Add template processor (#6494)

plugins/processors/template/template_metric.go

@@ -0,0 +1,28 @@
+package template
+
+import (
+	"github.com/influxdata/telegraf"
+	"time"
+)
+
+type TemplateMetric struct {
+	metric telegraf.Metric
+}
+
+func (m *TemplateMetric) Measurement() string {
+	return m.Measurement()
+}
+
+func (m *TemplateMetric) Tag(key string) string {
+	tagString, _ := m.metric.GetTag(key)
+	return tagString
+}
+
+func (m *TemplateMetric) Field(key string) interface{} {
+	field, _ := m.metric.GetField(key)
+	return field
+}
+
+func (m *TemplateMetric) Time() time.Time {
+	return m.metric.Time()
+}