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Request for detailed documentation of git pack protocol

From
Jakub Narebski <jnareb@gmail.com>
Date
May 12, 2009, 21:29 UTC
Message-ID
<200905122329.15379.jnareb@gmail.com>

We have now proliferation of different (re)implementations of git: JGit in Java, Dulwich in Python, Grit in Ruby; and there are other planned: git# / managed git in C# (GSoC Mono project), ObjectiveGit in Objective-C (for iPhone IIRC). At some time they would reach the point (or reached it already) of implementing git-daemon... but currently the documentation of git protocol is lacking.

This can lead, as you can read from recent post on git mailing, to implementing details wrong (like Dulwich not using full SHA-1 where it should, leading to ordinary git clients to failing to fetch from it), or fail at best practices of implementation (like JGit last issue with deadlocking for multi_ack extension).

The current documentation of git protocol is very sparse; the docs
in Documentation/technical/pack-protocol.txt offer only a sketch of
exchange.  You can find more, including pkt-line format, a way sideband
is multiplexed, and how capabilities are negotiated between server and
client in design document for "smart" HTTP server, for example in
  Subject: Re: More on git over HTTP POST
  Message-ID: <20080803025602.GB27465@spearce.org>
  URL: http://thread.gmane.org/gmane.comp.version-control.git/91104/focus=91196

It would be really nice, I think, to have RFC for git pack protocol. And it would help avoid incompatibilities between different clients and servers. If the document would contain expected behaviour of client and server and Best Current Practices it would help avoid pitfals when implementing git-daemon in other implementation.

Perhaps in the future it could be sent for inclusion as "official" RFC to IETF? (Dreaming big).

Unfortunately I don't know enough about this area of code to write one myself.

-- 
Jakub Narebski
ShadeHawk or jnareb on #git
Poland
Next: Shawn O. Pearce
Message 1 of 66 in “Request for detailed documentation of git pack protocol”
  1. Jakub NarebskiMay 12, 2009
  2. Shawn O. PearceMay 12, 2009
  3. Jakub NarebskiMay 14, 2009
  4. Shawn O. PearceMay 14, 2009
  5. Andreas EricssonMay 14, 2009
  6. Linus TorvaldsMay 15, 2009
  7. Clemens BuchacherMay 15, 2009
  8. Nicolas PitreMay 14, 2009
  9. Jakub NarebskiMay 14, 2009
  10. Scott ChaconMay 14, 2009
  11. Shawn O. PearceMay 14, 2009
  12. Jakub NarebskiMay 14, 2009
  13. A Large Angry SCMMay 15, 2009
  14. Ealdwulf WuffingaMay 15, 2009
  15. Jakub NarebskiJun 2, 2009
  16. Shawn O. PearceJun 2, 2009
  17. Jakub NarebskiJun 3, 2009
  18. Shawn O. PearceJun 3, 2009
  19. Junio C HamanoJun 3, 2009
  20. Shawn O. PearceJun 3, 2009
  21. Jakub NarebskiJun 3, 2009
  22. Shawn O. PearceJun 3, 2009
  23. Shawn O. PearceJun 3, 2009
  24. Jakub NarebskiJun 3, 2009
  25. Shawn O. PearceJun 3, 2009
  26. Jakub NarebskiJun 3, 2009
  27. Shawn O. PearceJun 3, 2009
  28. Jakub NarebskiJun 3, 2009
  29. Shawn O. PearceJun 3, 2009
  30. Jakub NarebskiJun 3, 2009
  31. Shawn O. PearceJun 3, 2009
  32. Junio C HamanoJun 3, 2009
  33. Jakub NarebskiJun 3, 2009
  34. Andreas EricssonJun 4, 2009
  35. Junio C HamanoJun 4, 2009
  36. Scott ChaconJun 6, 2009
  37. Junio C HamanoJun 6, 2009
  38. Jakub NarebskiJun 6, 2009
  39. Tony FinchJun 3, 2009
  40. Junio C HamanoJun 3, 2009
  41. Johannes SixtJun 3, 2009
  42. Robin H. JohnsonJun 3, 2009
  43. Jakub NarebskiJun 3, 2009
  44. Shawn O. PearceJun 3, 2009
  45. Tony FinchJun 3, 2009
  46. Jakub NarebskiJun 3, 2009
  47. Tony FinchJun 3, 2009
  48. Jakub NarebskiJun 4, 2009
  49. Tony FinchJun 4, 2009
  50. Shawn O. PearceJun 4, 2009
  51. Jakub NarebskiJun 3, 2009
  52. Shawn O. PearceJun 3, 2009
  53. Jakub NarebskiJun 4, 2009
  54. Shawn O. PearceJun 4, 2009
  55. Shawn O. PearceJun 5, 2009
  56. Jakub NarebskiJun 5, 2009
  57. Jakub NarebskiJun 5, 2009
  58. Comments pack protocol description in "Git Community Book" (second round)Jakub Narebski, Jun 6, 2009
  59. Scott ChaconJun 6, 2009
  60. Jakub NarebskiJun 7, 2009
  61. Shawn O. PearceJun 7, 2009
  62. Shawn O. PearceJun 7, 2009
  63. Jakub NarebskiJun 13, 2009
  64. Shawn O. PearceJun 7, 2009
  65. Jakub NarebskiJun 9, 2009
  66. Shawn O. PearceJun 9, 2009

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