git-commit-vandalism/contrib/svn-fe/svn-fe.txt
Elijah Newren 9df53c5de6 Recommend git-filter-repo instead of git-filter-branch
filter-branch suffers from a deluge of disguised dangers that disfigure
history rewrites (i.e. deviate from the deliberate changes).  Many of
these problems are unobtrusive and can easily go undiscovered until the
new repository is in use.  This can result in problems ranging from an
even messier history than what led folks to filter-branch in the first
place, to data loss or corruption.  These issues cannot be backward
compatibly fixed, so add a warning to both filter-branch and its manpage
recommending that another tool (such as filter-repo) be used instead.

Also, update other manpages that referenced filter-branch.  Several of
these needed updates even if we could continue recommending
filter-branch, either due to implying that something was unique to
filter-branch when it applied more generally to all history rewriting
tools (e.g. BFG, reposurgeon, fast-import, filter-repo), or because
something about filter-branch was used as an example despite other more
commonly known examples now existing.  Reword these sections to fix
these issues and to avoid recommending filter-branch.

Finally, remove the section explaining BFG Repo Cleaner as an
alternative to filter-branch.  I feel somewhat bad about this,
especially since I feel like I learned so much from BFG that I put to
good use in filter-repo (which is much more than I can say for
filter-branch), but keeping that section presented a few problems:
  * In order to recommend that people quit using filter-branch, we need
    to provide them a recomendation for something else to use that
    can handle all the same types of rewrites.  To my knowledge,
    filter-repo is the only such tool.  So it needs to be mentioned.
  * I don't want to give conflicting recommendations to users
  * If we recommend two tools, we shouldn't expect users to learn both
    and pick which one to use; we should explain which problems one
    can solve that the other can't or when one is much faster than
    the other.
  * BFG and filter-repo have similar performance
  * All filtering types that BFG can do, filter-repo can also do.  In
    fact, filter-repo comes with a reimplementation of BFG named
    bfg-ish which provides the same user-interface as BFG but with
    several bugfixes and new features that are hard to implement in
    BFG due to its technical underpinnings.
While I could still mention both tools, it seems like I would need to
provide some kind of comparison and I would ultimately just say that
filter-repo can do everything BFG can, so ultimately it seems that it
is just better to remove that section altogether.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-09-05 13:01:48 -07:00

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svn-fe(1)
=========
NAME
----
svn-fe - convert an SVN "dumpfile" to a fast-import stream
SYNOPSIS
--------
[verse]
mkfifo backchannel &&
svnadmin dump --deltas REPO |
svn-fe [url] 3<backchannel |
git fast-import --cat-blob-fd=3 3>backchannel
DESCRIPTION
-----------
Converts a Subversion dumpfile into input suitable for
git-fast-import(1) and similar importers. REPO is a path to a
Subversion repository mirrored on the local disk. Remote Subversion
repositories can be mirrored on local disk using the `svnsync`
command.
Note: this tool is very young. The details of its commandline
interface may change in backward incompatible ways.
INPUT FORMAT
------------
Subversion's repository dump format is documented in full in
`notes/dump-load-format.txt` from the Subversion source tree.
Files in this format can be generated using the 'svnadmin dump' or
'svk admin dump' command.
OUTPUT FORMAT
-------------
The fast-import format is documented by the git-fast-import(1)
manual page.
NOTES
-----
Subversion dumps do not record a separate author and committer for
each revision, nor do they record a separate display name and email
address for each author. Like git-svn(1), 'svn-fe' will use the name
---------
user <user@UUID>
---------
as committer, where 'user' is the value of the `svn:author` property
and 'UUID' the repository's identifier.
To support incremental imports, 'svn-fe' puts a `git-svn-id` line at
the end of each commit log message if passed a URL on the command
line. This line has the form `git-svn-id: URL@REVNO UUID`.
The resulting repository will generally require further processing
to put each project in its own repository and to separate the history
of each branch. The 'git filter-repo --subdirectory-filter' command
may be useful for this purpose.
BUGS
----
Empty directories and unknown properties are silently discarded.
The exit status does not reflect whether an error was detected.
SEE ALSO
--------
git-svn(1), svn2git(1), svk(1), git-filter-repo(1), git-fast-import(1),
https://svn.apache.org/repos/asf/subversion/trunk/notes/dump-load-format.txt