tracim_v2/backend/tracim_backend/lib/webdav/dav_provider.py

# coding: utf8

import re
from os.path import basename, dirname

from sqlalchemy.orm.exc import NoResultFound

from tracim_backend import CFG
from tracim_backend.lib.webdav.utils import transform_to_bdd, HistoryType, \
    SpecialFolderExtension
from tracim_backend.models.contents import CONTENT_TYPES

from wsgidav.dav_provider import DAVProvider
from wsgidav.lock_manager import LockManager


from tracim_backend.lib.webdav.lock_storage import LockStorage
from tracim_backend.lib.core.content import ContentApi
from tracim_backend.lib.core.content import ContentRevisionRO
from tracim_backend.lib.core.workspace import WorkspaceApi
from tracim_backend.lib.webdav import resources
from tracim_backend.lib.webdav.utils import normpath
from tracim_backend.models.data import Content
from tracim_backend.models.data import Workspace


class Provider(DAVProvider):
    """
    This class' role is to provide to wsgidav _DAVResource. Wsgidav will then use them to execute action and send
    informations to the client
    """

    def __init__(
            self,
            app_config: CFG,
            show_history=True,
            show_deleted=True,
            show_archived=True,
            manage_locks=True,
    ):
        super(Provider, self).__init__()

        if manage_locks:
            self.lockManager = LockManager(LockStorage())

        self.app_config = app_config
        self._show_archive = show_archived
        self._show_delete = show_deleted
        self._show_history = show_history

    def show_history(self):
        return self._show_history

    def show_delete(self):
        return self._show_delete

    def show_archive(self):
        return self._show_archive

    #########################################################
    # Everything override from DAVProvider
    def getResourceInst(self, path: str, environ: dict):
        """
        Called by wsgidav whenever a request is called to get the _DAVResource corresponding to the path
        """
        user = environ['tracim_user']
        session = environ['tracim_dbsession']
        if not self.exists(path, environ):
            return None
        path = normpath(path)
        root_path = environ['http_authenticator.realm']

        # If the requested path is the root, then we return a RootResource resource
        if path == root_path:
            return resources.RootResource(
                path=path,
                environ=environ,
                user=user,
                session=session
            )

        workspace_api = WorkspaceApi(
            current_user=user,
            session=session,
            config=self.app_config,
        )
        workspace = self.get_workspace_from_path(path, workspace_api)

        # If the request path is in the form root/name, then we return a WorkspaceResource resource
        parent_path = dirname(path)
        if parent_path == root_path:
            if not workspace:
                return None
            return resources.WorkspaceResource(
                path=path,
                environ=environ,
                workspace=workspace,
                user=user,
                session=session,
            )

        # And now we'll work on the path to establish which type or resource is requested

        content_api = ContentApi(
            current_user=user,
            session=session,
            config=self.app_config,
            show_archived=False,  # self._show_archive,
            show_deleted=False,  # self._show_delete
        )

        content = self.get_content_from_path(
            path=path,
            content_api=content_api,
            workspace=workspace
        )


        # Easy cases : path either end with /.deleted, /.archived or /.history, then we return corresponding resources
        if path.endswith(SpecialFolderExtension.Archived) and self._show_archive:
            return resources.ArchivedFolderResource(
                path=path,
                environ=environ,
                workspace=workspace,
                user=user,
                content=content,
                session=session,
            )

        if path.endswith(SpecialFolderExtension.Deleted) and self._show_delete:
            return resources.DeletedFolderResource(
                path=path,
                environ=environ,
                workspace=workspace,
                user=user,
                content=content,
                session=session,
            )

        if path.endswith(SpecialFolderExtension.History) and self._show_history:
            is_deleted_folder = re.search(r'/\.deleted/\.history$', path) is not None
            is_archived_folder = re.search(r'/\.archived/\.history$', path) is not None

            type = HistoryType.Deleted if is_deleted_folder \
                else HistoryType.Archived if is_archived_folder \
                else HistoryType.Standard

            return resources.HistoryFolderResource(
                path=path,
                environ=environ,
                workspace=workspace,
                user=user,
                content=content,
                session=session,
                type=type
            )

        # Now that's more complicated, we're trying to find out if the path end with /.history/file_name
        is_history_file_folder = re.search(r'/\.history/([^/]+)$', path) is not None

        if is_history_file_folder and self._show_history:
            return resources.HistoryFileFolderResource(
                path=path,
                environ=environ,
                user=user,
                content=content,
                session=session,
            )
        # And here next step :
        is_history_file = re.search(r'/\.history/[^/]+/\((\d+) - [a-zA-Z]+\) .+', path) is not None

        if self._show_history and is_history_file:

            revision_id = re.search(r'/\.history/[^/]+/\((\d+) - [a-zA-Z]+\) ([^/].+)$', path).group(1)

            content_revision = content_api.get_one_revision(revision_id)
            content = self.get_content_from_revision(content_revision, content_api)

            if content.type == CONTENT_TYPES.File.slug:
                return resources.HistoryFileResource(
                    path=path,
                    environ=environ,
                    user=user,
                    content=content,
                    content_revision=content_revision,
                    session=session,
                )
            else:
                return resources.HistoryOtherFile(
                    path=path,
                    environ=environ,
                    user=user,
                    content=content,
                    content_revision=content_revision,
                    session=session,
                )

