convert: fetch svn changes on demand (in batches)

hgext/convert/subversion.py

@@ -1,524 +1,527 b''
 # Subversion 1.4/1.5 Python API backend
 #
 # Copyright(C) 2007 Daniel Holth et al
 
 import pprint
 import locale
 
 from mercurial import util
 
 # Subversion stuff. Works best with very recent Python SVN bindings
 # e.g. SVN 1.5 or backports. Thanks to the bzr folks for enhancing
 # these bindings.
 
 from cStringIO import StringIO
 
 from common import NoRepo, commit, converter_source
 
 try:
     from svn.core import SubversionException, Pool
     import svn.core
     import svn.ra
     import svn.delta
     import svn
     import transport
 except ImportError:
     pass
 
 class CompatibilityException(Exception): pass
 
-nbRevisionsPerFetch = 50
+LOG_BATCH_SIZE = 50
 
 class svn_entry(object):
     """Emulate a Subversion path change."""
     __slots__ = ['path', 'copyfrom_path', 'copyfrom_rev', 'action']
     def __init__(self, entry):
         self.copyfrom_path = entry.copyfrom_path
         self.copyfrom_rev = entry.copyfrom_rev
         self.action = entry.action
 
     def __str__(self):
         return "%s %s %s" % (self.action, self.copyfrom_path, self.copyfrom_rev)
 
     def __repr__(self):
         return self.__str__()
 
 class svn_paths(object):
     """Emulate a Subversion ordered dictionary of changed paths."""
     __slots__ = ['values', 'order']
     def __init__(self, orig_paths):
         self.order = []
         self.values = {}
         if hasattr(orig_paths, 'keys'):
             self.order = sorted(orig_paths.keys())
             self.values.update(orig_paths)
             return
         if not orig_paths:
             return
         for path in orig_paths:
             self.order.append(path)
             self.values[path] = svn_entry(orig_paths[path])
         self.order.sort() # maybe the order it came in isn't so great...
 
     def __iter__(self):
         return iter(self.order)
 
     def __getitem__(self, key):
         return self.values[key]
 
     def __str__(self):
         s = "{\n"
         for path in self.order:
             s += "'%s': %s,\n" % (path, self.values[path])
         s += "}"
         return s
     
     def __repr__(self):
         return self.__str__()
 
 # SVN conversion code stolen from bzr-svn and tailor
 class convert_svn(converter_source):
     def __init__(self, ui, url, rev=None):
         try:
             SubversionException
         except NameError:
             msg = 'subversion python bindings could not be loaded\n'
             ui.warn(msg)
             raise NoRepo(msg)
 
         self.ui = ui
         self.encoding = locale.getpreferredencoding()
         latest = None
         if rev:
             try:
                 latest = int(rev)
             except ValueError:
                 raise util.Abort('svn: revision %s is not an integer' % rev)
         try:
             # Support file://path@rev syntax. Useful e.g. to convert
             # deleted branches.
             url, latest = url.rsplit("@", 1)
             latest = int(latest)
         except ValueError, e:
             pass
         self.url = url
         self.encoding = 'UTF-8' # Subversion is always nominal UTF-8
         try:
             self.transport = transport.SvnRaTransport(url = url)
             self.ra = self.transport.ra
             self.base = svn.ra.get_repos_root(self.ra)
             self.module = self.url[len(self.base):]
             self.modulemap = {} # revision, module
             self.commits = {}
             self.files = {}
             self.uuid = svn.ra.get_uuid(self.ra).decode(self.encoding)
         except SubversionException, e:
             raise NoRepo("couldn't open SVN repo %s" % url)
 
         try:
             self.get_blacklist()
         except IOError, e:
             pass
 
         if not latest:
             latest = svn.ra.get_latest_revnum(self.ra)
         dirent = svn.ra.stat(self.ra, self.module, latest)
         self.last_changed = dirent.created_rev
 
         self.head = self.rev(self.last_changed)
 
