Add option to specify case of label values added based on regexp subm…

…atches when performing combine action (#1640)

processor/metricstransformprocessor/README.md

@@ -56,6 +56,8 @@ transforms:
  new_name: <new_metric_name_inserted>
  # aggregation_type defines how combined data points will be aggregated; if action is combine, aggregation_type is required
  aggregation_type: {sum, mean, min, max}
+ # submatch_case specifies the case that should be used when adding label values based on regexp submatches when performing a combine action; leave blank to use the submatch value as is
+ submatch_case: {lower, upper}
  # operations contain a list of operations that will be performed on the selected metrics
  operations:
  # action defines the type of operation that will be performed, see examples below for more details
@@ -219,13 +221,14 @@ operations:
 ```yaml
 # convert a set of metrics for each http_method into a single metric with an http_method label, i.e.
 #
-# Web Service (*)/Total DELETE Requests iis.requests{http_method=DELETE}
-# Web Service (*)/Total GET Requests > iis.requests{http_method=GET}
-# Web Service (*)/Total POST Requests iis.requests{http_method=POST}
+# Web Service (*)/Total Delete Requests iis.requests{http_method=delete}
+# Web Service (*)/Total Get Requests > iis.requests{http_method=get}
+# Web Service (*)/Total Post Requests iis.requests{http_method=post}
 metric_names: ^Web Service \(\*\)/Total (?P<http_method>.*) Requests$
 match_type: regexp
 action: combine
 new_name: iis.requests
+submatch_case: lower
 operations:
  ...
 ```

processor/metricstransformprocessor/config.go

@@ -45,6 +45,9 @@ const (
 
  // NewValueFieldName is the mapstructure field name for NewValue field
  NewValueFieldName = "new_value"
+
+ // SubmatchCaseFieldName is the mapstructure field name for SubmatchCase field
+ SubmatchCaseFieldName = "submatch_case"
 )
 
 // Config defines configuration for Resource processor.
@@ -77,6 +80,9 @@ type Transform struct {
  // REQUIRED only if Action is COMBINE.
  AggregationType AggregationType `mapstructure:"aggregation_type"`
 
+ // SubmatchCase specifies what case to use for label values created from regexp submatches.
+ SubmatchCase SubmatchCase `mapstructure:"submatch_case"`
+
  // Operations contains a list of operations that will be performed on the selected metric.
  Operations []Operation `mapstructure:"operations"`
 }
@@ -129,7 +135,7 @@ type ValueAction struct {
  NewValue string `mapstructure:"new_value"`
 }
 
-// ConfigAction is the enum to capture the two types of actions to perform on a metric.
+// ConfigAction is the enum to capture the type of action to perform on a metric.
 type ConfigAction string
 
 const (
@@ -243,3 +249,26 @@ func (mt MatchType) isValid() bool {
 
  return false
 }
+
+// SubmatchCase is the enum to capture the two types of case changes to apply to submatches.
+type SubmatchCase string
+
+const (
+ // Lower is the SubmatchCase for lower casing the submatch.
+ Lower SubmatchCase = "lower"
+
+ // Upper is the SubmatchCase for upper casing the submatch.
+ Upper SubmatchCase = "upper"
+)
+
+var SubmatchCases = []SubmatchCase{Lower, Upper}
+
+func (sc SubmatchCase) isValid() bool {
+ for _, submatchCase := range SubmatchCases {
+ if sc == submatchCase {
+ return true
+ }
+ }
+
+ return false
+}

processor/metricstransformprocessor/config_test.go

@@ -123,8 +123,9 @@ func TestLoadingFullConfig(t *testing.T) {
  Include: "^regexp (?P<my_label>.*)$",
  MatchType: "regexp",
  },
- Action: "combine",
- NewName: "combined_metric_name",
+ Action: "combine",
+ NewName: "combined_metric_name",
+ SubmatchCase: "lower",
  },
  },
  },

processor/metricstransformprocessor/factory.go

@@ -105,6 +105,10 @@ func validateConfiguration(config *Config) error {
  return fmt.Errorf("%q must be in %q", AggregationTypeFieldName, AggregationTypes)
  }
 
+ if transform.SubmatchCase != "" && !transform.SubmatchCase.isValid() {
+ return fmt.Errorf("%q must be in %q", SubmatchCaseFieldName, SubmatchCases)
+ }
+
  for i, op := range transform.Operations {
  if !op.Action.isValid() {
  return fmt.Errorf("operation %v: %q must be in %q", i+1, ActionFieldName, OperationActions)

processor/metricstransformprocessor/factory_test.go

@@ -109,6 +109,11 @@ func TestCreateProcessors(t *testing.T) {
  succeed: false,
  errorMessage: fmt.Sprintf("operation %v: %q must be in %q", 1, AggregationTypeFieldName, AggregationTypes),
  },
+ {
+ configName: "config_invalid_submatchcase.yaml",
+ succeed: false,
+ errorMessage: fmt.Sprintf("%q must be in %q", SubmatchCaseFieldName, SubmatchCases),
+ },
  }
 
  for _, test := range tests {

processor/metricstransformprocessor/metrics_transform_processor.go

@@ -19,6 +19,7 @@ import (
  "fmt"
  "regexp"
  "strconv"
+ "strings"
 
  metricspb "github.com/census-instrumentation/opencensus-proto/gen-go/metrics/v1"
  "go.opentelemetry.io/collector/consumer/consumerdata"
@@ -42,6 +43,7 @@ type internalTransform struct {
  Action ConfigAction
  NewName string
  AggregationType AggregationType
+ SubmatchCase SubmatchCase
  Operations []internalOperation
 }
 
