--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/web/server/utils.py	Fri Jun 02 16:49:28 2023 +0200
@@ -0,0 +1,115 @@
+#!/usr/bin/env python3
+
+
+# Libervia: a Salut à Toi frontend
+# Copyright (C) 2011-2021 Jérôme Poisson <goffi@goffi.org>
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+from libervia.backend.core.i18n import _
+from twisted.internet import reactor
+from twisted.internet import defer
+from libervia.backend.core import exceptions
+from libervia.backend.core.log import getLogger
+import urllib.request, urllib.parse, urllib.error
+
+log = getLogger(__name__)
+
+
+def quote(value, safe="@"):
+    """shortcut to quote an unicode value for URL"""
+    return urllib.parse.quote(value, safe=safe)
+
+
+class ProgressHandler(object):
+    """class to help the management of progressions"""
+
+    handlers = {}
+
+    def __init__(self, host, progress_id, profile):
+        self.host = host
+        self.progress_id = progress_id
+        self.profile = profile
+
+    @classmethod
+    def _signal(cls, name, progress_id, data, profile):
+        handlers = cls.handlers
+        if profile in handlers and progress_id in handlers[profile]:
+            handler_data = handlers[profile][progress_id]
+            timeout = handler_data["timeout"]
+            if timeout.active():
+                timeout.cancel()
+            cb = handler_data[name]
+            if cb is not None:
+                cb(data)
+            if name == "started":
+                pass
+            elif name == "finished":
+                handler_data["deferred"].callback(data)
+                handler_data["instance"].unregister_handler()
+            elif name == "error":
+                handler_data["deferred"].errback(Exception(data))
+                handler_data["instance"].unregister_handler()
+            else:
+                log.error("unexpected signal: {name}".format(name=name))
+
+    def _timeout(self):
+        log.warning(
+            _(
+                "No progress received, cancelling handler: {progress_id} [{profile}]"
+            ).format(progress_id=self.progress_id, profile=self.profile)
+        )
+
+    def unregister_handler(self):
+        """remove a previously registered handler"""
+        try:
+            del self.handlers[self.profile][self.progress_id]
+        except KeyError:
+            log.warning(
+                _("Trying to remove unknown handler: {progress_id} [{profile}]").format(
+                    progress_id=self.progress_id, profile=self.profile
+                )
+            )
+        else:
+            if not self.handlers[self.profile]:
+                self.handlers[self.profile]
+
+    def register(self, started_cb=None, finished_cb=None, error_cb=None, timeout=30):
+        """register the signals to handle progression
+
+        @param started_cb(callable, None): method to call when progress_started signal is received
+        @param finished_cb(callable, None): method to call when progress_finished signal is received
+        @param error_cb(callable, None): method to call when progress_error signal is received
+        @param timeout(int): progress time out
+            if nothing happen in this progression during this delay,
+            an exception is raised
+        @return (D(dict[unicode,unicode])): a deferred called when progression is finished
+        """
+        handler_data = self.handlers.setdefault(self.profile, {}).setdefault(
+            self.progress_id, {}
+        )
+        if handler_data:
+            raise exceptions.ConflictError(
+                "There is already one handler for this progression"
+            )
+        handler_data["instance"] = self
+        deferred = handler_data["deferred"] = defer.Deferred()
+        handler_data["started"] = started_cb
+        handler_data["finished"] = finished_cb
+        handler_data["error"] = error_cb
+        handler_data["timeout"] = reactor.callLater(timeout, self._timeout)
+        return deferred
+
+
+class SubPage(str):
+    """use to mark subpages when generating a page path"""