Add new remote-bzr transport helper

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

contrib/remote-helpers/git-remote-bzr

@@ -0,0 +1,352 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2012 Felipe Contreras
+#
+
+#
+# Just copy to your ~/bin, or anywhere in your $PATH.
+# Then you can clone with:
+# % git clone bzr::/path/to/bzr/repo/or/url
+#
+# For example:
+# % git clone bzr::$HOME/myrepo
+# or
+# % git clone bzr::lp:myrepo
+#
+
+import sys
+
+import bzrlib
+bzrlib.initialize()
+
+import bzrlib.plugin
+bzrlib.plugin.load_plugins()
+
+import sys
+import os
+import json
+import re
+
+NAME_RE = re.compile('^([^<>]+)')
+AUTHOR_RE = re.compile('^([^<>]+?)? ?<([^<>]*)>$')
+
+def die(msg, *args):
+    sys.stderr.write('ERROR: %s\n' % (msg % args))
+    sys.exit(1)
+
+def warn(msg, *args):
+    sys.stderr.write('WARNING: %s\n' % (msg % args))
+
+def gittz(tz):
+    return '%+03d%02d' % (tz / 3600, tz % 3600 / 60)
+
+class Marks:
+
+    def __init__(self, path):
+        self.path = path
+        self.tips = {}
+        self.marks = {}
+        self.last_mark = 0
+        self.load()
+
+    def load(self):
+        if not os.path.exists(self.path):
+            return
+
+        tmp = json.load(open(self.path))
+        self.tips = tmp['tips']
+        self.marks = tmp['marks']
+        self.last_mark = tmp['last-mark']
+
+    def dict(self):
+        return { 'tips': self.tips, 'marks': self.marks, 'last-mark' : self.last_mark }
+
+    def store(self):
+        json.dump(self.dict(), open(self.path, 'w'))
+
+    def __str__(self):
+        return str(self.dict())
+
+    def from_rev(self, rev):
+        return self.marks[rev]
+
+    def next_mark(self):
+        self.last_mark += 1
+        return self.last_mark
+
+    def get_mark(self, rev):
+        self.last_mark += 1
+        self.marks[rev] = self.last_mark
+        return self.last_mark
+
+    def is_marked(self, rev):
+        return self.marks.has_key(rev)
+
+    def get_tip(self, branch):
+        return self.tips.get(branch, None)
+
+    def set_tip(self, branch, tip):
+        self.tips[branch] = tip
+
+class Parser:
+
+    def __init__(self, repo):
+        self.repo = repo
+        self.line = self.get_line()
+
+    def get_line(self):
+        return sys.stdin.readline().strip()
+
+    def __getitem__(self, i):
+        return self.line.split()[i]
+
+    def check(self, word):
+        return self.line.startswith(word)
+
+    def each_block(self, separator):
+        while self.line != separator:
+            yield self.line
+            self.line = self.get_line()
+
+    def __iter__(self):
+        return self.each_block('')
+
+    def next(self):
+        self.line = self.get_line()
+        if self.line == 'done':
+            self.line = None
+
+def rev_to_mark(rev):
+    global marks
+    return marks.from_rev(rev)
+
+def fixup_user(user):
+    name = mail = None
+    user = user.replace('"', '')
+    m = AUTHOR_RE.match(user)
+    if m:
+        name = m.group(1)
+        mail = m.group(2).strip()
+    else:
+        m = NAME_RE.match(user)
+        if m:
+            name = m.group(1).strip()
+
+    return '%s <%s>' % (name, mail)
+
+def get_filechanges(cur, prev):
+    modified = {}
+    removed = {}
+
+    changes = cur.changes_from(prev)
+
+    for path, fid, kind in changes.added:
+        modified[path] = fid
+    for path, fid, kind in changes.removed:
+        removed[path] = None
+    for path, fid, kind, mod, _ in changes.modified:
+        modified[path] = fid
+    for oldpath, newpath, fid, kind, mod, _ in changes.renamed:
+        removed[oldpath] = None
+        modified[newpath] = fid
+
+    return modified, removed
+
+def export_files(tree, files):
+    global marks, filenodes
+
+    final = []
+    for path, fid in files.iteritems():
+        h = tree.get_file_sha1(fid)
+
+        mode = '100644'
+
+        # is the blob already exported?
+        if h in filenodes:
+            mark = filenodes[h]
+        else:
+            d = tree.get_file_text(fid)
+
+            mark = marks.next_mark()
+            filenodes[h] = mark
+
+            print "blob"
+            print "mark :%u" % mark
+            print "data %d" % len(d)
+            print d
+
+        final.append((mode, mark, path))
+
+    return final
+
+def export_branch(branch, name):
+    global prefix, dirname
+
+    ref = '%s/heads/%s' % (prefix, name)
+    tip = marks.get_tip(name)
