]> git.rkrishnan.org Git - tahoe-lafs/tahoe-lafs.git/blobdiff - src/allmydata/test/test_client.py
Eliminate mock dependency.
[tahoe-lafs/tahoe-lafs.git] / src / allmydata / test / test_client.py
index 244278f510cab970c0ac060b2f81efca7ab28b15..dfd9b8de7f954ddb0baa4371953d8b51fd5dbdd5 100644 (file)
-
-import os
+import os, sys
+import twisted
 from twisted.trial import unittest
 from twisted.application import service
-from twisted.python import log
 
 import allmydata
+import allmydata.frontends.drop_upload
+import allmydata.util.log
+
+from allmydata.node import Node, OldConfigError, OldConfigOptionError, MissingConfigEntry, UnescapedHashError
+from allmydata.frontends.auth import NeedRootcapLookupScheme
 from allmydata import client
 from allmydata.storage_client import StorageFarmBroker
-from allmydata.introducer.client import IntroducerClient
+from allmydata.manhole import AuthorizedKeysManhole
 from allmydata.util import base32, fileutil
 from allmydata.interfaces import IFilesystemNode, IFileNode, \
      IImmutableFileNode, IMutableFileNode, IDirectoryNode
 from foolscap.api import flushEventualQueue
 import allmydata.test.common_util as testutil
 
-class FakeIntroducerClient(IntroducerClient):
-    def __init__(self):
-        self._connections = set()
-    def add_peer(self, nodeid):
-        entry = (nodeid, "storage", "rref")
-        self._connections.add(entry)
-    def remove_all_peers(self):
-        self._connections.clear()
 
 BASECONFIG = ("[client]\n"
               "introducer.furl = \n"
               )
 
+BASECONFIG_I = ("[client]\n"
+              "introducer.furl = %s\n"
+              )
+
 class Basic(testutil.ReallyEqualMixin, unittest.TestCase):
     def test_loadable(self):
         basedir = "test_client.Basic.test_loadable"
         os.mkdir(basedir)
-        open(os.path.join(basedir, "introducer.furl"), "w").write("")
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"), \
+                           BASECONFIG)
         client.Client(basedir)
 
-    def test_loadable_old_config_bits(self):
-        basedir = "test_client.Basic.test_loadable_old_config_bits"
+    def test_comment(self):
+        should_fail = [r"test#test", r"#testtest", r"test\\#test"]
+        should_not_fail = [r"test\#test", r"test\\\#test", r"testtest"]
+
+        basedir = "test_client.Basic.test_comment"
         os.mkdir(basedir)
-        open(os.path.join(basedir, "introducer.furl"), "w").write("")
-        open(os.path.join(basedir, "no_storage"), "w").write("")
-        open(os.path.join(basedir, "readonly_storage"), "w").write("")
-        open(os.path.join(basedir, "debug_discard_storage"), "w").write("")
-        c = client.Client(basedir)
-        try:
-            c.getServiceNamed("storage")
-            self.fail("that was supposed to fail")
-        except KeyError:
-            pass
 
-    def test_loadable_old_storage_config_bits(self):
-        basedir = "test_client.Basic.test_loadable_old_storage_config_bits"
+        def write_config(s):
+            config = ("[client]\n"
+                      "introducer.furl = %s\n" % s)
+            fileutil.write(os.path.join(basedir, "tahoe.cfg"), config)
+
+        for s in should_fail:
+            self.failUnless(Node._contains_unescaped_hash(s))
+            write_config(s)
+            self.failUnlessRaises(UnescapedHashError, client.Client, basedir)
+
+        for s in should_not_fail:
+            self.failIf(Node._contains_unescaped_hash(s))
+            write_config(s)
+            client.Client(basedir)
+
+
+    def test_error_on_old_config_files(self):
+        basedir = "test_client.Basic.test_error_on_old_config_files"
         os.mkdir(basedir)
-        open(os.path.join(basedir, "introducer.furl"), "w").write("")
-        open(os.path.join(basedir, "readonly_storage"), "w").write("")
-        open(os.path.join(basedir, "debug_discard_storage"), "w").write("")
-        c = client.Client(basedir)
-        s = c.getServiceNamed("storage")
-        self.failUnless(s.no_storage)
-        self.failUnless(s.readonly_storage)
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"),
+                       BASECONFIG +
+                       "[storage]\n" +
+                       "enabled = false\n" +
+                       "reserved_space = bogus\n")
+        fileutil.write(os.path.join(basedir, "introducer.furl"), "")
+        fileutil.write(os.path.join(basedir, "no_storage"), "")
+        fileutil.write(os.path.join(basedir, "readonly_storage"), "")
+        fileutil.write(os.path.join(basedir, "debug_discard_storage"), "")
+
+        logged_messages = []
+        self.patch(twisted.python.log, 'msg', logged_messages.append)
+
+        e = self.failUnlessRaises(OldConfigError, client.Client, basedir)
+        abs_basedir = fileutil.abspath_expanduser_unicode(unicode(basedir)).encode(sys.getfilesystemencoding())
+        self.failUnlessIn(os.path.join(abs_basedir, "introducer.furl"), e.args[0])
+        self.failUnlessIn(os.path.join(abs_basedir, "no_storage"), e.args[0])
+        self.failUnlessIn(os.path.join(abs_basedir, "readonly_storage"), e.args[0])
+        self.failUnlessIn(os.path.join(abs_basedir, "debug_discard_storage"), e.args[0])
+
+        for oldfile in ['introducer.furl', 'no_storage', 'readonly_storage',
+                        'debug_discard_storage']:
+            logged = [ m for m in logged_messages if
+                       ("Found pre-Tahoe-LAFS-v1.3 configuration file" in str(m) and oldfile in str(m)) ]
+            self.failUnless(logged, (oldfile, logged_messages))
+
+        for oldfile in [
+            'nickname', 'webport', 'keepalive_timeout', 'log_gatherer.furl',
+            'disconnect_timeout', 'advertised_ip_addresses', 'helper.furl',
+            'key_generator.furl', 'stats_gatherer.furl', 'sizelimit',
+            'run_helper']:
+            logged = [ m for m in logged_messages if
+                       ("Found pre-Tahoe-LAFS-v1.3 configuration file" in str(m) and oldfile in str(m)) ]
+            self.failIf(logged, (oldfile, logged_messages))
 
