internal.go 1.2 KB

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  1. // Copyright 2017, OpenCensus Authors
  2. //
  3. // Licensed under the Apache License, Version 2.0 (the "License");
  4. // you may not use this file except in compliance with the License.
  5. // You may obtain a copy of the License at
  6. //
  7. // http://www.apache.org/licenses/LICENSE-2.0
  8. //
  9. // Unless required by applicable law or agreed to in writing, software
  10. // distributed under the License is distributed on an "AS IS" BASIS,
  11. // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12. // See the License for the specific language governing permissions and
  13. // limitations under the License.
  14. package internal // import "go.opencensus.io/internal"
  15. import (
  16. "fmt"
  17. "time"
  18. opencensus "go.opencensus.io"
  19. )
  20. // UserAgent is the user agent to be added to the outgoing
  21. // requests from the exporters.
  22. var UserAgent = fmt.Sprintf("opencensus-go/%s", opencensus.Version())
  23. // MonotonicEndTime returns the end time at present
  24. // but offset from start, monotonically.
  25. //
  26. // The monotonic clock is used in subtractions hence
  27. // the duration since start added back to start gives
  28. // end as a monotonic time.
  29. // See https://golang.org/pkg/time/#hdr-Monotonic_Clocks
  30. func MonotonicEndTime(start time.Time) time.Time {
  31. return start.Add(time.Now().Sub(start))
  32. }