Add XEP-0100 (Gateway Interaction) plugin

Remove usused prompt_future attribute

Add plugin_end

Update with mathieui's comments

Add option to transfer messages from unregistered users

XEP 0100 plugin

3 files changed, 264 insertions, 0 deletions

diff --git a/slixmpp/plugins/__init__.py b/slixmpp/plugins/__init__.py
index 70ec55d2..d087f92b 100644
--- a/slixmpp/plugins/__init__.py
+++ b/slixmpp/plugins/__init__.py
@@ -42,6 +42,7 @@ __all__ = [
     'xep_0092',  # Software Version
 #   'xep_0095',  # Legacy Stream Initiation. Don’t automatically load
 #   'xep_0096',  # Legacy SI File Transfer. Don’t automatically load
+    'xep_0100',  # Gateway interaction
     'xep_0106',  # JID Escaping
     'xep_0107',  # User Mood
     'xep_0108',  # User Activity
diff --git a/slixmpp/plugins/xep_0100/__init__.py b/slixmpp/plugins/xep_0100/__init__.py
new file mode 100644
index 00000000..101b8db0
--- /dev/null
+++ b/slixmpp/plugins/xep_0100/__init__.py
@@ -0,0 +1,6 @@
+from slixmpp.plugins.base import register_plugin
+
+from slixmpp.plugins.xep_0100.gateway import XEP_0100, LegacyError
+
+
+register_plugin(XEP_0100)
diff --git a/slixmpp/plugins/xep_0100/gateway.py b/slixmpp/plugins/xep_0100/gateway.py
new file mode 100644
index 00000000..8ff102bb
--- /dev/null
+++ b/slixmpp/plugins/xep_0100/gateway.py
@@ -0,0 +1,257 @@
+import asyncio
+import logging
+from functools import partial
+import typing
+
+from slixmpp import Message, Iq, Presence, JID
+from slixmpp.xmlstream.handler import Callback
+from slixmpp.xmlstream.matcher import StanzaPath
+from slixmpp.plugins import BasePlugin
+
+
+class XEP_0100(BasePlugin):
+
+    """
+    XEP-0100: Gateway interaction
+
+    Does not cover the deprecated Agent Information and 'jabber:iq:gateway' protocols
+
+    Events registered by this plugin:
+
+    - legacy_login: Jabber user got online or just registered
+    - legacy_logout: Jabber user got offline or just unregistered
+    - legacy_presence_unavailable: Jabber user sent an unavailable presence to a legacy contact
+    - gateway_message: Jabber user sent a direct message to the gateway component
+    - legacy_message: Jabber user sent a message to the legacy network
+
+
+    Plugin Parameters:
+
+    - `component_name`: (str) Name of the entity
+    - `type`: (str) Type of the gateway identity. Should be the name of the legacy service
+    - `needs_registration`: (bool) If set to True, messages received from unregistered users will
+      not be transmitted to the legacy service
+
+    API:
+
+    - legacy_contact_add(jid, node, ifrom: JID, args: JID): Add contact on the legacy service.
+      Should raise LegacyError if anything goes wrong in the process.
+      `ifrom` is the gateway user's JID and `args` is the legacy contact's JID.
+    - legacy_contact_remove(jid, node, ifrom: JID, args: JID): Remove a contact.
+
+    """
+
+    name = "xep_0100"
+    description = "XEP-0100: Gateway interaction"
+    dependencies = {
+        "xep_0030",  # Service discovery
+        "xep_0077",  # In band registration
+    }
+
+    default_config = {
+        "component_name": "SliXMPP gateway",
+        "type": "xmpp",
+        "needs_registration": True,
+    }
+
+    def plugin_init(self):
+        if not self.xmpp.is_component:
+            log.error("Only components can be gateways, aborting plugin load")
+            return
+
+        self.xmpp["xep_0030"].add_identity(
+            name=self.component_name, category="gateway", itype=self.type
+        )
+
+        self.api.register(self._legacy_contact_remove, "legacy_contact_remove")
+        self.api.register(self._legacy_contact_add, "legacy_contact_add")
+
+        # Without that BaseXMPP sends unsub/unavailable on sub requests and we don't want that
+        self.xmpp.client_roster.auto_authorize = True
+        self.xmpp.client_roster.auto_subscribe = False
+
+        self.xmpp.add_event_handler("user_register", self.on_user_register)
+        self.xmpp.add_event_handler("user_unregister", self.on_user_unregister)
+        self.xmpp.add_event_handler("presence_available", self.on_presence_available)
+        self.xmpp.add_event_handler(
+            "presence_unavailable", self.on_presence_unavailable
+        )
+        self.xmpp.add_event_handler("presence_subscribe", self.on_presence_subscribe)
+        self.xmpp.add_event_handler(
+            "presence_unsubscribe", self.on_presence_unsubscribe
+        )
+        self.xmpp.add_event_handler("message", self.on_message)
+
+    def plugin_end(self):
+        if not self.xmpp.is_component:
+            return
+
+        self.xmpp.del_event_handler("user_register", self.on_user_register)
+        self.xmpp.del_event_handler("user_unregister", self.on_user_unregister)
+        self.xmpp.del_event_handler("presence_available", self.on_presence_available)
+        self.xmpp.del_event_handler(
+            "presence_unavailable", self.on_presence_unavailable
+        )
+        self.xmpp.del_event_handler("presence_subscribe", self.on_presence_subscribe)
+        self.xmpp.del_event_handler("message", self.on_message)
+        self.xmpp.del_event_handler(
+            "presence_unsubscribe", self.on_presence_unsubscribe
+        )
+
+    async def get_user(self, stanza):
+        return await self.xmpp["xep_0077"].api["user_get"](None, None, None, stanza)
+
