Merge pull request #9 from scribd/jimp/rubocop

apply rubocop recommendations

Author: jim80net

.gitignore

@@ -1 +1,2 @@
 .rspec
+.idea

Gemfile

@@ -1,12 +1,14 @@
+# frozen_string_literal: true
+
 source 'https://rubygems.org'
 ruby '2.5.8'
 
-gem 'redis'
 gem 'dogapi'
+gem 'redis'
 
 group :development, :test do
+  gem 'guard-rspec'
   gem 'pry'
   gem 'rspec'
-  gem 'guard-rspec'
   gem 'timecop'
 end

Guardfile

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # A sample Guardfile
 # More info at https://github.com/guard/guard#readme
 
@@ -24,8 +26,8 @@
 #  * zeus: 'zeus rspec' (requires the server to be started separately)
 #  * 'just' rspec: 'rspec'
 
-guard :rspec, cmd: "bundle exec rspec" do
-  require "guard/rspec/dsl"
+guard :rspec, cmd: 'bundle exec rspec' do
+  require 'guard/rspec/dsl'
   dsl = Guard::RSpec::Dsl.new(self)
 
   # Feel free to open issues for suggestions and improvements
@@ -39,5 +41,4 @@ guard :rspec, cmd: "bundle exec rspec" do
   # Ruby files
   ruby = dsl.ruby
   dsl.watch_spec_files_for(ruby.lib_files)
-
 end

inject_slow_query.rb

@@ -1,4 +1,6 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: true
+
 # WARNING: This will lock up CPU on the target Redis instance. Never run against production.
 #
 # Copyright 2020 Scribd, Inc.
@@ -20,20 +22,20 @@
   milliseconds = ARGV[0].to_i
 end
 
-SCRIPT =<<HEREDOC
--- From https://medium.com/@stockholmux/simulating-a-slow-command-with-node-redis-and-lua-efadbf913cd9
-local aTempKey = "a-temp-key"
-local cycles
-redis.call("SET",aTempKey,"1")
-redis.call("PEXPIRE",aTempKey, #{milliseconds})
-for i = 0, #{15000 * milliseconds}, 1 do
-	local apttl = redis.call("PTTL",aTempKey)
-	cycles = i;
-	if apttl == 0 then
-		break;
-	end
-end
-return cycles
+SCRIPT = <<~HEREDOC
+  -- From https://medium.com/@stockholmux/simulating-a-slow-command-with-node-redis-and-lua-efadbf913cd9
+  local aTempKey = "a-temp-key"
+  local cycles
+  redis.call("SET",aTempKey,"1")
+  redis.call("PEXPIRE",aTempKey, #{milliseconds})
+  for i = 0, #{15_000 * milliseconds}, 1 do
+  	local apttl = redis.call("PTTL",aTempKey)
+  	cycles = i;
+  	if apttl == 0 then
+  		break;
+  	end
+  end
+  return cycles
 HEREDOC
 
 LOGGER.info REDIS.eval(SCRIPT)

lambda_function.rb

@@ -1,4 +1,6 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: true
+
 # Copyright 2020 Scribd, Inc.
 
 require 'logger'
@@ -11,7 +13,7 @@
 
 def event_time
   # DateTime because Time does not natively parse AWS CloudWatch Event time
-  DateTime.rfc3339(@event.fetch("time", DateTime.now.rfc3339))
+  DateTime.rfc3339(@event.fetch('time', DateTime.now.rfc3339))
 end
 
 def log_context
@@ -22,15 +24,14 @@ def log_context
   LOGGER.info "Event time: #{event_time}."
 end
 
-
 def lambda_handler(event: {}, context: {})
   @event = event
   log_context
 
   ssm_path = ENV.fetch('SSM_PATH', false)
   if ssm_path
     require 'aws-sdk-ssm'
-    resp = Aws::SSM::Client.new().get_parameters_by_path(
+    resp = Aws::SSM::Client.new.get_parameters_by_path(
       path: "/#{ssm_path}/",
       recursive: true,
       with_decryption: true
@@ -64,6 +65,4 @@ def lambda_handler(event: {}, context: {})
   nil
 end
 
-if __FILE__ == $0
-  lambda_handler
-end
+lambda_handler if __FILE__ == $PROGRAM_NAME

lib/slowlog_check.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Copyright 2020 Scribd, Inc.
 require 'logger'
 
@@ -8,16 +10,17 @@ class SlowlogCheck
 
   def initialize(params = {})
     @ddog = params.fetch(:ddog)
-    @redis= SlowlogCheck::Redis.new(params.fetch(:redis))
+    @redis = SlowlogCheck::Redis.new(params.fetch(:redis))
     @metricname = params.fetch(:metricname)
     @namespace = params.fetch(:namespace)
     @env = params.fetch(:env)
   end
 
   def status_or_error(resp)
-    return resp[1].fetch("status") if resp[1].key?("status")
-    return resp[1].fetch("errors") if resp[1].key?("errors")
-    return resp
+    return resp[1].fetch('status') if resp[1].key?('status')
+    return resp[1].fetch('errors') if resp[1].key?('errors')
+
+    resp
   end
 
   def last_datadog_metrics_submitted_by_me_in_the_last_2_hours
@@ -27,7 +30,8 @@ def last_datadog_metrics_submitted_by_me_in_the_last_2_hours
       Time.now
     )
 
