fix: add 'receiver.mongodb.removeDatabaseResourceAttr' feature gate

.chloggen/mongodbreceiver-duplicate-attribute-24972.yaml

@@ -7,7 +7,7 @@ change_type: 'bug_fix'
 component: mongodbreceiver
 
 # A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
-note: Remove duplicate database name attribute, database name reported as a datapoint attribute and as a resource attribute, one of them should be removed
+note: "add `receiver.mongodb.removeDatabaseResourceAttr` Alpha feature gate to remove duplicate database name attribute"
 
 # Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
 issues: [24972]

receiver/mongodbreceiver/README.md

@@ -76,3 +76,15 @@ The following metric are available with versions:
 - `mongodb.index.access.count` >= 4.0
 
 Details about the metrics produced by this receiver can be found in [metadata.yaml](./metadata.yaml)
+
+## Feature gate configurations
+See the [Collector feature gates](https://github.com/open-telemetry/opentelemetry-collector/blob/main/featuregate/README.md#collector-feature-gates) for an overview of feature gates in the collector.
+
+**ALPHA**: `receiver.mongodb.removeDatabaseResourceAttr`
+
+The feature gate `receiver.mongodb.removeDatabaseResourceAttr` once enabled will remove database name resource attribute, 
+because both resource and datapoint attributes are called database.
+
+This feature gate will eventually be enabled by default, and eventually the old implementation will be removed. It aims
+to give users time to migrate to the new implementation. The target release for this featuregate to be enabled by default
+is 0.93.0.

receiver/mongodbreceiver/documentation.md

@@ -397,3 +397,9 @@ The amount of time that the server has been running.
 | Unit | Metric Type | Value Type | Aggregation Temporality | Monotonic |
 | ---- | ----------- | ---------- | ----------------------- | --------- |
 | ms | Sum | Int | Cumulative | true |
+
+## Resource Attributes
+
+| Name | Description | Values | Enabled |
+| ---- | ----------- | ------ | ------- |
+| database | The name of a database. | Any Str | false |

receiver/mongodbreceiver/internal/metadata/testdata/config.yaml

@@ -61,6 +61,9 @@ all_set:
       enabled: true
     mongodb.uptime:
       enabled: true
+  resource_attributes:
+    database:
+      enabled: true
 none_set:
   metrics:
     mongodb.cache.operations:
@@ -123,3 +126,6 @@ none_set:
       enabled: false
     mongodb.uptime:
       enabled: false
+  resource_attributes:
+    database:
+      enabled: false

receiver/mongodbreceiver/metadata.yaml

@@ -8,6 +8,14 @@ status:
   codeowners:
     active: [djaglowski, schmikei]
 
+resource_attributes:
+  database:
+    description: The name of a database.
+    enabled: false
+    type: string
+    warnings:
+      if_configured: This resource_attribute is deprecated and will be removed soon.
+
 attributes:
   database:
     description: The name of a database.

receiver/mongodbreceiver/scraper.go

@@ -12,6 +12,7 @@ import (
 	"github.com/hashicorp/go-version"
 	"go.mongodb.org/mongo-driver/bson"
 	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/pdata/pcommon"
 	"go.opentelemetry.io/collector/pdata/pmetric"
 	"go.opentelemetry.io/collector/receiver"
@@ -21,23 +22,49 @@ import (
 	"github.com/open-telemetry/opentelemetry-collector-contrib/receiver/mongodbreceiver/internal/metadata"
 )
 
-var unknownVersion = func() *version.Version { return version.Must(version.NewVersion("0.0")) }
+const (
+	readmeURL                    = "https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/receiver/mongodbreceiver/README.md"
+	removeDatabaseResourceAttrID = "receiver.mongodb.removeDatabaseResourceAttr"
+)
+
+var (
+	unknownVersion = func() *version.Version { return version.Must(version.NewVersion("0.0")) }
+
+	removeDatabaseResourceAttrFeatureGate = featuregate.GlobalRegistry().MustRegister(
+		removeDatabaseResourceAttrID,
+		featuregate.StageAlpha,
+		featuregate.WithRegisterDescription("Remove duplicate database name resource attribute"),
+		featuregate.WithRegisterReferenceURL("https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/24972"),
+		featuregate.WithRegisterFromVersion("v0.88.0"))
+)
 
 type mongodbScraper struct {
 	logger       *zap.Logger
 	config       *Config
 	client       client
 	mongoVersion *version.Version
 	mb           *metadata.MetricsBuilder
+
+	// removeDatabaseResourceAttr if enabled, will remove database resource attribute on database metrics
+	removeDatabaseResourceAttr bool
 }
 
 func newMongodbScraper(settings receiver.CreateSettings, config *Config) *mongodbScraper {
-	return &mongodbScraper{
-		logger:       settings.Logger,
-		config:       config,
-		mb:           metadata.NewMetricsBuilder(config.MetricsBuilderConfig, settings),
-		mongoVersion: unknownVersion(),
+	ms := &mongodbScraper{
+		logger:                     settings.Logger,
+		config:                     config,
+		mb:                         metadata.NewMetricsBuilder(config.MetricsBuilderConfig, settings),
+		mongoVersion:               unknownVersion(),
+		removeDatabaseResourceAttr: removeDatabaseResourceAttrFeatureGate.IsEnabled(),
+	}
+
+	if !ms.removeDatabaseResourceAttr {
+		settings.Logger.Warn(
+			fmt.Sprintf("Feature gate %s is not enabled. Please see the README for more information: %s", removeDatabaseResourceAttrID, readmeURL),
+		)
 	}
+
+	return ms
 }
 
 func (s *mongodbScraper) start(ctx context.Context, _ component.Host) error {
@@ -116,7 +143,15 @@ func (s *mongodbScraper) collectDatabase(ctx context.Context, now pcommon.Timest
 		return
 	}
 	s.recordNormalServerStats(now, serverStatus, databaseName, errs)
-	s.mb.EmitForResource()
+
+	emitWith := []metadata.ResourceMetricsOption{}
+	if !s.removeDatabaseResourceAttr {
+		rb := s.mb.NewResourceBuilder()
+		rb.SetDatabase(databaseName)
+		emitWith = append(emitWith, metadata.WithResource(rb.Emit()))
+	}
+
+	s.mb.EmitForResource(emitWith...)
 }
 
 func (s *mongodbScraper) collectAdminDatabase(ctx context.Context, now pcommon.Timestamp, errs *scrapererror.ScrapeErrors) {