net/http: set Content-Length:0 for empty PATCH requests as with POST, PATCH

Sets Content-Length:0 for nil bodies in PATCH requests, as we already do for  POST and PUT requests.

RFC 2616 mentions that unless a method’s Content-Length is forbidden it can send one.
In the wild, we’ve found that Microsoft Azure’s DataLake Gen2 storage API deliberately rejects PATCH requests without a Content-Length, yet there is no workaround for setting that header when trying to flush the content of a file which was uploaded in a previous request.

Fixes #40978

Change-Id: Ib0a623b907d827a1c5ee431dca3c41024fa291c5
GitHub-Last-Rev: 12a3903f2bc22bcc4f5f8e2abcc3922b612b8871
GitHub-Pull-Request: golang/go#40991
Run-TryBot: Emmanuel Odeke <>
TryBot-Result: Gobot Gobot <>
Reviewed-by: Emmanuel Odeke <>
2 files changed
tree: 1d807a3fddceb63edb1e836e469d06692cfd6294
  1. .gitattributes
  2. .github/
  3. .gitignore
  11. api/
  12. doc/
  13. favicon.ico
  14. lib/
  15. misc/
  16. robots.txt
  17. src/
  18. test/

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