if hasattr(self, '_mimetype'):

            if (isinstance(self._mimetype, (tuple, list,)) and

                len(self._mimetype) == 2):

                return self._mimetype

            else:

                raise NodeError('given _mimetype attribute must be an 2 '

                               'element list or tuple')

        mtype, encoding = mimetypes.guess_type(self.name)

        if mtype is None:

            if self.is_binary:

                mtype = 'application/octet-stream'

                encoding = None

            else:

                mtype = 'text/plain'

                encoding = None

        return mtype, encoding

    @LazyProperty

    def mimetype(self):

        """

        Wrapper around full mimetype info. It returns only type of fetched

        mimetype without the encoding part. use get_mimetype function to fetch

        full set of (type,encoding)

        """

        return self.get_mimetype()[0]

    @LazyProperty

    def mimetype_main(self):

        return self.mimetype.split('/')[0]

    @LazyProperty

    def lexer(self):

        """

        Returns pygment's lexer class. Would try to guess lexer taking file's

        content, name and mimetype.

        """

        try:

            lexer = lexers.guess_lexer_for_filename(self.name, self.content, stripnl=False)

        except lexers.ClassNotFound:

            lexer = lexers.TextLexer(stripnl=False)

        # returns first alias

        return lexer

    @LazyProperty

    def lexer_alias(self):

        """

        Returns first alias of the lexer guessed for this file.

        """

        return self.lexer.aliases[0]

    @LazyProperty

    def history(self):

        """

        Returns a list of changeset for this file in which the file was changed

        """

        if self.changeset is None:

            raise NodeError('Unable to get changeset for this FileNode')

        return self.changeset.get_file_history(self.path)

    @LazyProperty

    def annotate(self):

        """

        Returns a list of three element tuples with lineno,changeset and line

        """

        if self.changeset is None:

            raise NodeError('Unable to get changeset for this FileNode')

        return self.changeset.get_file_annotate(self.path)

    @LazyProperty

    def state(self):

        if not self.changeset:

            raise NodeError("Cannot check state of the node if it's not "

                "linked with changeset")

        elif self.path in (node.path for node in self.changeset.added):

            return NodeState.ADDED

        elif self.path in (node.path for node in self.changeset.changed):

            return NodeState.CHANGED

        else:

            return NodeState.NOT_CHANGED

    @property

    def is_binary(self):

        """

        Returns True if file has binary content.

        """

        _bin = '\0' in self._get_content()

        return _bin

    @LazyProperty

    def extension(self):

        """Returns filenode extension"""

        return self.name.split('.')[-1]

    def is_executable(self):

        """

        Returns ``True`` if file has executable flag turned on.

        """

        return bool(self.mode & stat.S_IXUSR)

    def __repr__(self):

        return '<%s %r @ %s>' % (self.__class__.__name__, self.path,

                                 getattr(self.changeset, 'short_id', ''))

class RemovedFileNode(FileNode):

    """

    Dummy FileNode class - trying to access any public attribute except path,

    name, kind or state (or methods/attributes checking those two) would raise

    RemovedFileNodeError.

    """

    ALLOWED_ATTRIBUTES = [

        'name', 'path', 'state', 'is_root', 'is_file', 'is_dir', 'kind',

        'added', 'changed', 'not_changed', 'removed'

    ]

    def __init__(self, path):

        """

        :param path: relative path to the node

        """

        super(RemovedFileNode, self).__init__(path=path)

    def __getattribute__(self, attr):

        if attr.startswith('_') or attr in RemovedFileNode.ALLOWED_ATTRIBUTES:

            return super(RemovedFileNode, self).__getattribute__(attr)

        raise RemovedFileNodeError("Cannot access attribute %s on "

            "RemovedFileNode" % attr)

    @LazyProperty

    def state(self):

        return NodeState.REMOVED

class DirNode(Node):

    """

    DirNode stores list of files and directories within this node.

    Nodes may be used standalone but within repository context they

    lazily fetch data within same repositorty's changeset.

    """

    def __init__(self, path, nodes=(), changeset=None):

        """

        Only one of ``nodes`` and ``changeset`` may be given. Passing both

        would raise ``NodeError`` exception.

        :param path: relative path to the node

        :param nodes: content may be passed to constructor

        :param changeset: if given, will use it to lazily fetch content

        :param size: always 0 for ``DirNode``

        """

        if nodes and changeset:

            raise NodeError("Cannot use both nodes and changeset")

        super(DirNode, self).__init__(path, NodeKind.DIR)

        self.changeset = changeset

        self._nodes = nodes

    @LazyProperty

    def content(self):

        raise NodeError("%s represents a dir and has no ``content`` attribute"

            % self)

    @LazyProperty

    def nodes(self):

        if self.changeset:

            nodes = self.changeset.get_nodes(self.path)

        else:

            nodes = self._nodes

        self._nodes_dict = dict((node.path, node) for node in nodes)

        return sorted(nodes)

    @LazyProperty

    def files(self):

        return sorted((node for node in self.nodes if node.is_file()))

    @LazyProperty

    def dirs(self):

        return sorted((node for node in self.nodes if node.is_dir()))

    def __iter__(self):

        for node in self.nodes:

            yield node

    def get_node(self, path):

        """

        Returns node from within this particular ``DirNode``, so it is now

        allowed to fetch, i.e. node located at 'docs/api/index.rst' from node

        'docs'. In order to access deeper nodes one must fetch nodes between

        them first - this would work::

           docs = root.get_node('docs')

        self.sa.add(repo)

        return repo

    def _handle_rc_scm_extras(self, username, repo_name, repo_alias):

        from rhodecode import CONFIG

        from rhodecode.lib.base import _get_ip_addr

        try:

            from pylons import request

            environ = request.environ

        except TypeError:

