Add community prometheus cookbook

cookbooks/prometheus/templates/default/prometheus.yml.erb

@@ -0,0 +1,33 @@
+# Global default settings.
+global:
+  <% @global_config.each do |k,v| %>
+  <%=k%>: "<%=v%>"
+  <% end %>
+
+scrape_configs:
+<% @jobs.each do |name, job| %>
+- job_name: "<%= name %>"
+  <% if job['scrape_interval'] %>
+  scrape_interval: "<%= job['scrape_interval'] %>"
+  <% end %>
+  <% if job['scrape_timeout'] %>
+  scrape_timeout: "<%= job['scrape_timeout'] %>"
+  <% end %>
+  metrics_path: "<%= job['metrics_path'] %>"
+  static_configs:
+    - targets: <%=  Array(job['target']) %>
+    <%if job['labels'] %>
+      labels:
+      <% job['labels'].each do |label,label_config| %>
+        <%=label%>: <%=label_config%>
+      <%end%>
+    <%end%>
+
+  <% end %>
+
+<% if @rule_filenames %>
+rule_files:
+<% @rule_filenames.each do |filename| %>
+  - <%= filename %>
+<% end %>
+<% end %>