-    raise "Error getting last datadog metric submitted by me" unless status_or_error(resp) == "ok"
+    raise 'Error getting last datadog metric submitted by me' unless status_or_error(resp) == 'ok'
+
     resp
   end
 
@@ -38,15 +42,15 @@ def minute_precision(time)
   end
 
   def last_datadog_metric
-    series = last_datadog_metrics_submitted_by_me_in_the_last_2_hours[1].fetch("series")
+    series = last_datadog_metrics_submitted_by_me_in_the_last_2_hours[1].fetch('series')
     if series == [] # First invocation
-      return minute_precision(Time.now - 3600)
+      minute_precision(Time.now - 3600)
     else
       minute_precision(
         Time.at(
           series
             .first
-            .fetch("pointlist")
+            .fetch('pointlist')
             .map { |x| x[0] }
             .max
             .to_i / 1000
@@ -57,6 +61,7 @@ def last_datadog_metric
 
   def last_time_submitted
     return @last_time_submitted if defined? @last_time_submitted
+
     @last_time_submitted = last_datadog_metric
   end
 
@@ -68,7 +73,6 @@ def slowlog_microseconds(slowlog)
     slowlog[2]
   end
 
-
   def reporting_interval
     now_i = minute_precision(Time.now).to_i - 60
     start_time_i = last_time_submitted.to_i + 60
@@ -105,7 +109,6 @@ def add_metric_to_bucket(prior, new)
     }
   end
 
-
   def empty_values
     {
       values: [],
@@ -137,7 +140,7 @@ def pad_results_with_zero(report)
       commands_to_zero = @seen_commands.keys - new_commands.keys
       commands_to_zero.each do |command|
         # inject_zeroing_commands
-        report[timebucket].merge!({command => empty_values})
+        report[timebucket].merge!({ command => empty_values })
         # And remove it from the seen_commands queue
         @seen_commands.delete(command)
       end
@@ -218,7 +221,7 @@ def emit_point(params)
         tags: tags
       }
     )
-    raise "Error submitting metric for #{@redis.replication_group}" unless status_or_error(resp) == "ok"
+    raise "Error submitting metric for #{@redis.replication_group}" unless status_or_error(resp) == 'ok'
 
     # Sigh. After doing all the work to pass around Time objects, dogapi-rb changes this to an integer.
     @last_time_submitted = Time.at(points.first[0])
@@ -236,7 +239,7 @@ def ship_slowlogs
         all_metrics = timebucket.fetch(command)
 
         # Emit most metrics
-        [:avg, :count, :median, :min, :max].each do |metric|
+        %i[avg count median min max].each do |metric|
           emit_point(
             metric: metric.to_s,
             type: metric == :count ? 'rate' : 'gauge',
@@ -251,76 +254,72 @@ def ship_slowlogs
           points: [[timestamp, all_metrics.fetch(:_95percentile)]],
           tags: default_tags.merge(command: command)
         )
-
       end
     end
   end
 
-
   ##
   # Metadata
 
   def metric_metadatas
-    [
-      'avg',
-      'median',
-      'min',
-      'max',
-      '95percentile'
-    ].map { |metric|
+    %w[
+      avg
+      median
+      min
+      max
+      95percentile
+    ].map do |metric|
       {
-        "name" => @metricname + '.' + metric,
-        "description" => "slowlog duration #{metric} (µs)",
-        "short_name" => "#{metric} (µs)",
-        "integration" => nil,
-        "statsd_interval" => 60,
-        "per_unit" => nil,
-        "type" => "gauge",
-        "unit" => "microsecond"
+        'name' => @metricname + '.' + metric,
+        'description' => "slowlog duration #{metric} (µs)",
+        'short_name' => "#{metric} (µs)",
+        'integration' => nil,
+        'statsd_interval' => 60,
+        'per_unit' => nil,
+        'type' => 'gauge',
+        'unit' => 'microsecond'
       }
-    }.push(
+    end.push(
       {
-        "name" => @metricname + '.count',
-        "type" => 'rate',
-        "description" => 'slowlog entries per minute',
-        "short_name" => 'per minute',
-        "per_unit" => 'minute',
-        "integration" => nil,
-        "unit" => 'entry',
-        "statsd_interval" => 60
+        'name' => @metricname + '.count',
+        'type' => 'rate',
+        'description' => 'slowlog entries per minute',
+        'short_name' => 'per minute',
+        'per_unit' => 'minute',
+        'integration' => nil,
+        'unit' => 'entry',
+        'statsd_interval' => 60
       }
     )
   end
 
   def get_metadatas
-    [
-      'avg',
-      'median',
-      'min',
-      'max',
-      '95percentile',
-      'count'
+    %w[
+      avg
+      median
+      min
+      max
+      95percentile
+      count
     ].map do |metric|
       name = @metricname + '.' + metric
       @ddog.get_metadata(name)[1]
-        .merge("name" => name)
+           .merge('name' => name)
     end
   end
 
   def diff_metadatas
     metric_metadatas - get_metadatas
   end
 
-
   def update_metadatas
     diff_metadatas.each do |metadata|
-      name = metadata.delete("name")
+      name = metadata.delete('name')
       resp = @ddog.update_metadata(
         name,
-        metadata.transform_keys { |key| key.to_sym }
+        metadata.transform_keys(&:to_sym)
       )
       LOGGER.info "Updating metadata for #{name} #{status_or_error(resp)}"
     end
   end
-
 end