            # we might use this outside of request context, let's fake the

            # environ data

            from webob import Request

            environ = Request.blank('').environ

        extras = {

            'ip': _get_ip_addr(environ),

            'username': username,

            'action': 'push_local',

            'repository': repo_name,

            'scm': repo_alias,

            'config': CONFIG['__file__'],

            'server_url': get_server_url(environ),

            'make_lock': None,

            'locked_by': [None, None]

        }

        _set_extras(extras)

    def _handle_push(self, repo, username, action, repo_name, revisions):

        """

        Triggers push action hooks

        :param repo: SCM repo

        :param username: username who pushes

        :param action: push/push_loca/push_remote

        :param repo_name: name of repo

        :param revisions: list of revisions that we pushed

        """

        self._handle_rc_scm_extras(username, repo_name, repo_alias=repo.alias)

        _scm_repo = repo._repo

        # trigger push hook

        if repo.alias == 'hg':

            log_push_action(_scm_repo.ui, _scm_repo, node=revisions[0])

        elif repo.alias == 'git':

            log_push_action(None, _scm_repo, _git_revs=revisions)

    def _get_IMC_module(self, scm_type):

        """

        Returns InMemoryCommit class based on scm_type

        :param scm_type:

        """

        if scm_type == 'hg':

            from rhodecode.lib.vcs.backends.hg import \

                MercurialInMemoryChangeset as IMC

        elif scm_type == 'git':

            from rhodecode.lib.vcs.backends.git import \

                GitInMemoryChangeset as IMC

        return IMC

    def pull_changes(self, repo, username):

        dbrepo = self.__get_repo(repo)

        clone_uri = dbrepo.clone_uri

        if not clone_uri:

            raise Exception("This repository doesn't have a clone uri")

        repo = dbrepo.scm_instance

        repo_name = dbrepo.repo_name

        try:

            if repo.alias == 'git':

                repo.fetch(clone_uri)

            else:

                repo.pull(clone_uri)

            self.mark_for_invalidation(repo_name)

        except Exception:

            log.error(traceback.format_exc())

            raise

    def commit_change(self, repo, repo_name, cs, user, author, message,

                      content, f_path):

        """

        Commits changes

        :param repo: SCM instance

        """

        user = self._get_user(user)

        IMC = self._get_IMC_module(repo.alias)

        # decoding here will force that we have proper encoded values

        # in any other case this will throw exceptions and deny commit

        content = safe_str(content)

        path = safe_str(f_path)

        # message and author needs to be unicode

        # proper backend should then translate that into required type

        message = safe_unicode(message)

        author = safe_unicode(author)

                       author=author,

                       parents=[cs], branch=cs.branch)

        self.mark_for_invalidation(repo_name)

        self._handle_push(repo,

                          username=user.username,

                          action='push_local',

                          repo_name=repo_name,

                          revisions=[tip.raw_id])

        return tip

    def create_node(self, repo, repo_name, cs, user, author, message, content,

                      f_path):

        user = self._get_user(user)

        IMC = self._get_IMC_module(repo.alias)

        # decoding here will force that we have proper encoded values

        # in any other case this will throw exceptions and deny commit

        if isinstance(content, (basestring,)):

            content = safe_str(content)

        elif isinstance(content, (file, cStringIO.OutputType,)):

            content = content.read()

        else:

            raise Exception('Content is of unrecognized type %s' % (

                type(content)

            ))

        message = safe_unicode(message)

        author = safe_unicode(author)

        path = safe_str(f_path)

        m = IMC(repo)

        if isinstance(cs, EmptyChangeset):

            # EmptyChangeset means we we're editing empty repository

            parents = None

        else:

            parents = [cs]

        m.add(FileNode(path, content=content))

        tip = m.commit(message=message,

                       author=author,

                       parents=parents, branch=cs.branch)

        self.mark_for_invalidation(repo_name)

        self._handle_push(repo,

                          username=user.username,

                          action='push_local',

                          repo_name=repo_name,

                          revisions=[tip.raw_id])

        return tip

    def get_nodes(self, repo_name, revision, root_path='/', flat=True):

        """

        recursive walk in root dir and return a set of all path in that dir

        based on repository walk function

        :param repo_name: name of repository

        :param revision: revision for which to list nodes

        :param root_path: root path to list

        :param flat: return as a list, if False returns a dict with decription

        """

        _files = list()

        _dirs = list()

        try:

            _repo = self.__get_repo(repo_name)

            changeset = _repo.scm_instance.get_changeset(revision)

            root_path = root_path.lstrip('/')

            for topnode, dirs, files in changeset.walk(root_path):

                for f in files:

                    _files.append(f.path if flat else {"name": f.path,

                                                       "type": "file"})

                for d in dirs:

                    _dirs.append(d.path if flat else {"name": d.path,

                                                      "type": "dir"})

        except RepositoryError:

            log.debug(traceback.format_exc())

            raise

        return _dirs, _files

    def get_unread_journal(self):

        return self.sa.query(UserLog).count()

    def get_repo_landing_revs(self, repo=None):

        """

        Generates select option with tags branches and bookmarks (for hg only)

        grouped by type

        :param repo:

        :type repo:

        """

        hist_l = []

        choices = []

        repo = self.__get_repo(repo)