lib/sidekiq_prometheus.rb in sidekiq_prometheus-0.8.1 vs lib/sidekiq_prometheus.rb in sidekiq_prometheus-0.9.0

@@ -18,10 +18,25 @@
     attr_accessor :base_labels
 
     # @return [Hash] Custom labels applied to specific metrics
     attr_accessor :custom_labels
 
+    # @return [Array] Custom metrics that will be registered on setup.
+    # @example
+    #   [
+    #     {
+    #       name: :metric_name,
+    #       type: :prometheus_metric_type,
+    #       docstring: 'Description of the metric',
+    #       base_labels : { label: 'value' },
+    #     }
+    #   ]
+    # @note Each element of the array is a hash and must have the required keys: `:name`, `:type`, and `:docstring`.
+    #   The values for `:name` and `:type` should be symbols and `:docstring` should be a string.
+    #   `base_labels` is optional and, if used, must be a hash of labels that will be included on every instance of this metric.
+    attr_accessor :custom_metrics
+
     # @return [Boolean] Setting to control enabling/disabling GC metrics. Default: true
     attr_accessor :gc_metrics_enabled
 
     # @return [Boolean] Setting to control enabling/disabling global metrics. Default: true
     attr_accessor :global_metrics_enabled
@@ -40,47 +55,46 @@
     attr_writer :client
 
     # Orverride the default Prometheus Metric Registry
     # @return [Prometheus::Client::Registry]
     attr_writer :registry
+
+    # @private
+    attr_writer :setup_complete
   end
 
   self.gc_metrics_enabled = true
   self.periodic_metrics_enabled = true
   self.global_metrics_enabled = true
   self.periodic_reporting_interval = 30
   self.metrics_port = 9359
   self.custom_labels = {}
+  self.custom_metrics = []
 
   module_function
 
   ##
   # @return Prometheus::Client
   def client
     @client ||= Prometheus::Client
   end
 
   ##
-  # Configure SidekiqPrometheus
+  # Configure SidekiqPrometheus and setup for reporting
   # @example
   #   SidekiqPrometheus.configure do |config|
   #     config.base_labels = { service: 'images_api' }
   #     config.custom_labels = { sidekiq_job_count: { object_klass: nil } }
   #     config.gc_metrics_enabled = true
   #   end
   def configure
     yield self
-  end
-
-  ##
-  # Configure and call setup immediately after
-  def configure!
-    yield self
     setup
   end
 
-  ##
+  alias configure! configure
+
   # Helper method for +gc_metrics_enabled+ configuration setting
   # @return [Boolean] defaults to true
   def gc_metrics_enabled?
     gc_metrics_enabled
   end
@@ -115,21 +129,37 @@
 
   ##
   # Prometheus client metric registry
   # @return [Prometheus::Client::Registry]
   def registry
-    @registry ||= client.registry
+    @registry ||= client::Registry.new
   end
 
   ##
+  # Register custom metrics
+  # Internal method called by +setup+. This method should not be called from application code in most cases.
+  def register_custom_metrics
+    return if custom_metrics.empty?
+
+    raise SidekiqPrometheus::Error, 'custom_metrics is not an array.' unless custom_metrics.is_a?(Array)
+
+    SidekiqPrometheus::Metrics.register_metrics(custom_metrics)
+  end
+
+  ##
   # register metrics and instrument sidekiq
   def setup
+    return false if @setup_complete
     SidekiqPrometheus::Metrics.register_sidekiq_job_metrics
     SidekiqPrometheus::Metrics.register_sidekiq_gc_metric if gc_metrics_enabled?
     SidekiqPrometheus::Metrics.register_sidekiq_worker_gc_metrics if gc_metrics_enabled? && periodic_metrics_enabled?
     SidekiqPrometheus::Metrics.register_sidekiq_global_metrics if global_metrics_enabled? && periodic_metrics_enabled?
+    register_custom_metrics
+
     sidekiq_setup
+
+    self.setup_complete = true
   end
 
   ##
   # Add Prometheus instrumentation to sidekiq
   def sidekiq_setup
@@ -161,16 +191,12 @@
         Port: SidekiqPrometheus.metrics_port,
         BindAddress: '127.0.0.1',
       )
     end
   end
-
-  private
-
-  def metrics
-    SidekiqPrometheus::Metrics
-  end
 end
+
+class SidekiqPrometheus::Error < StandardError; end
 
 require 'sidekiq_prometheus/job_metrics'
 require 'sidekiq_prometheus/metrics'
 require 'sidekiq_prometheus/periodic_metrics'
 require 'sidekiq_prometheus/version'