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When a server S knows that some objects from a repository are available from a promisor remote X, S might want to suggest to a client C cloning or fetching the repo from S that C may use X directly instead of S for these objects. Note that this could happen both in the case S itself doesn't have the objects and borrows them from X, and in the case S has the objects but knows that X is better connected to the world (e.g., it is in a $LARGEINTERNETCOMPANY datacenter with petabit/s backbone connections) than S. Implementation of the latter case, which would require S to omit in its response the objects available on X, is left for future improvement though. Then C might or might not, want to get the objects from X. If S and C can agree on C using X directly, S can then omit objects that can be obtained from X when answering C's request. To allow S and C to agree and let each other know about C using X or not, let's introduce a new "promisor-remote" capability in the protocol v2, as well as a few new configuration variables: - "promisor.advertise" on the server side, and: - "promisor.acceptFromServer" on the client side. By default, or if "promisor.advertise" is set to 'false', a server S will not advertise the "promisor-remote" capability. If S doesn't advertise the "promisor-remote" capability, then a client C replying to S shouldn't advertise the "promisor-remote" capability either. If "promisor.advertise" is set to 'true', S will advertise its promisor remotes with a string like: promisor-remote=<pr-info>[;<pr-info>]... where each <pr-info> element contains information about a single promisor remote in the form: name=<pr-name>[,url=<pr-url>] where <pr-name> is the urlencoded name of a promisor remote and <pr-url> is the urlencoded URL of the promisor remote named <pr-name>. For now, the URL is passed in addition to the name. In the future, it might be possible to pass other information like a filter-spec that the client may use when cloning from S, or a token that the client may use when retrieving objects from X. It is C's responsibility to arrange how it can reach X though, so pieces of information that are usually outside Git's concern, like proxy configuration, must not be distributed over this protocol. It might also be possible in the future for "promisor.advertise" to have other values. For example a value like "onlyName" could prevent S from advertising URLs, which could help in case C should use a different URL for X than the URL S is using. (The URL S is using might be an internal one on the server side for example.) By default or if "promisor.acceptFromServer" is set to "None", C will not accept to use the promisor remotes that might have been advertised by S. In this case, C will not advertise any "promisor-remote" capability in its reply to S. If "promisor.acceptFromServer" is set to "All" and S advertised some promisor remotes, then on the contrary, C will accept to use all the promisor remotes that S advertised and C will reply with a string like: promisor-remote=<pr-name>[;<pr-name>]... where the <pr-name> elements are the urlencoded names of all the promisor remotes S advertised. In a following commit, other values for "promisor.acceptFromServer" will be implemented, so that C will be able to decide the promisor remotes it accepts depending on the name and URL it received from S. So even if that name and URL information is not used much right now, it will be needed soon. Helped-by: Taylor Blau <me@ttaylorr.com> Helped-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals.
Git is an Open Source project covered by the GNU General Public License version 2 (some parts of it are under different licenses, compatible with the GPLv2). It was originally written by Linus Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-<commandname>.txt for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with man gittutorial or git help tutorial, and the
documentation of each command with man git-<commandname> or git help <commandname>.
CVS users may also want to read Documentation/gitcvs-migration.txt
(man gitcvs-migration or git help cvs-migration if git is
installed).
The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org (read Documentation/SubmittingPatches for instructions on patch submission and Documentation/CodingGuidelines).
Those wishing to help with error message, usage and informational message
string translations (localization l10) should see po/README.md
(a po file is a Portable Object file that holds the translations).
To subscribe to the list, send an email to git+subscribe@vger.kernel.org (see https://subspace.kernel.org/subscribing.html for details). The mailing list archives are available at https://lore.kernel.org/git/, https://marc.info/?l=git and other archival sites.
Issues which are security relevant should be disclosed privately to the Git Security mailing list git-security@googlegroups.com.
The maintainer frequently sends the "What's cooking" reports that list the current status of various development topics to the mailing list. The discussion following them give a good reference for project status, development direction and remaining tasks.
The name "git" was given by Linus Torvalds when he wrote the very first version. He described the tool as "the stupid content tracker" and the name as (depending on your mood):
- random three-letter combination that is pronounceable, and not actually used by any common UNIX command. The fact that it is a mispronunciation of "get" may or may not be relevant.
- stupid. contemptible and despicable. simple. Take your pick from the dictionary of slang.
- "global information tracker": you're in a good mood, and it actually works for you. Angels sing, and a light suddenly fills the room.
- "goddamn idiotic truckload of sh*t": when it breaks