Allow count connector to count by attributes

.chloggen/count-by-attributes.yaml

@@ -0,0 +1,16 @@
+# 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: countconnector
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add ability to count by attributes
+
+# One or more tracking issues related to the change
+issues: [19432]
+
+# (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:

connector/countconnector/README.md

@@ -62,11 +62,15 @@ Optionally, emit custom counts by defining metrics under one or more of the foll
 - `datapoints`
 - `logs`
 
-Under each custom metric name, specify one or more conditions using [OTTL Syntax].
-Data that matches any one of the conditions will be counted. i.e. Conditions are ORed together.
-
 Optionally, specify a description for the metric.
 
+Note: If any custom metrics are defined for a data type, the default metric will not be emitted.
+
+#### Conditions
+
+Conditions may be specified for custom metrics. If specified, data that matches any one
+of the conditions will be counted. i.e. Conditions are ORed together.
+
 ```yaml
 receivers:
   foo:
@@ -82,7 +86,29 @@ connectors:
           - 'name == "prodevent"'
 ```
 
-Note: If any custom metrics are defined for a data type, the default metric will not be emitted.
+#### Attributes
+
+`spans`, `spanevents`, `datapoints`, and `logs` may be counted according to attributes.
+
+If attributes are specified for custom metrics, a separate count will be generated for each unique
+set of attribute values. Each count will be emitted as a data point on the same metric.
+
+Optionally, include a `default_value` for an attribute, to count data that does not contain the attribute.
+
+```yaml
+receivers:
+  foo:
+exporters:
+  bar:
+connectors:
+  count:
+    logs:
+      my.log.count:
+        description: The number of logs from each environment.
+        attributes:
+          - key: env
+            default_value: unspecified_environment
+```
 
 ### Example Usage
 
@@ -177,6 +203,32 @@ service:
       exporters: [bar]
 ```
 
+Count logs with a severity of ERROR or higher. Maintain a separate count for each environment.
+
+```yaml
+receivers:
+  foo:
+exporters:
+  bar:
+connectors:
+  count:
+    logs:
+      my.error.log.count:
+        description: Error+ logs.
+        conditions:
+          - `severity_number >= SEVERITY_NUMBER_ERROR`
+        attributes:
+          - key: env
+service:
+  pipelines:
+    logs:
+      receivers: [foo]
+      exporters: [count]
+    metrics:
+      receivers: [count]
+      exporters: [bar]
+```
+
 Count all spans and span events (default behavior). Count metrics and data points based on the `env` attribute.
 
 ```yaml

connector/countconnector/config.go

@@ -39,11 +39,17 @@ const (
 
 // Config for the connector
 type Config struct {
-	Spans      map[string]MetricInfo `mapstructure:"spans"`
-	SpanEvents map[string]MetricInfo `mapstructure:"spanevents"`
-	Metrics    map[string]MetricInfo `mapstructure:"metrics"`
-	DataPoints map[string]MetricInfo `mapstructure:"datapoints"`
-	Logs       map[string]MetricInfo `mapstructure:"logs"`
+	Spans      map[string]MetricInfoWithAttributes `mapstructure:"spans"`
+	SpanEvents map[string]MetricInfoWithAttributes `mapstructure:"spanevents"`
+	Metrics    map[string]MetricInfo               `mapstructure:"metrics"`
+	DataPoints map[string]MetricInfoWithAttributes `mapstructure:"datapoints"`
+	Logs       map[string]MetricInfoWithAttributes `mapstructure:"logs"`
+}
+
+// MetricInfoWithAttributes for a data type
+type MetricInfoWithAttributes struct {
+	MetricInfo `mapstructure:",squash"`
+	Attributes []AttributeConfig `mapstructure:"attributes"`
 }
 
 // MetricInfo for a data type
@@ -52,6 +58,11 @@ type MetricInfo struct {
 	Conditions  []string `mapstructure:"conditions"`
 }
 
