view hgext/fastexport.py @ 44682:9ce613d648de

rust-chg: add config validation and process returned instructions

This is the reimplementation of runinstructions() and main() in chg.c.

In Rust version, we only pass in early arguments to the server as the locator
doesn't know the full arguments. This should be fine since these arguments
are just passed in to _earlyparseopts() and _parseconfig(), which means the
server doesn't need full arguments.

Another difference is the handling of the "exit <code>" instruction. In Rust
version, we can simply reuse the connection instead of "exit(code)" as the
command error isn't displayed yet. That's because the client-side stdio is not
attached until the connection is validated. This behavior is cleaner than C,
but it also means that the early server exception wouldn't be propagated to
client because stderr isn't attached. So we might have to reconsider when to
attach/detach the server stdio.

Differential Revision: https://phab.mercurial-scm.org/D8381

# Copyright 2020 Joerg Sonnenberger <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""export repositories as git fast-import stream"""

# The format specification for fast-import streams can be found at
# https://git-scm.com/docs/git-fast-import#_input_format

from __future__ import absolute_import
import re

from mercurial.i18n import _
from mercurial.node import hex, nullrev
from mercurial.utils import stringutil
from mercurial import (
    error,
    pycompat,
    registrar,
    scmutil,
)
from .convert import convcmd

# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = b"ships-with-hg-core"

cmdtable = {}
command = registrar.command(cmdtable)

GIT_PERSON_PROHIBITED = re.compile(b'[<>\n"]')
GIT_EMAIL_PROHIBITED = re.compile(b"[<> \n]")


def convert_to_git_user(authormap, user, rev):
    mapped_user = authormap.get(user, user)
    user_person = stringutil.person(mapped_user)
    user_email = stringutil.email(mapped_user)
    if GIT_EMAIL_PROHIBITED.match(user_email) or GIT_PERSON_PROHIBITED.match(
        user_person
    ):
        raise error.Abort(
            _(b"Unable to parse user into person and email for revision " + rev)
        )
    if user_person:
        return b'"' + user_person + b'" <' + user_email + b'>'
    else:
        return b"<" + user_email + b">"


def convert_to_git_date(date):
    timestamp, utcoff = date
    tzsign = b"+" if utcoff < 0 else b"-"
    if utcoff % 60 != 0:
        raise error.Abort(
            _(b"UTC offset in %b is not an integer number of seconds") % (date,)
        )
    utcoff = abs(utcoff) // 60
    tzh = utcoff // 60
    tzmin = utcoff % 60
    return b"%d " % int(timestamp) + tzsign + b"%02d%02d" % (tzh, tzmin)


def convert_to_git_ref(branch):
    # XXX filter/map depending on git restrictions
    return b"refs/heads/" + branch


def write_data(buf, data, skip_newline):
    buf.append(b"data %d\n" % len(data))
    buf.append(data)
    if not skip_newline or data[-1:] != b"\n":
        buf.append(b"\n")


def export_commit(ui, repo, rev, marks, authormap):
    ctx = repo[rev]
    revid = ctx.hex()
    if revid in marks:
        ui.warn(_(b"warning: revision %s already exported, skipped\n") % revid)
        return
    parents = [p for p in ctx.parents() if p.rev() != nullrev]
    for p in parents:
        if p.hex() not in marks:
            ui.warn(
                _(b"warning: parent %s of %s has not been exported, skipped\n")
                % (p, revid)
            )
            return

    # For all files modified by the commit, check if they have already
    # been exported and otherwise dump the blob with the new mark.
    for fname in ctx.files():
        if fname not in ctx:
            continue
        filectx = ctx.filectx(fname)
        filerev = hex(filectx.filenode())
        if filerev not in marks:
            mark = len(marks) + 1
            marks[filerev] = mark
            data = filectx.data()
            buf = [b"blob\n", b"mark :%d\n" % mark]
            write_data(buf, data, False)
            ui.write(*buf, keepprogressbar=True)
            del buf

    # Assign a mark for the current revision for references by
    # latter merge commits.
    mark = len(marks) + 1
    marks[revid] = mark

    ref = convert_to_git_ref(ctx.branch())
    buf = [
        b"commit %s\n" % ref,
        b"mark :%d\n" % mark,
        b"committer %s %s\n"
        % (
            convert_to_git_user(authormap, ctx.user(), revid),
            convert_to_git_date(ctx.date()),
        ),
    ]
    write_data(buf, ctx.description(), True)
    if parents:
        buf.append(b"from :%d\n" % marks[parents[0].hex()])
    if len(parents) == 2:
        buf.append(b"merge :%d\n" % marks[parents[1].hex()])
        p0ctx = repo[parents[0]]
        files = ctx.manifest().diff(p0ctx.manifest())
    else:
        files = ctx.files()
    filebuf = []
    for fname in files:
        if fname not in ctx:
            filebuf.append((fname, b"D %s\n" % fname))
        else:
            filectx = ctx.filectx(fname)
            filerev = filectx.filenode()
            fileperm = b"755" if filectx.isexec() else b"644"
            changed = b"M %s :%d %s\n" % (fileperm, marks[hex(filerev)], fname)
            filebuf.append((fname, changed))
    filebuf.sort()
    buf.extend(changed for (fname, changed) in filebuf)
    del filebuf
    buf.append(b"\n")
    ui.write(*buf, keepprogressbar=True)
    del buf


isrev = re.compile(b"^[0-9a-f]{40}$")


@command(
    b"fastexport",
    [
        (b"r", b"rev", [], _(b"revisions to export"), _(b"REV")),
        (b"i", b"import-marks", b"", _(b"old marks file to read"), _(b"FILE")),
        (b"e", b"export-marks", b"", _(b"new marks file to write"), _(b"FILE")),
        (
            b"A",
            b"authormap",
            b"",
            _(b"remap usernames using this file"),
            _(b"FILE"),
        ),
    ],
    _(b"[OPTION]... [REV]..."),
    helpcategory=command.CATEGORY_IMPORT_EXPORT,
)
def fastexport(ui, repo, *revs, **opts):
    """export repository as git fast-import stream

    This command lets you dump a repository as a human-readable text stream.
    It can be piped into corresponding import routines like "git fast-import".
    Incremental dumps can be created by using marks files.
    """
    opts = pycompat.byteskwargs(opts)

    revs += tuple(opts.get(b"rev", []))
    if not revs:
        revs = scmutil.revrange(repo, [b":"])
    else:
        revs = scmutil.revrange(repo, revs)
    if not revs:
        raise error.Abort(_(b"no revisions matched"))
    authorfile = opts.get(b"authormap")
    if authorfile:
        authormap = convcmd.readauthormap(ui, authorfile)
    else:
        authormap = {}

    import_marks = opts.get(b"import_marks")
    marks = {}
    if import_marks:
        with open(import_marks, "rb") as import_marks_file:
            for line in import_marks_file:
                line = line.strip()
                if not isrev.match(line) or line in marks:
                    raise error.Abort(_(b"Corrupted marks file"))
                marks[line] = len(marks) + 1

    revs.sort()
    with ui.makeprogress(
        _(b"exporting"), unit=_(b"revisions"), total=len(revs)
    ) as progress:
        for rev in revs:
            export_commit(ui, repo, rev, marks, authormap)
            progress.increment()

    export_marks = opts.get(b"export_marks")
    if export_marks:
        with open(export_marks, "wb") as export_marks_file:
            output_marks = [None] * len(marks)
            for k, v in marks.items():
                output_marks[v - 1] = k
            for k in output_marks:
                export_marks_file.write(k + b"\n")