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 2021-08-27.  (At that time,
       the date of the most recent commit that was found in the
       repository was 2021-08-24.)  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 2.33.0.69.gc420321         08/27/2021             GIT-FAST-EXPORT(1)

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