-        # Should lazily fetch revisions in batches of, say, 1,000...:
-        self._fetch_revisions(from_revnum=self.last_changed, to_revnum=0)
-
     def rev(self, revnum):
         return (u"svn:%s%s@%s" % (self.uuid, self.module, revnum)).decode(self.encoding)
             
     def get_blacklist(self):
         """Avoid certain revision numbers.
         It is not uncommon for two nearby revisions to cancel each other
         out, e.g. 'I copied trunk into a subdirectory of itself instead
         of making a branch'. The converted repository is significantly
         smaller if we ignore such revisions."""
         self.blacklist = set()
         blacklist = self.blacklist
         for line in file("blacklist.txt", "r"):
             if not line.startswith("#"):
                 try:
                     svn_rev = int(line.strip())
                     blacklist.add(svn_rev)
                 except ValueError, e:
                     pass # not an integer or a comment
 
     def is_blacklisted(self, svn_rev):
         return svn_rev in self.blacklist
 
     def reparent(self, module):
         svn_url = self.base + module
         self.ui.debug("reparent to %s\n" % svn_url.encode(self.encoding))
         svn.ra.reparent(self.ra, svn_url.encode(self.encoding))
 
     def _fetch_revisions(self, from_revnum = 0, to_revnum = 347, pb=None):
-        self.parent_cset = None
-        self.child_cset = None
-        
+        if not hasattr(self, 'child_rev'):
+            self.child_rev = from_revnum
+            self.child_cset = self.commits.get(self.child_rev)
+        else:
+            self.commits[self.child_rev] = self.child_cset
+
         self.ui.debug('Fetching revisions %d to %d\n' % (from_revnum, to_revnum))
 
         def get_entry_from_path(path, module=self.module):
             # Given the repository url of this wc, say
             #   "http://server/plone/CMFPlone/branches/Plone-2_0-branch"
             # extract the "entry" portion (a relative path) from what
             # svn log --xml says, ie
             #   "/CMFPlone/branches/Plone-2_0-branch/tests/PloneTestCase.py"
             # that is to say "tests/PloneTestCase.py"
 
             if path.startswith(module):
                 relative = path[len(module):]
                 if relative.startswith('/'):
                     return relative[1:]
                 else:
                     return relative
 
             # The path is outside our tracked tree...
             self.ui.debug('Ignoring %r since it is not under %r\n' % (path, module))
             return None
 
         received = []
         def rcvr(*arg, **args):
             orig_paths, revnum, author, date, message, pool = arg
             new_orig_paths = svn_paths(orig_paths)
             rcvr2(new_orig_paths, revnum, author, date, message, pool)
 
         def rcvr2(orig_paths, revnum, author, date, message, pool, better_paths = None):
             if not self.is_blacklisted(revnum):
                 received.append((orig_paths, revnum, author, date, message))
            
         def after_received(orig_paths, revnum, author, date, message):
             if revnum in self.modulemap:
                 new_module = self.modulemap[revnum]
                 if new_module != self.module:
                     self.module = new_module
                     self.reparent(self.module)
 
             copyfrom = {} # Map of entrypath, revision for finding source of deleted revisions.
             copies = {}
             entries = []
             self.ui.debug("Parsing revision %d\n" % revnum)
             if orig_paths is not None:
                 rev = self.rev(revnum)
                 try:
                     branch = self.module.split("/")[-1]
                     if branch == 'trunk':
                         branch = ''
                 except IndexError:
                     branch = None
                 
                 for path in orig_paths:
                     # self.ui.write("path %s\n" % path)
                     if path == self.module: # Follow branching back in history
                         ent = orig_paths[path]
                         if ent:
                             if ent.copyfrom_path:
                                 self.modulemap[ent.copyfrom_rev] = ent.copyfrom_path
                             else:
                                 self.ui.debug("No copyfrom path, don't know what to do.\n")
                                 # Maybe it was added and there is no more history.
                     entrypath = get_entry_from_path(path, module=self.module)
                     # self.ui.write("entrypath %s\n" % entrypath)
                     if not entrypath:
                         # Outside our area of interest
                         self.ui.debug("boring@%s: %s\n" % (revnum, path))
                         continue
                     entry = entrypath.decode(self.encoding)
                     ent = orig_paths[path]
 
