func()

in spectator/meter/id.go [31:78]

• 43 lines of code
• 9 McCabe index (conditional complexity)

func (id *Id) MapKey() string {
	id.keyOnce.Do(func() {
		// if the key was set directly during Id construction, then do not
		// compute a value.
		if id.key != "" {
			return
		}

		buf := builderPool.Get().(*strings.Builder)
		buf.Reset()
		defer builderPool.Put(buf)

		const errKey = "ERR"
		id.key = func() string {
			_, err := buf.WriteString(id.name)
			if err != nil {
				return errKey
			}
			keys := make([]string, 0, len(id.tags))
			for k := range id.tags {
				keys = append(keys, k)
			}
			sort.Strings(keys)

			for _, k := range keys {
				v := id.tags[k]
				_, err = buf.WriteRune('|')
				if err != nil {
					return errKey
				}
				_, err = buf.WriteString(k)
				if err != nil {
					return errKey
				}
				_, err = buf.WriteRune('|')
				if err != nil {
					return errKey
				}
				_, err = buf.WriteString(v)
				if err != nil {
					return errKey
				}
			}
			return buf.String()
		}()
	})
	return id.key
}