prometheus exporters: Add add_metric_suffixes configuration option (#24260)

**Description:**
Add add_metric_suffixes configuration option, which can disable the
addition of type and unit suffixes.
This is backwards-compatible, since the default is true.

This is recommended by the specification for sum suffixes in
https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/compatibility/prometheus_and_openmetrics.md#sums
and allowed in metadata

https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/compatibility/prometheus_and_openmetrics.md#metric-metadata-1:

`Exporters SHOULD provide a configuration option to disable the addition
of _total suffixes.`

`The resulting unit SHOULD be added to the metric as OpenMetrics UNIT
metadata and as a suffix to the metric name unless the metric name
already contains the unit, or the unit MUST be omitted`

This deprecates the BuildPromCompliantName function in-favor of
BuildCompliantName, which includes the additional argument for
configuring suffixes.

**Link to tracking Issue:**

Fixes
#21743
Part of
#8950

---------

Co-authored-by: Dmitrii Anoshin <[email protected]>

Author: dashpole

.chloggen/prometheusexporters-normalization-config.yaml

@@ -0,0 +1,20 @@
+# Use this changelog template to create an entry for release notes.
+# If your change doesn't affect end users, such as a test fix or a tooling change,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: 'enhancement'
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: prometheusremotewriteexporter, prometheusexporter
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Add `add_metric_suffixes` configuration option, which can disable the addition of type and unit suffixes."
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [21743, 8950]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

exporter/prometheusexporter/README.md

@@ -33,6 +33,7 @@ The following settings can be optionally configured:
 - `resource_to_telemetry_conversion`
   - `enabled` (default = false): If `enabled` is `true`, all the resource attributes will be converted to metric labels by default.
 - `enable_open_metrics`: (default = `false`): If true, metrics will be exported using the OpenMetrics format. Exemplars are only exported in the OpenMetrics format, and only for histogram and monotonic sum (i.e. counter) metrics.
+- `add_metric_suffixes`: (default = `true`): If false, addition of type and unit suffixes is disabled.
 
 Example:
 
@@ -51,6 +52,7 @@ exporters:
     send_timestamps: true
     metric_expiration: 180m
     enable_open_metrics: true
+    add_metric_suffixes: false
     resource_to_telemetry_conversion:
       enabled: true
 ```

exporter/prometheusexporter/collector.go

@@ -30,18 +30,20 @@ type collector struct {
 	accumulator accumulator
 	logger      *zap.Logger
 
-	sendTimestamps bool
-	namespace      string
-	constLabels    prometheus.Labels
+	sendTimestamps    bool
+	addMetricSuffixes bool
+	namespace         string
+	constLabels       prometheus.Labels
 }
 
 func newCollector(config *Config, logger *zap.Logger) *collector {
 	return &collector{
-		accumulator:    newAccumulator(logger, config.MetricExpiration),
-		logger:         logger,
-		namespace:      prometheustranslator.CleanUpString(config.Namespace),
-		sendTimestamps: config.SendTimestamps,
-		constLabels:    config.ConstLabels,
+		accumulator:       newAccumulator(logger, config.MetricExpiration),
+		logger:            logger,
+		namespace:         prometheustranslator.CleanUpString(config.Namespace),
+		sendTimestamps:    config.SendTimestamps,
+		constLabels:       config.ConstLabels,
+		addMetricSuffixes: config.AddMetricSuffixes,
 	}
 }
 
@@ -127,7 +129,7 @@ func (c *collector) getMetricMetadata(metric pmetric.Metric, attributes pcommon.
 	}
 
 	return prometheus.NewDesc(
-		prometheustranslator.BuildPromCompliantName(metric, c.namespace),
+		prometheustranslator.BuildCompliantName(metric, c.namespace, c.addMetricSuffixes),
 		metric.Description(),
 		keys,
 		c.constLabels,

exporter/prometheusexporter/config.go

@@ -34,6 +34,9 @@ type Config struct {
 
 	// EnableOpenMetrics enables the use of the OpenMetrics encoding option for the prometheus exporter.
 	EnableOpenMetrics bool `mapstructure:"enable_open_metrics"`
+
+	// AddMetricSuffixes controls whether suffixes are added to metric names. Defaults to true.
+	AddMetricSuffixes bool `mapstructure:"add_metric_suffixes"`
 }
 
 var _ component.Config = (*Config)(nil)

exporter/prometheusexporter/config_test.go

@@ -50,8 +50,9 @@ func TestLoadConfig(t *testing.T) {
 					"label1":        "value1",
 					"another label": "spaced value",
 				},
-				SendTimestamps:   true,
-				MetricExpiration: 60 * time.Minute,
+				SendTimestamps:    true,
+				MetricExpiration:  60 * time.Minute,
+				AddMetricSuffixes: false,
 			},
 		},
 	}

exporter/prometheusexporter/factory.go

@@ -29,6 +29,7 @@ func createDefaultConfig() component.Config {
 		SendTimestamps:    false,
 		MetricExpiration:  time.Minute * 5,
 		EnableOpenMetrics: false,
+		AddMetricSuffixes: true,
 	}
 }
 

exporter/prometheusexporter/testdata/config.yaml

@@ -11,3 +11,4 @@ prometheus/2:
     "another label": spaced value
   send_timestamps: true
   metric_expiration: 60m
+  add_metric_suffixes: false

exporter/prometheusremotewriteexporter/README.md

@@ -50,6 +50,7 @@ The following settings can be optionally configured:
 - `headers`: additional headers attached to each HTTP request.
   - *Note the following headers cannot be changed: `Content-Encoding`, `Content-Type`, `X-Prometheus-Remote-Write-Version`, and `User-Agent`.*
 - `namespace`: prefix attached to each exported metric name.
+- `add_metric_suffixes`: If set to false, type and unit suffixes will not be added to metrics. Default: true.
 - `remote_write_queue`: fine tuning for queueing and sending of the outgoing remote writes.
   - `enabled`: enable the sending queue
   - `queue_size`: number of OTLP metrics that can be queued. Ignored if `enabled` is `false`

exporter/prometheusremotewriteexporter/config.go

@@ -42,6 +42,9 @@ type Config struct {
 
 	// CreatedMetric allows customizing creation of _created metrics
 	CreatedMetric *CreatedMetric `mapstructure:"export_created_metric,omitempty"`
+
+	// AddMetricSuffixes controls whether unit and type suffixes are added to metrics on export
+	AddMetricSuffixes bool `mapstructure:"add_metric_suffixes"`
 }
 
 type CreatedMetric struct {

exporter/prometheusremotewriteexporter/config_test.go

@@ -54,8 +54,9 @@ func TestLoadConfig(t *testing.T) {
 					QueueSize:    2000,
 					NumConsumers: 10,
 				},
-				Namespace:      "test-space",
-				ExternalLabels: map[string]string{"key1": "value1", "key2": "value2"},
+				AddMetricSuffixes: false,
+				Namespace:         "test-space",
+				ExternalLabels:    map[string]string{"key1": "value1", "key2": "value2"},
 				HTTPClientSettings: confighttp.HTTPClientSettings{
 					Endpoint: "localhost:8888",
 					TLSSetting: configtls.TLSClientSetting{