Remove metrics-elb-full in favor of metrics-elb + fix --scheme and --…

…fetch_age

Both were doing mostly the same, in slightly different ways.

Once fixed, metrics-elb.rb has more features than metrics-elb-full.rb
(such as --period and --statistics, which are not available in the `-full`
variant) and supports the AWS-SDK v2, which helps for #240

CHANGELOG.md

@@ -4,6 +4,12 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 This CHANGELOG follows the format listed [here](https://github.com/sensu-plugins/community/blob/master/HOW_WE_CHANGELOG.md)
 
 ## [Unreleased]
+### Breaking Changes
+- metrics-elb-full.rb: removed in favor of metrics-elb.rb, which is slightly more configurable and uses the AWS-SDK v2 already. Compared to metrics-elb-full.rb, metrics-elb.rb no longer takes --aws-access-key, --aws-secret-access-key flags, Authentication should be configured per [here](https://github.com/sensu-plugins/sensu-plugins-aws/blob/master/README.md#authentication) (@multani)
+- metrics-elb.rb: honors the --fetch_age flag which now looks up values 60 seconds in the past by default. This was the intended behavior, as documented in the NOTES section (@multani)
+
+### Fixed
+- metrics-elb.rb: properly handle the --scheme and --fetch_age flags (@multani)
 
 ## [10.2.0] - 2018-01-20
 ### Added

bin/metrics-elb.rb

@@ -52,7 +52,7 @@ class ELBMetrics < Sensu::Plugin::Metric::CLI::Graphite
          description: 'Metric naming scheme, text to prepend to metric',
          short: '-s SCHEME',
          long: '--scheme SCHEME',
-         default: ''
+         default: 'loadbalancer'
 
   option :fetch_age,
          description: 'How long ago to fetch metrics for',
@@ -106,8 +106,8 @@ def cloud_watch_metric(metric_name, value, load_balancer_name)
         }
       ],
       statistics: [value],
-      start_time: config[:end_time] - config[:period],
-      end_time: config[:end_time],
+      start_time: config[:end_time] - config[:fetch_age] - config[:period],
+      end_time: config[:end_time] - config[:fetch_age],
       period: config[:period]
     )
   end
@@ -117,8 +117,17 @@ def print_statistics(load_balancer_name, statistics)
     static_value = {}
     statistics.each do |key, static|
       r = cloud_watch_metric(key, static, load_balancer_name)
-      static_value['loadbalancer.' + load_balancer_name + '.' + key + '.' + static] = static
-      result['loadbalancer.' + load_balancer_name + '.' + key + '.' + static] = r[:datapoints][0] unless r[:datapoints][0].nil?
+      keys =
+        if config[:scheme].nil?
+          []
+        else
+          [config[:scheme]]
+        end
+      keys.concat [load_balancer_name, key, static]
+      metric_key = keys.join('.')
+
+      static_value[metric_key] = static
+      result[metric_key] = r[:datapoints][0] unless r[:datapoints][0].nil?
     end
     result.each do |key, value|
       output key.downcase.to_s, value[static_value[key].downcase], value[:timestamp].to_i