#95 enable basic prometheus installation on demand

Vagrantfile

@@ -17,6 +17,7 @@ Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
   config.vm.network :forwarded_port, guest: 8080, host: 8080, auto_correct: true # Glassfish API Endpoint
   config.vm.network :forwarded_port, guest: 8181, host: 8181, auto_correct: true # ???
   config.vm.network :forwarded_port, guest: 8983, host: 8983, auto_correct: true # Solr
+  config.vm.network :forwarded_port, guest: 9090, host: 9090, auto_correct: true # Prometheus
 
   config.vm.provision :ansible_local do |ansible|
     ansible.playbook = "tests/site.yml"

defaults/main.yml

@@ -117,6 +117,13 @@ munin:
     user: admin
     passwd: p4sswurd
 
+prometheus:
+  install: false
+  node_exporter: https://github.com/prometheus/node_exporter/releases/download/v0.18.1/node_exporter-0.18.1.linux-amd64.tar.gz
+  root: /usr/local/prometheus
+  url: https://github.com/prometheus/prometheus/releases/download/v2.11.1/prometheus-2.11.1.linux-amd64.tar.gz
+  user: prometheus
+
 rserve:
   install: true
   host: localhost

files/prometheus.yml

@@ -0,0 +1,22 @@
+global:
+  scrape_interval:	30s
+  evaluation_interval:	30s
+  scrape_timeout:	30s
+
+# Alertmanager configuration
+alerting:
+  alertmanagers:
+  - static_configs:
+    - targets:
+      # - alertmanager:9093
+
+# Load rules once and periodically evaluate them according to the global 'evaluation_interval'.
+rule_files:
+
+  - prometheus-cpu.yml
+
+scrape_configs:
+
+  - job_name: 'dataverse'
+    static_configs:
+    - targets: ['localhost:9090']

tasks/main.yml

@@ -70,5 +70,9 @@
   when: munin.install == true
   tags: munin
 
+- include: prometheus.yml
+  when: prometheus.install == true
+  tags: prometheus
+
 - name: Fin
   debug: msg="Dataverse installation complete! Please check output logs in /tmp for further review."

tasks/prometheus.yml

@@ -0,0 +1,86 @@
+---
+
+- name: add prometheus service account
+  user:
+    name: '{{ prometheus.user }}'
+
+# firewalld is outside the role scope
+#- name: punch prometheus firewall holes
+#  firewalld:
+#    port: '{{ item }}'
+#    permanent: yes
+#    state: enabled
+#  with_items:
+#  - 9090/tcp
+#  - 9100/tcp
+
+- name: unarchive won't create directory
+  file:
+    path: '{{ prometheus.root }}'
+    state: directory
+    owner: '{{ prometheus.user }}'
+    mode: '0755'
+
+- name: install prometheus
+  unarchive:
+    src: '{{ prometheus.url }}'
+    dest: '{{ prometheus.root }}'
+    owner: '{{ prometheus.user }}'
+    remote_src: yes
+    extra_opts: [--strip-components=1]
+
+- name: copy prometheus config file
+  copy:
+    src: prometheus.yml
+    dest: '{{ prometheus.root }}/prometheus.yml'
+    owner: '{{ prometheus.user }}'
+    mode: 0644
+
+- name: node_exporter dir must exist
+  file:
+    path: '{{ prometheus.root }}/node_exporter'
+    state: directory
+    owner: '{{ prometheus.user }}'
+    mode: '0755'
+
+- name: install node_exporter
+  unarchive:
+    src: '{{ prometheus.node_exporter }}'
+    dest: '{{ prometheus.root }}/node_exporter'
+    remote_src: yes
+    extra_opts: [--strip-components=1]
+
+- name: place prometheus systemd template
+  template:
+    src: prometheus.service.j2
+    dest: /usr/lib/systemd/system/prometheus.service
+    owner: root
+    group: root
+    mode: 0644
+
+- name: place node_exporter systemd template
+  template:
+    src: node_exporter.service.j2
+    dest: /usr/lib/systemd/system/node_exporter.service
+    owner: root
+    group: root
+    mode: 0644
+
+- name: reload systemd
+  shell: systemctl daemon-reload
+
+- name: start and enable prometheus
+  systemd:
+    name: prometheus
+    state: started
+    enabled: yes
+
+- name: give prometheus a breather
+  pause:
+    seconds: 2
+
+- name: start and enable node_exporter
+  systemd:
+    name: prometheus
+    state: started
+    enabled: yes

templates/node_exporter.service.j2

@@ -0,0 +1,11 @@
+[Unit]
+Description=Node Exporter
+Wants=network-online.target
+After=network-online.target
+
+[Service]
+User=prometheus
+ExecStart={{ prometheus.root }}/node_exporter/node_exporter
+
+[Install]
+WantedBy=default.target

templates/prometheus.service.j2

@@ -0,0 +1,17 @@
+[Unit]
+Description=Prometheus Server
+Documentation=https://prometheus.io/docs/introduction/overview/
+After=network-online.target
+
+[Service]
+User=prometheus
+Restart=on-failure
+
+#Change this line if you download the 
+#Prometheus on different path user
+ExecStart={{ prometheus.root }}/prometheus \
+  --config.file={{ prometheus.root }}/prometheus.yml \
+  --storage.tsdb.path={{ prometheus.root }}/data
+
+[Install]
+WantedBy=multi-user.target

tests/group_vars/vagrant.yml

@@ -112,11 +112,18 @@ dataverse:
     enabled: true
 
 munin:
-  install: true
+  install: false
   admin:
     user: admin
     passwd: p4sswurd
 
+prometheus:
+  install: true
+  node_exporter: https://github.com/prometheus/node_exporter/releases/download/v0.18.1/node_exporter-0.18.1.linux-amd64.tar.gz
+  root: /usr/local/prometheus
+  url: https://github.com/prometheus/prometheus/releases/download/v2.11.1/prometheus-2.11.1.linux-amd64.tar.gz
+  user: prometheus
+
 rserve:
   install: true
   host: localhost