From dead06c454d6c86cb269cd6e98c9a7599fc71315 Mon Sep 17 00:00:00 2001
From: Andrey Novikov <envek@envek.name>
Date: Mon, 11 Dec 2023 21:16:54 +0900
Subject: [PATCH] Map metric aggregation setting from Yabeda to Prometheus-mmap

---
 lib/yabeda/prometheus/mmap/adapter.rb | 17 ++++++++++++++++-
 spec/yabeda/prometheus/mmap_spec.rb   |  4 ++--
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/lib/yabeda/prometheus/mmap/adapter.rb b/lib/yabeda/prometheus/mmap/adapter.rb
index 7e66a7a..ea15db7 100644
--- a/lib/yabeda/prometheus/mmap/adapter.rb
+++ b/lib/yabeda/prometheus/mmap/adapter.rb
@@ -36,7 +36,7 @@ def register_gauge!(metric)
             build_name(metric),
             metric.comment,
             build_tags(metric.tags),
-            metric.aggregation || :all
+            gauge_aggregation_mode(metric.aggregation)
           )
         end
 
@@ -87,6 +87,21 @@ def debug!
           end
         end
 
+        private
+
+        def gauge_aggregation_mode(yabeda_mode)
+          case yabeda_mode
+          when nil, :most_recent # TODO: Switch to most_recent when supported: https://gitlab.com/gitlab-org/ruby/gems/prometheus-client-mmap/-/issues/36
+            :all
+          when :min, :max, :all, :liveall
+            yabeda_mode
+          when :sum
+            :livesum
+          else
+            raise ArgumentError, "Unsupported gauge aggregation mode #{yabeda_mode.inspect}"
+          end
+        end
+
         Yabeda.register_adapter(:prometheus, new)
       end
     end
diff --git a/spec/yabeda/prometheus/mmap_spec.rb b/spec/yabeda/prometheus/mmap_spec.rb
index e6d3758..2ded663 100644
--- a/spec/yabeda/prometheus/mmap_spec.rb
+++ b/spec/yabeda/prometheus/mmap_spec.rb
@@ -14,7 +14,7 @@
       gauge :gauge,
             comment: 'Gauge',
             tags: [:gtag],
-            aggregation: :max
+            aggregation: :sum
 
       histogram :histogram,
                 comment: 'Histogram',
@@ -49,7 +49,7 @@
         .adapters[:prometheus].registry
         .instance_variable_get(:@metrics)[:test_gauge]
         .instance_variable_get(:@multiprocess_mode)
-      ).to eq(:max)
+      ).to eq(:livesum)
     end
   end