plugin ip, params: plugin IP discovery, first draft:

- a dedicated plugin now manage IP discovery, for now it uses external website, but it should implement XEP-0279 soon
    - a permission is requested to user for calling an external website. Once the permission is granted (it's global), it is not asked anymore.
    - the ip is discovered on demand, and cache is kept for the session.
    - memory.params.getParamA has a new parameter use_default, which allow to get None when a parameter is not set, instead of the default value.
        This allow to detected when we need to do the first permission request. memory.getParamA don't have this parameter.

src/plugins/plugin_misc_ip.py

@@ -0,0 +1,101 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# SAT plugin for IP address discovery
+# Copyright (C) 2009, 2010, 2011, 2012, 2013, 2014, 2015 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 sat.core.i18n import _, D_
+from sat.core.constants import Const as C
+from sat.core.log import getLogger
+log = getLogger(__name__)
+from sat.tools import xml_tools
+from twisted.web.client import getPage
+import urlparse
+
+
+PLUGIN_INFO = {
+    "name": "IP discovery",
+    "import_name": "IP",
+    "type": C.PLUG_TYPE_MISC,
+    "main": "IPPlugin",
+    "handler": "no",
+    "description": _("""This plugin help to discover our external IP address.""")
+}
+
+GET_IP_PAGE = "http://www.goffi.org/sat_tools/get_ip.php" # This page must only return external IP of the requester
+GET_IP_LABEL = D_(u"Allow external get IP")
+GET_IP_CATEGORY = "General"
+GET_IP_NAME = "allow_get_ip"
+GET_IP_CONFIRM_TITLE = D_(u"Confirm external site request")
+GET_IP_CONFIRM = D_(u"""To facilitate data transfer, we need to contact a website.
+A request will be done on {page}
+That means that administrators of {domain} can know that you use "{app_name}" and your IP Address.
+
+IP address is an identifier to locate you on Internet (similar to a phone number).
+
+Do you agree to do this request ?
+""").format(
+    page = GET_IP_PAGE,
+    domain = urlparse.urlparse(GET_IP_PAGE).netloc,
+    app_name = C.APP_NAME)
+
+PARAMS = """
+    <params>
+    <general>
+    <category name="{category}">
+        <param name="{name}" label="{label}" type="bool" />
+    </category>
+    </general>
+    </params>
+    """.format(category=GET_IP_CATEGORY, name=GET_IP_NAME, label=GET_IP_LABEL)
+
+class IPPlugin(object):
+
+    def __init__(self, host):
+        log.info(_("plugin IP discovery initialization"))
+        self.host = host
+        host.memory.updateParams(PARAMS)
+
+    def profileConnected(self, profile):
+        client = self.host.getClient(profile)
+        # XXX: we keep cache only for profile session as ip can change between them
+        client._ip_cache = None
+
+    def getIP(self, profile):
+        """Try to discover external IP
+
+        @param profile: %(doc_profile)s
+        @return (deferred): external IP address or None if it can't be discovered
+        """
+        client = self.host.getClient(profile)
+        if client._ip_cache is not None:
+            return client._ip_cache
+
+        allow_get_ip = self.host.memory.params.getParamA(GET_IP_NAME, GET_IP_CATEGORY, use_default=False)
+
+        if allow_get_ip is None:
+            # we don't have autorisation from user yet to use get_ip, we ask him
+            confirm_d = xml_tools.deferConfirm(self.host, _(GET_IP_CONFIRM), _(GET_IP_CONFIRM_TITLE), profile=profile)
+            def setParam(allowed):
+                # FIXME: we need to use boolConst as setParam only manage str/unicode
+                #        need to be fixed when params will be refactored
+                self.host.memory.setParam(GET_IP_NAME, C.boolConst(allowed), GET_IP_CATEGORY)
+                return self.getIP(profile)
+
+            return confirm_d.addCallback(setParam)
+
+
+        return getPage(GET_IP_PAGE) if allow_get_ip else None