git-fast-export(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | ANONYMIZING | LIMITATIONS | SEE ALSO | GIT | COLOPHON

GIT-FAST-EXPORT(1)               Git Manual               GIT-FAST-EXPORT(1)

NAME top

       git-fast-export - Git data exporter

SYNOPSIS top

       git fast-export [<options>] | git fast-import

DESCRIPTION top

       This program dumps the given revisions in a form suitable to be piped
       into git fast-import.

       You can use it as a human-readable bundle replacement (see
       git-bundle(1)), or as a format that can be edited before being fed to
       git fast-import in order to do history rewrites (an ability relied on
       by tools like git filter-repo).

OPTIONS top

       --progress=<n>
           Insert progress statements every <n> objects, to be shown by git
           fast-import during import.

       --signed-tags=(verbatim|warn|warn-strip|strip|abort)
           Specify how to handle signed tags. Since any transformation after
           the export can change the tag names (which can also happen when
           excluding revisions) the signatures will not match.

           When asking to abort (which is the default), this program will
           die when encountering a signed tag. With strip, the tags will
           silently be made unsigned, with warn-strip they will be made
           unsigned but a warning will be displayed, with verbatim, they
           will be silently exported and with warn, they will be exported,
           but you will see a warning.

       --tag-of-filtered-object=(abort|drop|rewrite)
           Specify how to handle tags whose tagged object is filtered out.
           Since revisions and files to export can be limited by path,
           tagged objects may be filtered completely.

           When asking to abort (which is the default), this program will
           die when encountering such a tag. With drop it will omit such
           tags from the output. With rewrite, if the tagged object is a
           commit, it will rewrite the tag to tag an ancestor commit (via
           parent rewriting; see git-rev-list(1))

       -M, -C
           Perform move and/or copy detection, as described in the
           git-diff(1) manual page, and use it to generate rename and copy
           commands in the output dump.

           Note that earlier versions of this command did not complain and
           produced incorrect results if you gave these options.

       --export-marks=<file>
           Dumps the internal marks table to <file> when complete. Marks are
           written one per line as :markid SHA-1. Only marks for revisions
           are dumped; marks for blobs are ignored. Backends can use this
           file to validate imports after they have been completed, or to
           save the marks table across incremental runs. As <file> is only
           opened and truncated at completion, the same path can also be
           safely given to --import-marks. The file will not be written if
           no new object has been marked/exported.

       --import-marks=<file>
           Before processing any input, load the marks specified in <file>.
           The input file must exist, must be readable, and must use the
           same format as produced by --export-marks.

       --mark-tags
           In addition to labelling blobs and commits with mark ids, also
           label tags. This is useful in conjunction with --export-marks and
           --import-marks, and is also useful (and necessary) for exporting
           of nested tags. It does not hurt other cases and would be the
           default, but many fast-import frontends are not prepared to
           accept tags with mark identifiers.

           Any commits (or tags) that have already been marked will not be
           exported again. If the backend uses a similar --import-marks
           file, this allows for incremental bidirectional exporting of the
           repository by keeping the marks the same across runs.

       --fake-missing-tagger
           Some old repositories have tags without a tagger. The fast-import
           protocol was pretty strict about that, and did not allow that. So
           fake a tagger to be able to fast-import the output.

       --use-done-feature
           Start the stream with a feature done stanza, and terminate it
           with a done command.

       --no-data
           Skip output of blob objects and instead refer to blobs via their
           original SHA-1 hash. This is useful when rewriting the directory
           structure or history of a repository without touching the
           contents of individual files. Note that the resulting stream can
           only be used by a repository which already contains the necessary
           objects.

       --full-tree
           This option will cause fast-export to issue a "deleteall"
           directive for each commit followed by a full list of all files in
           the commit (as opposed to just listing the files which are
           different from the commit’s first parent).

       --anonymize
           Anonymize the contents of the repository while still retaining
           the shape of the history and stored tree. See the section on
           ANONYMIZING below.

       --anonymize-map=<from>[:<to>]
           Convert token <from> to <to> in the anonymized output. If <to> is
           omitted, map <from> to itself (i.e., do not anonymize it). See
           the section on ANONYMIZING below.

       --reference-excluded-parents
           By default, running a command such as git fast-export
           master~5..master will not include the commit master~5 and will
           make master~4 no longer have master~5 as a parent (though both
           the old master~4 and new master~4 will have all the same files).
           Use --reference-excluded-parents to instead have the stream refer
           to commits in the excluded range of history by their sha1sum.
           Note that the resulting stream can only be used by a repository
           which already contains the necessary parent commits.

       --show-original-ids
           Add an extra directive to the output for commits and blobs,
           original-oid <SHA1SUM>. While such directives will likely be
           ignored by importers such as git-fast-import, it may be useful
           for intermediary filters (e.g. for rewriting commit messages
           which refer to older commits, or for stripping blobs by id).