     def test_secrets(self):
         basedir = "test_client.Basic.test_secrets"
         os.mkdir(basedir)
-        open(os.path.join(basedir, "introducer.furl"), "w").write("")
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"), \
+                           BASECONFIG)
         c = client.Client(basedir)
         secret_fname = os.path.join(basedir, "private", "secret")
         self.failUnless(os.path.exists(secret_fname), secret_fname)
@@ -71,86 +109,166 @@ class Basic(testutil.ReallyEqualMixin, unittest.TestCase):
         cancel_secret = c.get_cancel_secret()
         self.failUnless(base32.b2a(cancel_secret))
 
+    def test_nodekey_yes_storage(self):
+        basedir = "test_client.Basic.test_nodekey_yes_storage"
+        os.mkdir(basedir)
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"),
+                       BASECONFIG)
+        c = client.Client(basedir)
+        self.failUnless(c.get_long_nodeid().startswith("v0-"))
+
+    def test_nodekey_no_storage(self):
+        basedir = "test_client.Basic.test_nodekey_no_storage"
+        os.mkdir(basedir)
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"),
+                       BASECONFIG + "[storage]\n" + "enabled = false\n")
+        c = client.Client(basedir)
+        self.failUnless(c.get_long_nodeid().startswith("v0-"))
+
     def test_reserved_1(self):
         basedir = "client.Basic.test_reserved_1"
         os.mkdir(basedir)
-        f = open(os.path.join(basedir, "tahoe.cfg"), "w")
-        f.write(BASECONFIG)
-        f.write("[storage]\n")
-        f.write("enabled = true\n")
-        f.write("reserved_space = 1000\n")
-        f.close()
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"), \
+                           BASECONFIG + \
+                           "[storage]\n" + \
+                           "enabled = true\n" + \
+                           "reserved_space = 1000\n")
         c = client.Client(basedir)
-        self.failUnlessReallyEqual(c.getServiceNamed("storage").reserved_space, 1000)
+        self.failUnlessEqual(c.getServiceNamed("storage").reserved_space, 1000)
 
     def test_reserved_2(self):
         basedir = "client.Basic.test_reserved_2"
         os.mkdir(basedir)
-        f = open(os.path.join(basedir, "tahoe.cfg"), "w")
-        f.write(BASECONFIG)
-        f.write("[storage]\n")
-        f.write("enabled = true\n")
-        f.write("reserved_space = 10K\n")
-        f.close()
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"),  \
+                           BASECONFIG + \
+                           "[storage]\n" + \
+                           "enabled = true\n" + \
+                           "reserved_space = 10K\n")
         c = client.Client(basedir)
-        self.failUnlessReallyEqual(c.getServiceNamed("storage").reserved_space, 10*1000)
+        self.failUnlessEqual(c.getServiceNamed("storage").reserved_space, 10*1000)
 
     def test_reserved_3(self):
         basedir = "client.Basic.test_reserved_3"
         os.mkdir(basedir)
-        f = open(os.path.join(basedir, "tahoe.cfg"), "w")
-        f.write(BASECONFIG)
-        f.write("[storage]\n")
-        f.write("enabled = true\n")
-        f.write("reserved_space = 5mB\n")
-        f.close()
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"), \
+                           BASECONFIG + \
+                           "[storage]\n" + \
+                           "enabled = true\n" + \
+                           "reserved_space = 5mB\n")
         c = client.Client(basedir)
-        self.failUnlessReallyEqual(c.getServiceNamed("storage").reserved_space,
+        self.failUnlessEqual(c.getServiceNamed("storage").reserved_space,
                              5*1000*1000)
 