                     kind = svn.ra.check_path(self.ra, entrypath, revnum)
                     if kind == svn.core.svn_node_file:
                         if ent.copyfrom_path:
                             copyfrom_path = get_entry_from_path(ent.copyfrom_path)
                             if copyfrom_path:
                                 self.ui.debug("Copied to %s from %s@%s\n" % (entry, copyfrom_path, ent.copyfrom_rev))
                                 # It's probably important for hg that the source
                                 # exists in the revision's parent, not just the
                                 # ent.copyfrom_rev
                                 fromkind = svn.ra.check_path(self.ra, copyfrom_path, ent.copyfrom_rev)
                                 if fromkind != 0:
                                     copies[self.recode(entry)] = self.recode(copyfrom_path)
                         entries.append(self.recode(entry))
                     elif kind == 0: # gone, but had better be a deleted *file*
                         self.ui.debug("gone from %s\n" % ent.copyfrom_rev)
 
                         fromrev = revnum - 1
                         # might always need to be revnum - 1 in these 3 lines?
                         old_module = self.modulemap.get(fromrev, self.module)
                         basepath = old_module + "/" + get_entry_from_path(path, module=self.module)
                         entrypath = old_module + "/" + get_entry_from_path(path, module=self.module)
 
                         def lookup_parts(p):
                             rc = None
                             parts = p.split("/")
                             for i in range(len(parts)):
                                 part = "/".join(parts[:i])
                                 info = part, copyfrom.get(part, None)
                                 if info[1] is not None:
                                     self.ui.debug("Found parent directory %s\n" % info)
                                     rc = info
                             return rc
 
                         self.ui.debug("base, entry %s %s\n" % (basepath, entrypath))
 
                         frompath, froment = lookup_parts(entrypath) or (None, revnum - 1)
 
                         # need to remove fragment from lookup_parts and replace with copyfrom_path
                         if frompath is not None:
                             self.ui.debug("munge-o-matic\n")
                             self.ui.debug(entrypath + '\n')
                             self.ui.debug(entrypath[len(frompath):] + '\n')
                             entrypath = froment.copyfrom_path + entrypath[len(frompath):]
                             fromrev = froment.copyfrom_rev
                             self.ui.debug("Info: %s %s %s %s\n" % (frompath, froment, ent, entrypath))
 
                         fromkind = svn.ra.check_path(self.ra, entrypath, fromrev)
                         if fromkind == svn.core.svn_node_file:   # a deleted file
                             entries.append(self.recode(entry))
                         else:
                             # print "Deleted/moved non-file:", revnum, path, ent
                             # children = self._find_children(path, revnum - 1)
                             # print "find children %s@%d from %d action %s" % (path, revnum, ent.copyfrom_rev, ent.action)
                             # Sometimes this is tricky. For example: in
                             # The Subversion Repository revision 6940 a dir
                             # was copied and one of its files was deleted 
                             # from the new location in the same commit. This
                             # code can't deal with that yet.
                             if ent.action == 'C':
                                 children = self._find_children(path, fromrev)
                             else:
                                 oroot = entrypath.strip('/')
                                 nroot = path.strip('/')
                                 children = self._find_children(oroot, fromrev)
                                 children = [s.replace(oroot,nroot) for s in children]
                             # Mark all [files, not directories] as deleted.
                             for child in children:
                                 # Can we move a child directory and its
                                 # parent in the same commit? (probably can). Could
                                 # cause problems if instead of revnum -1, 
                                 # we have to look in (copyfrom_path, revnum - 1)
                                 entrypath = get_entry_from_path("/" + child, module=old_module)
                                 if entrypath:
                                     entry = self.recode(entrypath.decode(self.encoding))
                                     if entry in copies:
                                         # deleted file within a copy
                                         del copies[entry]
                                     else:
                                         entries.append(entry)
                     elif kind == svn.core.svn_node_dir:
                         # Should probably synthesize normal file entries
                         # and handle as above to clean up copy/rename handling.
 