       --reencode=(yes|no|abort)
           Specify how to handle encoding header in commit objects. When
           asking to abort (which is the default), this program will die
           when encountering such a commit object. With yes, the commit
           message will be re-encoded into UTF-8. With no, the original
           encoding will be preserved.

       --refspec
           Apply the specified refspec to each ref exported. Multiple of
           them can be specified.

       [<git-rev-list-args>...]
           A list of arguments, acceptable to git rev-parse and git
           rev-list, that specifies the specific objects and references to
           export. For example, master~10..master causes the current master
           reference to be exported along with all objects added since its
           10th ancestor commit and (unless the --reference-excluded-parents
           option is specified) all files common to master~9 and master~10.

EXAMPLES top

           $ git fast-export --all | (cd /empty/repository && git fast-import)

       This will export the whole repository and import it into the existing
       empty repository. Except for reencoding commits that are not in
       UTF-8, it would be a one-to-one mirror.

           $ git fast-export master~5..master |
                   sed "s|refs/heads/master|refs/heads/other|" |
                   git fast-import

       This makes a new branch called other from master~5..master (i.e. if
       master has linear history, it will take the last 5 commits).

       Note that this assumes that none of the blobs and commit messages
       referenced by that revision range contains the string
       refs/heads/master.

ANONYMIZING top

       If the --anonymize option is given, git will attempt to remove all
       identifying information from the repository while still retaining
       enough of the original tree and history patterns to reproduce some
       bugs. The goal is that a git bug which is found on a private
       repository will persist in the anonymized repository, and the latter
       can be shared with git developers to help solve the bug.

       With this option, git will replace all refnames, paths, blob
       contents, commit and tag messages, names, and email addresses in the
       output with anonymized data. Two instances of the same string will be
       replaced equivalently (e.g., two commits with the same author will
       have the same anonymized author in the output, but bear no
       resemblance to the original author string). The relationship between
       commits, branches, and tags is retained, as well as the commit
       timestamps (but the commit messages and refnames bear no resemblance
       to the originals). The relative makeup of the tree is retained (e.g.,
       if you have a root tree with 10 files and 3 trees, so will the
       output), but their names and the contents of the files will be
       replaced.

       If you think you have found a git bug, you can start by exporting an
       anonymized stream of the whole repository:

           $ git fast-export --anonymize --all >anon-stream

       Then confirm that the bug persists in a repository created from that
       stream (many bugs will not, as they really do depend on the exact
       repository contents):

           $ git init anon-repo
           $ cd anon-repo
           $ git fast-import <../anon-stream
           $ ... test your bug ...

       If the anonymized repository shows the bug, it may be worth sharing
       anon-stream along with a regular bug report. Note that the anonymized
       stream compresses very well, so gzipping it is encouraged. If you
       want to examine the stream to see that it does not contain any
       private data, you can peruse it directly before sending. You may also
       want to try:

           $ perl -pe 's/\d+/X/g' <anon-stream | sort -u | less

       which shows all of the unique lines (with numbers converted to "X",
       to collapse "User 0", "User 1", etc into "User X"). This produces a
       much smaller output, and it is usually easy to quickly confirm that
       there is no private data in the stream.

       Reproducing some bugs may require referencing particular commits or
       paths, which becomes challenging after refnames and paths have been
       anonymized. You can ask for a particular token to be left as-is or
       mapped to a new value. For example, if you have a bug which
       reproduces with git rev-list sensitive -- secret.c, you can run:

           $ git fast-export --anonymize --all \
                 --anonymize-map=sensitive:foo \
                 --anonymize-map=secret.c:bar.c \
                 >stream

       After importing the stream, you can then run git rev-list foo --
       bar.c in the anonymized repository.

       Note that paths and refnames are split into tokens at slash
       boundaries. The command above would anonymize subdir/secret.c as
       something like path123/bar.c; you could then search for bar.c in the
       anonymized repository to determine the final pathname.

       To make referencing the final pathname simpler, you can map each path
       component; so if you also anonymize subdir to publicdir, then the
       final pathname would be publicdir/bar.c.

LIMITATIONS top

       Since git fast-import cannot tag trees, you will not be able to
       export the linux.git repository completely, as it contains a tag
       referencing a tree instead of a commit.

SEE ALSO top

       git-fast-import(1)

GIT top

       Part of the git(1) suite

COLOPHON top

       This page is part of the git (Git distributed version control system)
       project.  Information about the project can be found at 
       ⟨http://git-scm.com/⟩.  If you have a bug report for this manual page,
       see ⟨http://git-scm.com/community⟩.  This page was obtained from the
       project's upstream Git repository ⟨https://github.com/git/git.git⟩ on
       2020-08-13.  (At that time, the date of the most recent commit that
       was found in the repository was 2020-08-11.)  If you discover any
       rendering problems in this HTML version of the page, or you believe
       there is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

Git 2.28.0.202.g7814e8           08/12/2020               GIT-FAST-EXPORT(1)

Pages that refer to this page: git(1) , git-fast-import(1) , gitremote-helpers(1) , gitremote-helpers(7)