        # And if we're still going, the client is asking for a standard Folder/File/Page/Thread so we check the type7
        # and return the corresponding resource

        if content is None:
            return None
        if content.type == CONTENT_TYPES.Folder.slug:
            return resources.FolderResource(
                path=path,
                environ=environ,
                workspace=content.workspace,
                content=content,
                session=session,
                user=user,
            )
        elif content.type == CONTENT_TYPES.File.slug:
            return resources.FileResource(
                path=path,
                environ=environ,
                content=content,
                session=session,
                user=user
            )
        else:
            return resources.OtherFileResource(
                path=path,
                environ=environ,
                content=content,
                session=session,
                user=user,
            )

    def exists(self, path, environ) -> bool:
        """
        Called by wsgidav to check if a certain path is linked to a _DAVResource
        """

        path = normpath(path)
        working_path = self.reduce_path(path)
        root_path = environ['http_authenticator.realm']
        parent_path = dirname(working_path)
        user = environ['tracim_user']
        session = environ['tracim_dbsession']
        if path == root_path:
            return True

        workspace = self.get_workspace_from_path(
            path,
            WorkspaceApi(
                current_user=user,
                session=session,
                config=self.app_config,
            )
        )

        if parent_path == root_path or workspace is None:
            return workspace is not None

        # TODO bastien: Arnaud avait mis a True, verif le comportement
        # lorsque l'on explore les dossiers archive et deleted
        content_api = ContentApi(
            current_user=user,
            session=session,
            config=self.app_config,
            show_archived=False,
            show_deleted=False
        )

        revision_id = re.search(r'/\.history/[^/]+/\((\d+) - [a-zA-Z]+\) ([^/].+)$', path)

        is_archived = self.is_path_archive(path)

        is_deleted = self.is_path_delete(path)

        if revision_id:
            revision_id = revision_id.group(1)
            content = content_api.get_one_revision(revision_id)
        else:
            content = self.get_content_from_path(working_path, content_api, workspace)

        return content is not None \
            and content.is_deleted == is_deleted \
            and content.is_archived == is_archived

    def is_path_archive(self, path):
        """
        This function will check if a given path is linked to a file that's archived or not. We're checking if the
        given path end with one of these string :

        ex:
            - /a/b/.archived/my_file
            - /a/b/.archived/.history/my_file
            - /a/b/.archived/.history/my_file/(3615 - edition) my_file
        """

        return re.search(
            r'/\.archived/(\.history/)?(?!\.history)[^/]*(/\.)?(history|deleted|archived)?$',
            path
        ) is not None

    def is_path_delete(self, path):
        """
        This function will check if a given path is linked to a file that's deleted or not. We're checking if the
        given path end with one of these string :

        ex:
            - /a/b/.deleted/my_file
            - /a/b/.deleted/.history/my_file
            - /a/b/.deleted/.history/my_file/(3615 - edition) my_file
        """

        return re.search(
            r'/\.deleted/(\.history/)?(?!\.history)[^/]*(/\.)?(history|deleted|archived)?$',
            path
        ) is not None

    def reduce_path(self, path: str) -> str:
        """
        As we use the given path to request the database

        ex: if the path is /a/b/.deleted/c/.archived, we're trying to get the archived content of the 'c' resource,
        we need to keep the path /a/b/c

        ex: if the path is /a/b/.history/my_file, we're trying to get the history of the file my_file, thus we need
        the path /a/b/my_file

        ex: if the path is /a/b/.history/my_file/(1985 - edition) my_old_name, we're looking for,
        thus we remove all useless information
        """
        path = re.sub(r'/\.archived', r'', path)
        path = re.sub(r'/\.deleted', r'', path)
        path = re.sub(r'/\.history/[^/]+/(\d+)-.+', r'/\1', path)
        path = re.sub(r'/\.history/([^/]+)', r'/\1', path)
        path = re.sub(r'/\.history', r'', path)

        return path

    def get_content_from_path(self, path, content_api: ContentApi, workspace: Workspace) -> Content:
        """
        Called whenever we want to get the Content item from the database for a given path
        """
        path = self.reduce_path(path)
        parent_path = dirname(path)

        relative_parents_path = parent_path[len(workspace.label)+1:]
        parents = relative_parents_path.split('/')

        try:
            parents.remove('')
        except ValueError:
            pass
        parents = [transform_to_bdd(x) for x in parents]

        try:
            return content_api.get_one_by_label_and_parent_labels(
                content_label=transform_to_bdd(basename(path)),
                content_parent_labels=parents,
                workspace=workspace,
            )
        except NoResultFound:
            return None

    def get_content_from_revision(self, revision: ContentRevisionRO, api: ContentApi) -> Content:
        try:
            return api.get_one(revision.content_id, CONTENT_TYPES.Any_SLUG)
        except NoResultFound:
            return None

    def get_parent_from_path(self, path, api: ContentApi, workspace) -> Content:
        return self.get_content_from_path(dirname(path), api, workspace)

    def get_workspace_from_path(self, path: str, api: WorkspaceApi) -> Workspace:
        try:
            return api.get_one_by_label(transform_to_bdd(path.split('/')[1]))
        except NoResultFound:
            return None