                         # If the directory just had a prop change,
                         # then we shouldn't need to look for its children.
                         # Also this could create duplicate entries. Not sure
                         # whether this will matter. Maybe should make entries a set.
                         # print "Changed directory", revnum, path, ent.action, ent.copyfrom_path, ent.copyfrom_rev
                         # This will fail if a directory was copied
                         # from another branch and then some of its files
                         # were deleted in the same transaction.
                         children = self._find_children(path, revnum)
                         children.sort()
                         for child in children:
                             # Can we move a child directory and its
                             # parent in the same commit? (probably can). Could
                             # cause problems if instead of revnum -1, 
                             # we have to look in (copyfrom_path, revnum - 1)
                             entrypath = get_entry_from_path("/" + child, module=self.module)
                             # print child, self.module, entrypath
                             if entrypath:
                                 # Need to filter out directories here...
                                 kind = svn.ra.check_path(self.ra, entrypath, revnum)
                                 if kind != svn.core.svn_node_dir:
                                     entries.append(self.recode(entrypath))
 
                         # Copies here (must copy all from source)
                         # Probably not a real problem for us if
                         # source does not exist
 
                         # Can do this with the copy command "hg copy"
                         # if ent.copyfrom_path:
                         #     copyfrom_entry = get_entry_from_path(ent.copyfrom_path.decode(self.encoding),
                         #             module=self.module)
                         #     copyto_entry = entrypath
                         #
                         #     print "copy directory", copyfrom_entry, 'to', copyto_entry
                         #
                         #     copies.append((copyfrom_entry, copyto_entry))
                         
                         if ent.copyfrom_path:
                             copyfrom_path = ent.copyfrom_path.decode(self.encoding)
                             copyfrom_entry = get_entry_from_path(copyfrom_path, module=self.module)
                             if copyfrom_entry:
                                 copyfrom[path] = ent
                                 self.ui.debug("mark %s came from %s\n" % (path, copyfrom[path]))
 
                                 # Good, /probably/ a regular copy. Really should check
                                 # to see whether the parent revision actually contains
                                 # the directory in question.
                                 children = self._find_children(self.recode(copyfrom_path), ent.copyfrom_rev)
                                 children.sort()
                                 for child in children:
                                     entrypath = get_entry_from_path("/" + child, module=self.module)
                                     if entrypath:
                                         entry = entrypath.decode(self.encoding)
                                         # print "COPY COPY From", copyfrom_entry, entry
                                         copyto_path = path + entry[len(copyfrom_entry):]
                                         copyto_entry =  get_entry_from_path(copyto_path, module=self.module)
                                         # print "COPY", entry, "COPY To", copyto_entry
                                         copies[self.recode(copyto_entry)] = self.recode(entry)
                                         # copy from quux splort/quuxfile
               
                 self.modulemap[revnum] = self.module # track backwards in time
                 # a list of (filename, id) where id lets us retrieve the file.
                 # eg in git, id is the object hash. for svn it'll be the 
                 self.files[rev] = zip(entries, [rev] * len(entries))
 
                 # Example SVN datetime. Includes microseconds.
                 # ISO-8601 conformant
                 # '2007-01-04T17:35:00.902377Z'
                 date = util.parsedate(date[:18] + " UTC", ["%Y-%m-%dT%H:%M:%S"])
 
                 log = message and self.recode(message)
                 author = author and self.recode(author) or ''
 
                 cset = commit(author=author,
-                        date=util.datestr(date), 
-                        desc=log, 
-                        parents=[],
-                        copies=copies,
-                        branch=branch)
+                              date=util.datestr(date), 
+                              desc=log, 
+                              parents=[],
+                              copies=copies,
+                              branch=branch)
 
-                if self.child_cset is not None:
+                if self.child_cset and self.child_rev != rev:
                     self.child_cset.parents = [rev]
-
+                    self.commits[self.child_rev] = self.child_cset
                 self.child_cset = cset
-
-                self.commits[rev] = cset
+                self.child_rev = rev
 
         try:
             discover_changed_paths = True
             strict_node_history = False
             svn.ra.get_log(self.ra, [self.module], from_revnum, to_revnum, 
                            0, discover_changed_paths, strict_node_history, rcvr)
             for args in received:
                 after_received(*args)
             self.last_revnum = to_revnum
         except SubversionException, (_, num):
             if num == svn.core.SVN_ERR_FS_NO_SUCH_REVISION:
                 raise NoSuchRevision(branch=self, 
                     revision="Revision number %d" % to_revnum)
             raise
 
