Merge pull request #142 from tahoe-lafs/754.location-AUTO.2

Allow combining autodetected and statically configured locations

docs/configuration.rst

@@ -4,7 +4,7 @@
 Configuring a Tahoe-LAFS node
 =============================
 
-1.   `Node Types`_
+1.  `Node Types`_
 2.  `Overall Node Configuration`_
 3.  `Client Configuration`_
 4.  `Storage Server Configuration`_
@@ -159,6 +159,11 @@ set the ``tub.location`` option described below.
     this when using a Tor proxy to avoid revealing your actual IP address
     through the Introducer announcement.
 
+    If ``tub.location`` is specified, by default it entirely replaces the
+    automatically determined set of IP addresses. To include the automatically
+    determined addresses as well as the specified ones, include the uppercase
+    string "``AUTO``" in the list.
+
     The value is a comma-separated string of host:port location hints, like
     this::
 
@@ -177,6 +182,11 @@ set the ``tub.location`` option described below.
         tub.port = 8098
         tub.location = tahoe.example.com:8098
 
+    * Use a DNS name but also include the default set of addresses::
+
+        tub.port = 8098
+        tub.location = tahoe.example.com:8098,AUTO
+
     * Run a node behind a firewall (which has an external IP address) that
       has been configured to forward port 7912 to our internal node's port
       8098::

src/allmydata/node.py

@@ -326,7 +326,6 @@ class Node(service.MultiService):
 
         service.MultiService.startService(self)
         d = defer.succeed(None)
-        d.addCallback(lambda res: iputil.get_local_addresses_async())
         d.addCallback(self._setup_tub)
         def _ready(res):
             self.log("%s running" % self.NODETYPE)
@@ -389,7 +388,7 @@ class Node(service.MultiService):
     def log(self, *args, **kwargs):
         return log.msg(*args, **kwargs)
 
-    def _setup_tub(self, local_addresses):
+    def _setup_tub(self, ign):
         # we can't get a dynamically-assigned portnum until our Tub is
         # running, which means after startService.
         l = self.tub.getListeners()[0]
@@ -398,13 +397,29 @@ class Node(service.MultiService):
         # next time
         fileutil.write_atomically(self._portnumfile, "%d\n" % portnum, mode="")
 
-        base_location = ",".join([ "%s:%d" % (addr, portnum)
-                                   for addr in local_addresses ])
-        location = self.get_config("node", "tub.location", base_location)
-        self.log("Tub location set to %s" % location)
-        self.tub.setLocation(location)
+        location = self.get_config("node", "tub.location", "AUTO")
 
-        return self.tub
+        # Replace the location "AUTO", if present, with the detected local addresses.
+        split_location = location.split(",")
+        if "AUTO" in split_location:
+            d = iputil.get_local_addresses_async()
+            def _add_local(local_addresses):
+                while "AUTO" in split_location:
+                    split_location.remove("AUTO")
+
+                split_location.extend([ "%s:%d" % (addr, portnum)
+                                        for addr in local_addresses ])
+                return ",".join(split_location)
+            d.addCallback(_add_local)
+        else:
+            d = defer.succeed(location)
+
+        def _got_location(location):
+            self.log("Tub location set to %s" % (location,))
+            self.tub.setLocation(location)
+            return self.tub
+        d.addCallback(_got_location)
+        return d
 
     def when_tub_ready(self):
         return self._tub_ready_observerlist.when_fired()

src/allmydata/test/test_node.py

@@ -9,7 +9,7 @@ from mock import patch
 from foolscap.api import flushEventualQueue
 from twisted.application import service
 from allmydata.node import Node, formatTimeTahoeStyle, MissingConfigEntry
-from allmydata.util import fileutil
+from allmydata.util import fileutil, iputil
 import allmydata.test.common_util as testutil
 
 class LoggingMultiService(service.MultiService):
@@ -33,44 +33,55 @@ class TestCase(testutil.SignalMixin, unittest.TestCase):
         d.addCallback(flushEventualQueue)
         return d
 
-    def test_location(self):
-        basedir = "test_node/test_location"
+    def _test_location(self, basedir, expected_addresses, tub_port=None, tub_location=None, local_addresses=None):
         fileutil.make_dirs(basedir)
         f = open(os.path.join(basedir, 'tahoe.cfg'), 'wt')
         f.write("[node]\n")
-        f.write("tub.location = 1.2.3.4:5\n")
+        if tub_port:
+            f.write("tub.port = %d\n" % (tub_port,))
+        if tub_location is not None:
+            f.write("tub.location = %s\n" % (tub_location,))
         f.close()
 
+        if local_addresses:
+            self.patch(iputil, 'get_local_addresses_async', lambda target=None: defer.succeed(local_addresses))
+
         n = TestNode(basedir)
         n.setServiceParent(self.parent)
         d = n.when_tub_ready()
 
         def _check_addresses(ignored_result):
             furl = n.tub.registerReference(n)
-            self.failUnless("1.2.3.4:5" in furl, furl)
+            for address in expected_addresses:
+                self.failUnlessIn(address, furl)
 
         d.addCallback(_check_addresses)
         return d
 
+    def test_location1(self):
+        return self._test_location(basedir="test_node/test_location1",
+                                   expected_addresses=["192.0.2.0:1234"],
+                                   tub_location="192.0.2.0:1234")
+
     def test_location2(self):
-        basedir = "test_node/test_location2"
-        fileutil.make_dirs(basedir)
-        f = open(os.path.join(basedir, 'tahoe.cfg'), 'wt')
-        f.write("[node]\n")
-        f.write("tub.location = 1.2.3.4:5,example.org:8091\n")
-        f.close()
+        return self._test_location(basedir="test_node/test_location2",
+                                   expected_addresses=["192.0.2.0:1234", "example.org:8091"],
+                                   tub_location="192.0.2.0:1234,example.org:8091")
 
-        n = TestNode(basedir)
-        n.setServiceParent(self.parent)
-        d = n.when_tub_ready()
+    def test_location_not_set(self):
+        """Checks the autogenerated furl when tub.location is not set."""
+        return self._test_location(basedir="test_node/test_location3",
+                                   expected_addresses=["127.0.0.1:1234", "192.0.2.0:1234"],
+                                   tub_port=1234,
+                                   local_addresses=["127.0.0.1", "192.0.2.0"])
 
-        def _check_addresses(ignored_result):
-            furl = n.tub.registerReference(n)
-            self.failUnless("1.2.3.4:5" in furl, furl)
-            self.failUnless("example.org:8091" in furl, furl)
-
-        d.addCallback(_check_addresses)
-        return d
+    def test_location_auto_and_explicit(self):
+        """Checks the autogenerated furl when tub.location contains 'AUTO'."""
+        return self._test_location(basedir="test_node/test_location4",
+                                   expected_addresses=["127.0.0.1:1234", "192.0.2.0:1234", "example.com:4321"],
+                                   tub_port=1234,
+                                   tub_location="AUTO,example.com:4321",
+                                   local_addresses=["127.0.0.1", "192.0.2.0", "example.com:4321"])
 
     def test_tahoe_cfg_utf8(self):
         basedir = "test_node/test_tahoe_cfg_utf8"