plugin XEP-0166: new trigger point + coroutines + helper methods:

- a new `XEP-0166_initiate` async trigger point is available
- `initate` is now a coroutine
- `jingleSessionInit` in applications and transports handlers are now called using
  `utils.adDeferred`
- new `getApplication` helper method, to retrieve application from its namespace
- new `getContentData` helper method to retrieve application and its argument from content

sat/plugins/plugin_exp_jingle_stream.py

@@ -17,14 +17,8 @@
 # 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 sat.core.i18n import _, D_
-from sat.core.constants import Const as C
-from sat.core import exceptions
-from sat.core.log import getLogger
-
-log = getLogger(__name__)
-from sat.tools import xml_tools
-from sat.tools import stream
+import errno
+from zope import interface
 from twisted.words.xish import domish
 from twisted.words.protocols.jabber import jid
 from twisted.internet import defer
@@ -33,8 +27,15 @@ from twisted.internet import endpoints
 from twisted.internet import reactor
 from twisted.internet import error
 from twisted.internet import interfaces
-from zope import interface
-import errno
+from sat.core.i18n import _, D_
+from sat.core.constants import Const as C
+from sat.core import exceptions
+from sat.core.log import getLogger
+from sat.tools import xml_tools
+from sat.tools import stream
+
+
+log = getLogger(__name__)
 
 NS_STREAM = "http://salut-a-toi.org/protocol/stream"
 SECURITY_LIMIT = 30
@@ -193,10 +194,9 @@ class JingleStream(object):
 
     def _streamOut(self, to_jid_s, profile_key):
         client = self.host.getClient(profile_key)
-        return self.streamOut(client, jid.JID(to_jid_s))
+        return defer.ensureDeferred(self.streamOut(client, jid.JID(to_jid_s)))
 
-    @defer.inlineCallbacks
-    def streamOut(self, client, to_jid):
+    async def streamOut(self, client, to_jid):
         """send a stream
 
         @param peer_jid(jid.JID): recipient
@@ -207,7 +207,7 @@ class JingleStream(object):
         while True:
             endpoint = endpoints.TCP4ServerEndpoint(reactor, port)
             try:
-                port_listening = yield endpoint.listen(factory)
+                port_listening = await endpoint.listen(factory)
             except error.CannotListenError as e:
                 if e.socketError.errno == errno.EADDRINUSE:
                     port += 1
@@ -216,7 +216,8 @@ class JingleStream(object):
             else:
                 factory.port_listening = port_listening
                 break
-        self._j.initiate(
+        # we don't want to wait for IQ result of initiate
+        defer.ensureDeferred(self._j.initiate(
             client,
             to_jid,
             [
@@ -226,8 +227,8 @@ class JingleStream(object):
                     "app_kwargs": {"stream_object": factory},
                 }
             ],
-        )
-        defer.returnValue(str(port))
+        ))
+        return str(port)
 
     def jingleSessionInit(self, client, session, content_name, stream_object):
         content_data = session["contents"][content_name]