download node_exporter
+  get_url:
+    url: https://copr.fedorainfracloud.org/coprs/ibotty/prometheus-exporters/repo/epel-7/ibotty-prometheus-exporters-epel-7.repo
+    dest: /etc/yum.repos.d/_copr_ibotty-prometheus-exporters.repo
+
+- name: Install the 'node_exporter'
+  yum:
+    name: "node_exporter"
+    state: present
+
+- name: deploy the service definition file
+  template:
+    dest: /etc/systemd/system/node_exporter.service
+    src: node_exporter_centos.service
+
+- name: deploy additional service options config file
+  template:
+    dest: /etc/nodeexport.conf
+    src: nodeexport.conf
+
+- name: reload systemd to take the new service into account
+  systemd:
+    daemon_reload: yes
+    enabled: yes
+    name: node_exporter
+    state: started

tasks/debian.yml

+---
+- name: create the node_exporter account
+  user:
+    create_home: false
+    name: node_exporter
+    shell: "/bin/false"
+
+- name: unpack node_exporter
+  unarchive:
+    remote_src: yes
+    src: https://github.com/prometheus/node_exporter/releases/download/v0.18.1/node_exporter-0.18.1.linux-amd64.tar.gz
+    dest: /tmp
+
+- name: move the node_exporter to the final destination
+  copy:
+    dest: /usr/local/bin/node_exporter
+    src: /tmp/node_exporter-0.18.1.linux-amd64/node_exporter
+    owner: node_exporter
+    group: node_exporter
+    mode: "u+x"
+    remote_src: yes
+
+- name: deploy the service definition file
+  template:
+    dest: /etc/systemd/system/node_exporter.service
+    src: node_exporter.service
+
+- name: deploy additional service options config file
+  template:
+    dest: /etc/nodeexport.conf
+    src: nodeexport.conf
+
+- name: reload systemd to take the new service into account
+  systemd:
+    daemon_reload: yes
+    enabled: yes
+    name: node_exporter
+    state: started

templates/node_exporter_centos.service

+[Unit]
+Description=Node Exporter
+Wants=network-online.target
+After=network-online.target
+
+[Service]
+User=node_exporter
+Group=node_exporter
+Type=simple
+EnvironmentFile=/etc/nodeexport.conf
+ExecStart=/usr/sbin/node_exporter $ARG1 $ARG2 $ARG3 $ARG5 $ARG6 $ARG7
+
+[Install]
+WantedBy=multi-user.target