@@ -245,6 +247,7 @@ func (mtp *metricsTransformProcessor) combine(matchedMetrics []*match, transform
  // append label values based on regex submatches
  for i := 1; i < len(match.submatches)/2; i++ {
  submatch := match.metric.MetricDescriptor.Name[match.submatches[2*i]:match.submatches[2*i+1]]
+ submatch = replaceCaseOfSubmatch(transform.SubmatchCase, submatch)
  ts.LabelValues = append(ts.LabelValues, &metricspb.LabelValue{Value: submatch, HasValue: (submatch != "")})
  }
 
@@ -261,6 +264,17 @@ func (mtp *metricsTransformProcessor) combine(matchedMetrics []*match, transform
  return combinedMetric
 }
 
+func replaceCaseOfSubmatch(replacement SubmatchCase, submatch string) string {
+ switch replacement {
+ case Lower:
+ return strings.ToLower(submatch)
+ case Upper:
+ return strings.ToUpper(submatch)
+ }
+
+ return submatch
+}
+
 // removeMatchedMetricsAndAppendCombined removes the set of matched metrics from metrics and appends the combined metric at the end.
 func (mtp *metricsTransformProcessor) removeMatchedMetricsAndAppendCombined(metrics []*metricspb.Metric, matchedMetrics []*match, combined *metricspb.Metric) []*metricspb.Metric {
  filteredMetrics := make([]*metricspb.Metric, 0, len(metrics)-len(matchedMetrics))

processor/metricstransformprocessor/metrics_transform_processor_testcases_test.go

@@ -856,13 +856,14 @@ var (
  name: "combine",
  transforms: []internalTransform{
  {
- MetricIncludeFilter: internalFilterRegexp{include: regexp.MustCompile("^(metric)(?P<namedsubmatch>[12])$")},
+ MetricIncludeFilter: internalFilterRegexp{include: regexp.MustCompile("^([mM]etric)(?P<namedsubmatch>[12])$")},
  Action: Combine,
  NewName: "new",
+ SubmatchCase: "lower",
  },
  },
  in: []*metricspb.Metric{
- metricBuilder().setName("metric1").
+ metricBuilder().setName("Metric1").
  setDataType(metricspb.MetricDescriptor_GAUGE_INT64).
  addTimeseries(1, nil).addInt64Point(0, 1, 1).
  build(),
@@ -930,13 +931,14 @@ var (
  name: "combine_single_match",
  transforms: []internalTransform{
  {
- MetricIncludeFilter: internalFilterRegexp{include: regexp.MustCompile("^(metric)(?P<namedsubmatch>[1])$")},
+ MetricIncludeFilter: internalFilterRegexp{include: regexp.MustCompile("^([mM]etric)(?P<namedsubmatch>[1])$")},
  Action: Combine,
  NewName: "new",
+ SubmatchCase: "upper",
  },
  },
  in: []*metricspb.Metric{
- metricBuilder().setName("metric1").
+ metricBuilder().setName("Metric1").
  setDataType(metricspb.MetricDescriptor_GAUGE_INT64).
  addTimeseries(1, nil).addInt64Point(0, 1, 1).
  build(),
@@ -961,7 +963,7 @@ var (
  metricBuilder().setName("new").
  setLabels([]string{"$1", "namedsubmatch"}).
  setDataType(metricspb.MetricDescriptor_GAUGE_INT64).
- addTimeseries(1, []string{"metric", "1"}).addInt64Point(0, 1, 1).
+ addTimeseries(1, []string{"METRIC", "1"}).addInt64Point(0, 1, 1).
  build(),
  },
  },

processor/metricstransformprocessor/testdata/config_full.yaml

@@ -49,6 +49,7 @@ processors:
  match_type: regexp
  action: combine
  new_name: combined_metric_name
+ submatch_case: lower
 
 exporters:
  exampleexporter:

processor/metricstransformprocessor/testdata/config_invalid_submatchcase.yaml

@@ -0,0 +1,24 @@
+receivers:
+ examplereceiver:
+
+processors:
+ metricstransform:
+ transforms:
+ - include: old_name
+ action: combine
+ new_name: new_name
+ submatch_case: invalid
+
+exporters:
+ exampleexporter:
+
+service:
+ pipelines:
+ traces:
+ receivers: [examplereceiver]
+ processors: [metricstransform]
+ exporters: [exampleexporter]
+ metrics:
+ receivers: [examplereceiver]
+ processors: [metricstransform]
+ exporters: [exampleexporter]