add influx_uint_support support to outputs.influxdb

plugins/outputs/influxdb/influxdb.go

@@ -45,6 +45,7 @@ type InfluxDB struct {
 	HTTPHeaders          map[string]string `toml:"http_headers"`
 	ContentEncoding      string            `toml:"content_encoding"`
 	SkipDatabaseCreation bool              `toml:"skip_database_creation"`
+	InfluxUintSupport    bool              `toml:"influx_uint_support"`
 
 	// Path to CA file
 	SSLCA string `toml:"ssl_ca"`
@@ -119,6 +120,12 @@ var sampleConfig = `
   ## HTTP Content-Encoding for write request body, can be set to "gzip" to
   ## compress body or "identity" to apply no encoding.
   # content_encoding = "identity"
+
+  ## When true, Telegraf will output unsigned integers as unsigned values,
+  ## i.e.: "42u".  You will need a version of InfluxDB supporting unsigned
+  ## integer values.  Enabling this option will result in field type errors if
+  ## existing data has been written.
+  # influx_uint_support = false
 `
 
 func (i *InfluxDB) Connect() error {
@@ -134,7 +141,13 @@ func (i *InfluxDB) Connect() error {
 		urls = append(urls, defaultURL)
 	}
 
+	var typeSupport influx.FieldTypeSupport
+	if i.InfluxUintSupport {
+		typeSupport = typeSupport + influx.UintSupport
+	}
+
 	i.serializer = influx.NewSerializer()
+	i.serializer.SetFieldTypeSupport(typeSupport)
 
 	for _, u := range urls {
 		u, err := url.Parse(u)