+    def send_presence(self, pto, ptype=None, pstatus=None, pfrom=None):
+        self.xmpp.send_presence(
+            pfrom=self.xmpp.boundjid.bare,
+            ptype=ptype,
+            pto=pto,
+            pstatus=pstatus,
+        )
+
+    async def on_user_register(self, iq: Iq):
+        user_jid = iq["from"]
+        user = await self.get_user(iq)
+        if user is None:  # This should not happen
+            log.warning(f"{user_jid} has registered but cannot find them in user store")
+        else:
+            log.debug(f"Sending subscription request to {user_jid}")
+            self.xmpp.client_roster.subscribe(user_jid)
+
+    def on_user_unregister(self, iq: Iq):
+        user_jid = iq["from"]
+        log.debug(f"Sending subscription request to {user_jid}")
+        self.xmpp.event("legacy_logout", iq)
+        self.xmpp.client_roster.unsubscribe(iq["from"])
+        self.xmpp.client_roster.remove(iq["from"])
+        log.debug(f"roster: {self.xmpp.client_roster}")
+
+    async def on_presence_available(self, presence: Presence):
+        user_jid = presence["from"]
+        user = await self.get_user(presence)
+        if user is None:
+            log.warning(
+                f"{user_jid} has gotten online but cannot find them in user store"
+            )
+        else:
+            self.xmpp.event("legacy_login", presence)
+            log.debug(f"roster: {self.xmpp.client_roster}")
+            self.send_presence(pto=user_jid.bare, ptype="available")
+
+    async def on_presence_unavailable(self, presence: Presence):
+        user_jid = presence["from"]
+        user = await self.get_user(presence)
+        if user is None:  # This should not happen
+            log.warning(
+                f"{user_jid} has gotten offline but but cannot find them in user store"
+            )
+            return
+
+        if presence["to"] == self.xmpp.boundjid.bare:
+            self.xmpp.event("legacy_logout", presence)
+            self.send_presence(pto=user_jid, ptype="unavailable")
+        else:
+            self.xmpp.event("legacy_presence_unavailable", presence)
+
+    async def _legacy_contact_add(self, jid, node, ifrom, contact_jid: JID):
+        pass
+
+    async def on_presence_subscribe(self, presence: Presence):
+        user_jid = presence["from"]
+        user = await self.get_user(presence)
+        if user is None and self.needs_registration:
+            return
+
+        if presence["to"] == self.xmpp.boundjid.bare:
+            return
+
+        try:
+            await self.api["legacy_contact_add"](
+                ifrom=user_jid,
+                args=presence["to"],
+            )
+        except LegacyError:
+            self.xmpp.send_presence(
+                pfrom=presence["to"],
+                ptype="unsubscribed",
+                pto=user_jid,
+            )
+            return
+        self.xmpp.send_presence(
+            pfrom=presence["to"],
+            ptype="subscribed",
+            pto=user_jid,
+        )
+        self.xmpp.send_presence(
+            pfrom=presence["to"],
+            pto=user_jid,
+        )
+        self.xmpp.send_presence(
+            pfrom=presence["to"],
+            ptype="subscribe",
+            pto=user_jid,
+        )  # TODO: handle resulting subscribed presences
+
+    async def on_presence_unsubscribe(self, presence: Presence):
+        if presence["to"] == self.xmpp.boundjid.bare:
+            # should we trigger unregistering here?
+            return
+
+        user_jid = presence["from"]
+        user = await self.get_user(presence)
+        if user is None:
+            log.debug("Received remove subscription from unregistered user")
+            if self.needs_registration:
+                return
+
+        await self.api["legacy_contact_remove"](ifrom=user_jid, args=presence["to"])
+
+        for ptype in "unsubscribe", "unsubscribed", "unavailable":
+            self.xmpp.send_presence(
+                pfrom=presence["to"],
+                ptype=ptype,
+                pto=user_jid,
+            )
+
+    async def _legacy_contact_remove(self, jid, node, ifrom, contact_jid: JID):
+        pass
+
+    async def on_message(self, msg: Message):
+        if msg["type"] == "groupchat":
+            return  # groupchat messages are out of scope of XEP-0100
+
+        if msg["to"] == self.xmpp.boundjid.bare:
+            # It may be useful to exchange direct messages with the component
+            self.xmpp.event("gateway_message", msg)
+            return
+
+        if self.needs_registration and await self.get_user(msg) is None:
+            return
+
+        self.xmpp.event("legacy_message", msg)
+
+    def transform_legacy_message(
+        self,
+        jabber_user_jid: typing.Union[JID, str],
+        legacy_contact_id: str,
+        body: str,
+        mtype: typing.Optional[str] = None,
+    ):
+        """
+        Transform a legacy message to an XMPP message
+        """
+        # Should escaping legacy IDs to valid JID local parts be handled here?
+        # Maybe by internal API stuff?
+        self.xmpp.send_message(
+            mfrom=JID(f"{legacy_contact_id}@{self.xmpp.boundjid.bare}"),
+            mto=JID(jabber_user_jid).bare,
+            mbody=body,
+            mtype=mtype,
+        )
+
+
+class LegacyError(Exception):
+    pass
+
+
+log = logging.getLogger(__name__)