     def getheads(self):
         # svn-url@rev
         # Not safe if someone committed:
         self.heads = [self.head]
         # print self.commits.keys()
         return self.heads
 
     def _getfile(self, file, rev):
         io = StringIO()
         # TODO: ra.get_file transmits the whole file instead of diffs.
         mode = ''
         try:
             revnum = int(rev.split("@")[-1])
             if self.module != self.modulemap[revnum]:
                 self.module = self.modulemap[revnum]
                 self.reparent(self.module)
             info = svn.ra.get_file(self.ra, file, revnum, io)
             if isinstance(info, list):
                 info = info[-1]
             mode = ("svn:executable" in info) and 'x' or ''
             mode = ("svn:special" in info) and 'l' or mode
         except SubversionException, e:
             notfound = (svn.core.SVN_ERR_FS_NOT_FOUND,
                 svn.core.SVN_ERR_RA_DAV_PATH_NOT_FOUND)
             if e.apr_err in notfound: # File not found
                 raise IOError()
             raise
         data = io.getvalue()
         if mode == 'l':
             link_prefix = "link "
             if data.startswith(link_prefix):
                 data = data[len(link_prefix):]
         return data, mode
 
     def getfile(self, file, rev):
         data, mode = self._getfile(file, rev)
         self.modecache[(file, rev)] = mode
         return data
 
     def getmode(self, file, rev):        
         return self.modecache[(file, rev)]
 
     def getchanges(self, rev):
         self.modecache = {}
         files = self.files[rev]
         cl = files
         cl.sort()
         return cl
 
     def getcommit(self, rev):
+        if rev not in self.commits:
+            revnum = int(rev.split('@')[-1])
+            minrev = revnum - LOG_BATCH_SIZE > 0 and revnum - LOG_BATCH_SIZE or 0
+            self._fetch_revisions(from_revnum=revnum, to_revnum=minrev)
         return self.commits[rev]
 
     def gettags(self):
         return []
 
     def _find_children(self, path, revnum):
         path = path.strip("/")
 
         def _find_children_fallback(path, revnum):
             # SWIG python bindings for getdir are broken up to at least 1.4.3
             if not hasattr(self, 'client_ctx'):
                 self.client_ctx = svn.client.create_context()
             optrev = svn.core.svn_opt_revision_t()
             optrev.kind = svn.core.svn_opt_revision_number
             optrev.value.number = revnum
             rpath = '/'.join([self.base, path]).strip('/')
             return ['%s/%s' % (path, x) for x in svn.client.ls(rpath, optrev, True, self.client_ctx).keys()]
 
         if hasattr(self, '_find_children_fallback'):
             return _find_children_fallback(path, revnum)
 
         self.reparent("/" + path)
         pool = Pool()
 
         children = []
         def find_children_inner(children, path, revnum = revnum):
             if hasattr(svn.ra, 'get_dir2'): # Since SVN 1.4
                 fields = 0xffffffff # Binding does not provide SVN_DIRENT_ALL
                 getdir = svn.ra.get_dir2(self.ra, path, revnum, fields, pool)
             else:
                 getdir = svn.ra.get_dir(self.ra, path, revnum, pool)
             if type(getdir) == dict:
                 # python binding for getdir is broken up to at least 1.4.3
                 raise CompatibilityException()
             dirents = getdir[0]
             if type(dirents) == int:
                 # got here once due to infinite recursion bug
                 # pprint.pprint(getdir)
                 return
             c = dirents.keys()
             c.sort()
             for child in c:
                 dirent = dirents[child]
                 if dirent.kind == svn.core.svn_node_dir:
                     find_children_inner(children, (path + "/" + child).strip("/"))
                 else:
                     children.append((path + "/" + child).strip("/"))
 
         try:
             find_children_inner(children, "")
         except CompatibilityException:
             self._find_children_fallback = True
             self.reparent(self.module)
             return _find_children_fallback(path, revnum)
 
         self.reparent(self.module)
         return [path + "/" + c for c in children]