Add ability to exclude db/bucket tag from influxdb outputs (#6184)

plugins/outputs/influxdb/README.md

@@ -23,6 +23,9 @@ The InfluxDB output plugin writes metrics to the [InfluxDB v1.x] HTTP or UDP ser
   ## tag is not set the 'database' option is used as the default.
   # database_tag = ""
 
+  ## If true, the database tag will not be added to the metric.
+  # exclude_database_tag = false
+
   ## If true, no CREATE DATABASE queries will be sent.  Set to true when using
   ## Telegraf with a user without permissions to create databases or when the
   ## database already exists.

plugins/outputs/influxdb/http.go

@@ -94,6 +94,7 @@ type HTTPConfig struct {
 	ContentEncoding      string
 	Database             string
 	DatabaseTag          string
+	ExcludeDatabaseTag   bool
 	RetentionPolicy      string
 	Consistency          string
 	SkipDatabaseCreation bool
@@ -250,6 +251,10 @@ func (c *httpClient) Write(ctx context.Context, metrics []telegraf.Metric) error
 				batches[db] = make([]telegraf.Metric, 0)
 			}
 
+			if c.config.ExcludeDatabaseTag {
+				metric.RemoveTag(c.config.DatabaseTag)
+			}
+
 			batches[db] = append(batches[db], metric)
 		}
 

plugins/outputs/influxdb/influxdb.go

@@ -38,6 +38,7 @@ type InfluxDB struct {
 	Password             string
 	Database             string
 	DatabaseTag          string `toml:"database_tag"`
+	ExcludeDatabaseTag   bool   `toml:"exclude_database_tag"`
 	UserAgent            string
 	RetentionPolicy      string
 	WriteConsistency     string
@@ -77,6 +78,9 @@ var sampleConfig = `
   ## tag is not set the 'database' option is used as the default.
   # database_tag = ""
 
+  ## If true, the database tag will not be added to the metric.
+  # exclude_database_tag = false
+
   ## If true, no CREATE DATABASE queries will be sent.  Set to true when using
   ## Telegraf with a user without permissions to create databases or when the
   ## database already exists.
@@ -262,6 +266,7 @@ func (i *InfluxDB) httpClient(ctx context.Context, url *url.URL, proxy *url.URL)
 		Headers:              i.HTTPHeaders,
 		Database:             i.Database,
 		DatabaseTag:          i.DatabaseTag,
+		ExcludeDatabaseTag:   i.ExcludeDatabaseTag,
 		SkipDatabaseCreation: i.SkipDatabaseCreation,
 		RetentionPolicy:      i.RetentionPolicy,
 		Consistency:          i.WriteConsistency,