--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/backend/plugins/plugin_xep_0103.py	Fri Jun 02 11:49:51 2023 +0200
@@ -0,0 +1,90 @@
+#!/usr/bin/env python3
+
+# Copyright (C) 2009-2022 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 typing import Dict, Any
+
+from twisted.words.xish import domish
+
+from libervia.backend.core.constants import Const as C
+from libervia.backend.core.i18n import _
+from libervia.backend.core.log import getLogger
+from libervia.backend.core import exceptions
+
+log = getLogger(__name__)
+
+
+PLUGIN_INFO = {
+    C.PI_NAME: "URL Address Information",
+    C.PI_IMPORT_NAME: "XEP-0103",
+    C.PI_TYPE: "XEP",
+    C.PI_MODES: C.PLUG_MODE_BOTH,
+    C.PI_PROTOCOLS: ["XEP-0103"],
+    C.PI_MAIN: "XEP_0103",
+    C.PI_HANDLER: "no",
+    C.PI_DESCRIPTION: _("""Implementation of XEP-0103 (URL Address Information)"""),
+}
+
+NS_URL_DATA = "http://jabber.org/protocol/url-data"
+
+
+class XEP_0103:
+    namespace = NS_URL_DATA
+
+    def __init__(self, host):
+        log.info(_("XEP-0103 (URL Address Information) plugin initialization"))
+        host.register_namespace("url-data", NS_URL_DATA)
+
+    def get_url_data_elt(
+        self,
+        url: str,
+        **kwargs
+    ) -> domish.Element:
+        """Generate the element describing the URL
+
+        @param url: URL to use
+        @param extra: extra metadata describing how to access the URL
+        @return: ``<url-data/>`` element
+        """
+        url_data_elt = domish.Element((NS_URL_DATA, "url-data"))
+        url_data_elt["target"] = url
+        return url_data_elt
+
+    def parse_url_data_elt(
+        self,
+        url_data_elt: domish.Element
+    ) -> Dict[str, Any]:
+        """Parse <url-data/> element
+
+        @param url_data_elt: <url-data/> element
+            a parent element can also be used
+        @return: url-data data. It's a dict whose keys correspond to
+            [get_url_data_elt] parameters
+        @raise exceptions.NotFound: no <url-data/> element has been found
+        """
+        if url_data_elt.name != "url-data":
+            try:
+                url_data_elt = next(
+                    url_data_elt.elements(NS_URL_DATA, "url-data")
+                )
+            except StopIteration:
+                raise exceptions.NotFound
+        try:
+            data: Dict[str, Any] = {"url": url_data_elt["target"]}
+        except KeyError:
+            raise ValueError(f'"target" attribute is missing: {url_data_elt.toXml}')
+
+        return data