Merge pull request #3 from meetcleo/PLT-XXX-cleanse-names

[PLT-XXX] Ensure metric names are valid Prometheus
meetcleo · Oct 13, 2023 · 146bed7 · 146bed7
2 parents 5c08148 + 2cf6193
commit 146bed7
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Showing 2 changed files with 12 additions and 5 deletions.
diff --git a/lib/statsd/instrument/prometheus/serializer.rb b/lib/statsd/instrument/prometheus/serializer.rb
@@ -6,6 +6,7 @@ module Prometheus
       class Serializer
         # Colon separated, but allows double-colon values, e.g. name:value, name.1:value.1, name:Module1::Module2::Class
         LABEL_EXTRACTOR = /^(?<name>[^\:]+)\:(?<value>.+)$/
+        INVALID_NAME_CHARACTERS = /[^a-zA-Z0-9:_]/
 
         def initialize(datagrams, application_name, subsystem)
           @datagrams = datagrams
@@ -20,6 +21,12 @@ def run
           ::Prometheus::WriteRequest.encode(::Prometheus::WriteRequest.new(timeseries: timeseries, metadata: []))
         end
 
+        class << self
+          def cleanse_name(name)
+            name.gsub(INVALID_NAME_CHARACTERS, "_")
+          end
+        end
+
         private
 
         attr_reader :datagrams, :current_time_ms, :pid, :hostname, :application_name, :subsystem
@@ -47,7 +54,7 @@ def default_prometheus_labels
         # This will prevent dup labels
         def labels_by_name(datagram)
           labels = default_prometheus_labels.clone
-          labels["__name__"] = ::Prometheus::Label.new(name: "__name__", value: datagram.name)
+          labels["__name__"] = ::Prometheus::Label.new(name: "__name__", value: self.class.cleanse_name(datagram.name))
           return labels unless datagram.tags
 
           extracted_labels_from_tags = datagram.tags.map do |tag|

diff --git a/test/prometheus/integration_test.rb b/test/prometheus/integration_test.rb
@@ -53,7 +53,7 @@ def test_mocked_request
               { name: "__meta_subsystem", value: "subsystem" },
               { name: "host", value: "" },
               { name: "pid", value: "" },
-              { name: "__name__", value: "counter.total" },
+              { name: "__name__", value: "counter_total" },
               { name: "source", value: "App::Main::Controller" },
               { name: "env", value: "test" },
             ],
@@ -64,9 +64,9 @@ def test_mocked_request
           },
           expected_metric("metrics_since_last_flush", 1.0),
           expected_metric("pre_aggregation_number_of_metrics_since_last_flush", 2.0),
-          expected_metric("number_of_requests_attempted.total", 1.0),
-          expected_metric("number_of_requests_succeeded_upto_previous_flush.total", 0.0),
-          expected_metric("number_of_metrics_dropped_due_to_buffer_full.total", 0.0),
+          expected_metric("number_of_requests_attempted_total", 1.0),
+          expected_metric("number_of_requests_succeeded_upto_previous_flush_total", 0.0),
+          expected_metric("number_of_metrics_dropped_due_to_buffer_full_total", 0.0),
           expected_metric("time_since_last_flush_initiated", -1),
         ],
         metadata: [],