+
+    repo = branch.repository
+    repo.lock_read()
+    revs = branch.iter_merge_sorted_revisions(None, tip, 'exclude', 'forward')
+    count = 0
+
+    revs = [revid for revid, _, _, _ in revs if not marks.is_marked(revid)]
+
+    for revid in revs:
+
+        rev = repo.get_revision(revid)
+
+        parents = rev.parent_ids
+        time = rev.timestamp
+        tz = rev.timezone
+        committer = rev.committer.encode('utf-8')
+        committer = "%s %u %s" % (fixup_user(committer), time, gittz(tz))
+        author = committer
+        msg = rev.message.encode('utf-8')
+
+        msg += '\n'
+
+        if len(parents) == 0:
+            parent = bzrlib.revision.NULL_REVISION
+        else:
+            parent = parents[0]
+
+        cur_tree = repo.revision_tree(revid)
+        prev = repo.revision_tree(parent)
+        modified, removed = get_filechanges(cur_tree, prev)
+
+        modified_final = export_files(cur_tree, modified)
+
+        if len(parents) == 0:
+            print 'reset %s' % ref
+
+        print "commit %s" % ref
+        print "mark :%d" % (marks.get_mark(revid))
+        print "author %s" % (author)
+        print "committer %s" % (committer)
+        print "data %d" % (len(msg))
+        print msg
+
+        for i, p in enumerate(parents):
+            try:
+                m = rev_to_mark(p)
+            except KeyError:
+                # ghost?
+                continue
+            if i == 0:
+                print "from :%s" % m
+            else:
+                print "merge :%s" % m
+
+        for f in modified_final:
+            print "M %s :%u %s" % f
+        for f in removed:
+            print "D %s" % (f)
+        print
+
+        count += 1
+        if (count % 100 == 0):
+            print "progress revision %s (%d/%d)" % (revid, count, len(revs))
+            print "#############################################################"
+
+    repo.unlock()
+
+    revid = branch.last_revision()
+
+    # make sure the ref is updated
+    print "reset %s" % ref
+    print "from :%u" % rev_to_mark(revid)
+    print
+
+    marks.set_tip(name, revid)
+
+def export_tag(repo, name):
+    global tags
+    try:
+        print "reset refs/tags/%s" % name
+        print "from :%u" % rev_to_mark(tags[name])
+        print
+    except KeyError:
+        warn("TODO: fetch tag '%s'" % name)
+
+def do_import(parser):
+    global dirname
+
+    branch = parser.repo
+    path = os.path.join(dirname, 'marks-git')
+
+    print "feature done"
+    if os.path.exists(path):
+        print "feature import-marks=%s" % path
+    print "feature export-marks=%s" % path
+    sys.stdout.flush()
+
+    while parser.check('import'):
+        ref = parser[1]
+        if ref.startswith('refs/heads/'):
+            name = ref[len('refs/heads/'):]
+            export_branch(branch, name)
+        if ref.startswith('refs/tags/'):
+            name = ref[len('refs/tags/'):]
+            export_tag(branch, name)
+        parser.next()
+
+    print 'done'
+
+    sys.stdout.flush()
+
+def do_capabilities(parser):
+    print "import"
+    print "refspec refs/heads/*:%s/heads/*" % prefix
+    print
+
+def do_list(parser):
+    global tags
+    print "? refs/heads/%s" % 'master'
+    for tag, revid in parser.repo.tags.get_tag_dict().items():
+        print "? refs/tags/%s" % tag
+        tags[tag] = revid
+    print "@refs/heads/%s HEAD" % 'master'
+    print
+
+def get_repo(url, alias):
+    origin = bzrlib.controldir.ControlDir.open(url)
+    return origin.open_branch()
+
+def main(args):
+    global marks, prefix, dirname
+    global tags, filenodes
+
+    alias = args[1]
+    url = args[2]
+
+    prefix = 'refs/bzr/%s' % alias
+    tags = {}
+    filenodes = {}
+
+    gitdir = os.environ['GIT_DIR']
+    dirname = os.path.join(gitdir, 'bzr', alias)
+
+    if not os.path.exists(dirname):
+        os.makedirs(dirname)
+
+    repo = get_repo(url, alias)
+
+    marks_path = os.path.join(dirname, 'marks-int')
+    marks = Marks(marks_path)
+
+    parser = Parser(repo)
+    for line in parser:
+        if parser.check('capabilities'):
+            do_capabilities(parser)
+        elif parser.check('list'):
+            do_list(parser)
+        elif parser.check('import'):
+            do_import(parser)
+        else:
+            die('unhandled command: %s' % line)
+        sys.stdout.flush()
+
+    marks.store()
+
+sys.exit(main(sys.argv))