git-fast-export

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



NAME
       git-fast-export - Git data exporter

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


DESCRIPTION
       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
       --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
           $ 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
       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
       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
       git-fast-import(1)

GIT
       Part of the git(1) suite



Git 2.30.0                         12/28/2020                 GIT-FAST-EXPORT(1)