+type AttributeConfig struct {
+	Key          string `mapstructure:"key"`
+	DefaultValue string `mapstructure:"default_value"`
+}
+
 func (c *Config) Validate() error {
 	for name, info := range c.Spans {
 		if name == "" {
@@ -64,6 +75,9 @@ func (c *Config) Validate() error {
 		if _, err = parseConditions(parser, info.Conditions); err != nil {
 			return fmt.Errorf("spans condition: metric %q: %w", name, err)
 		}
+		if err := info.validateAttributes(); err != nil {
+			return fmt.Errorf("spans attributes: metric %q: %w", name, err)
+		}
 	}
 	for name, info := range c.SpanEvents {
 		if name == "" {
@@ -76,6 +90,9 @@ func (c *Config) Validate() error {
 		if _, err = parseConditions(parser, info.Conditions); err != nil {
 			return fmt.Errorf("spanevents condition: metric %q: %w", name, err)
 		}
+		if err := info.validateAttributes(); err != nil {
+			return fmt.Errorf("spans attributes: metric %q: %w", name, err)
+		}
 	}
 	for name, info := range c.Metrics {
 		if name == "" {
@@ -101,6 +118,9 @@ func (c *Config) Validate() error {
 		if _, err = parseConditions(parser, info.Conditions); err != nil {
 			return fmt.Errorf("datapoints condition: metric %q: %w", name, err)
 		}
+		if err := info.validateAttributes(); err != nil {
+			return fmt.Errorf("spans attributes: metric %q: %w", name, err)
+		}
 	}
 	for name, info := range c.Logs {
 		if name == "" {
@@ -113,6 +133,18 @@ func (c *Config) Validate() error {
 		if _, err = parseConditions(parser, info.Conditions); err != nil {
 			return fmt.Errorf("logs condition: metric %q: %w", name, err)
 		}
+		if err := info.validateAttributes(); err != nil {
+			return fmt.Errorf("spans attributes: metric %q: %w", name, err)
+		}
+	}
+	return nil
+}
+
+func (i *MetricInfoWithAttributes) validateAttributes() error {
+	for _, attr := range i.Attributes {
+		if attr.Key == "" {
+			return fmt.Errorf("attribute key missing")
+		}
 	}
 	return nil
 }
@@ -148,18 +180,22 @@ func (c *Config) Unmarshal(componentParser *confmap.Conf) error {
 	return nil
 }
 
-func defaultSpansConfig() map[string]MetricInfo {
-	return map[string]MetricInfo{
+func defaultSpansConfig() map[string]MetricInfoWithAttributes {
+	return map[string]MetricInfoWithAttributes{
 		defaultMetricNameSpans: {
-			Description: defaultMetricDescSpans,
+			MetricInfo: MetricInfo{
+				Description: defaultMetricDescSpans,
+			},
 		},
 	}
 }
 
-func defaultSpanEventsConfig() map[string]MetricInfo {
-	return map[string]MetricInfo{
+func defaultSpanEventsConfig() map[string]MetricInfoWithAttributes {
+	return map[string]MetricInfoWithAttributes{
 		defaultMetricNameSpanEvents: {
-			Description: defaultMetricDescSpanEvents,
+			MetricInfo: MetricInfo{
+				Description: defaultMetricDescSpanEvents,
+			},
 		},
 	}
 }
@@ -172,18 +208,22 @@ func defaultMetricsConfig() map[string]MetricInfo {
 	}
 }
 
-func defaultDataPointsConfig() map[string]MetricInfo {
-	return map[string]MetricInfo{
+func defaultDataPointsConfig() map[string]MetricInfoWithAttributes {
+	return map[string]MetricInfoWithAttributes{
 		defaultMetricNameDataPoints: {
-			Description: defaultMetricDescDataPoints,
+			MetricInfo: MetricInfo{
+				Description: defaultMetricDescDataPoints,
+			},
 		},
 	}
 }
 
-func defaultLogsConfig() map[string]MetricInfo {
-	return map[string]MetricInfo{
+func defaultLogsConfig() map[string]MetricInfoWithAttributes {
+	return map[string]MetricInfoWithAttributes{
 		defaultMetricNameLogs: {
-			Description: defaultMetricDescLogs,
+			MetricInfo: MetricInfo{
+				Description: defaultMetricDescLogs,
+			},
 		},
 	}
 }