     def test_reserved_4(self):
         basedir = "client.Basic.test_reserved_4"
         os.mkdir(basedir)
-        f = open(os.path.join(basedir, "tahoe.cfg"), "w")
-        f.write(BASECONFIG)
-        f.write("[storage]\n")
-        f.write("enabled = true\n")
-        f.write("reserved_space = 78Gb\n")
-        f.close()
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"), \
+                           BASECONFIG + \
+                           "[storage]\n" + \
+                           "enabled = true\n" + \
+                           "reserved_space = 78Gb\n")
         c = client.Client(basedir)
-        self.failUnlessReallyEqual(c.getServiceNamed("storage").reserved_space,
-                                   78*1000*1000*1000)
+        self.failUnlessEqual(c.getServiceNamed("storage").reserved_space,
+                             78*1000*1000*1000)
 
     def test_reserved_bad(self):
         basedir = "client.Basic.test_reserved_bad"
         os.mkdir(basedir)
-        f = open(os.path.join(basedir, "tahoe.cfg"), "w")
-        f.write(BASECONFIG)
-        f.write("[storage]\n")
-        f.write("enabled = true\n")
-        f.write("reserved_space = bogus\n")
-        f.close()
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"), \
+                           BASECONFIG + \
+                           "[storage]\n" + \
+                           "enabled = true\n" + \
+                           "reserved_space = bogus\n")
+        self.failUnlessRaises(ValueError, client.Client, basedir)
+
+    def test_web_staticdir(self):
+        basedir = u"client.Basic.test_web_staticdir"
+        os.mkdir(basedir)
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"),
+                       BASECONFIG +
+                       "[node]\n" +
+                       "web.port = tcp:0:interface=127.0.0.1\n" +
+                       "web.static = relative\n")
+        c = client.Client(basedir)
+        w = c.getServiceNamed("webish")
+        abs_basedir = fileutil.abspath_expanduser_unicode(basedir)
+        expected = fileutil.abspath_expanduser_unicode(u"relative", abs_basedir)
+        self.failUnlessReallyEqual(w.staticdir, expected)
+
+    def test_manhole_keyfile(self):
+        basedir = u"client.Basic.test_manhole_keyfile"
+        os.mkdir(basedir)
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"),
+                       BASECONFIG +
+                       "[node]\n" +
+                       "ssh.port = tcp:0:interface=127.0.0.1\n" +
+                       "ssh.authorized_keys_file = relative\n")
         c = client.Client(basedir)
-        self.failUnlessReallyEqual(c.getServiceNamed("storage").reserved_space, 0)
+        m = [s for s in c if isinstance(s, AuthorizedKeysManhole)][0]
+        abs_basedir = fileutil.abspath_expanduser_unicode(basedir)
+        expected = fileutil.abspath_expanduser_unicode(u"relative", abs_basedir)
+        self.failUnlessReallyEqual(m.keyfile, expected)
+
+    # TODO: also test config options for SFTP.
+
+    def test_ftp_auth_keyfile(self):
+        basedir = u"client.Basic.test_ftp_auth_keyfile"
+        os.mkdir(basedir)
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"),
+                       (BASECONFIG +
+                        "[ftpd]\n"
+                        "enabled = true\n"
+                        "port = tcp:0:interface=127.0.0.1\n"
+                        "accounts.file = private/accounts\n"))
+        os.mkdir(os.path.join(basedir, "private"))
+        fileutil.write(os.path.join(basedir, "private", "accounts"), "\n")
+        c = client.Client(basedir) # just make sure it can be instantiated
+        del c
+
+    def test_ftp_auth_url(self):
+        basedir = u"client.Basic.test_ftp_auth_url"
+        os.mkdir(basedir)
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"),
+                       (BASECONFIG +
+                        "[ftpd]\n"
+                        "enabled = true\n"
+                        "port = tcp:0:interface=127.0.0.1\n"
+                        "accounts.url = http://0.0.0.0/\n"))
+        c = client.Client(basedir) # just make sure it can be instantiated
+        del c
+
+    def test_ftp_auth_no_accountfile_or_url(self):
+        basedir = u"client.Basic.test_ftp_auth_no_accountfile_or_url"
+        os.mkdir(basedir)
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"),
+                       (BASECONFIG +
+                        "[ftpd]\n"
+                        "enabled = true\n"
+                        "port = tcp:0:interface=127.0.0.1\n"))
+        self.failUnlessRaises(NeedRootcapLookupScheme, client.Client, basedir)
 
     def _permute(self, sb, key):
-        return [ peerid
-                 for (peerid,rref) in sb.get_servers_for_index(key) ]
+        return [ s.get_longname() for s in sb.get_servers_for_psi(key) ]
 
     def test_permute(self):
         sb = StorageFarmBroker(None, True)
         for k in ["%d" % i for i in range(5)]:
-            sb.test_add_server(k, None)
+            ann = {"anonymous-storage-FURL": "pb://abcde@nowhere/fake",
+                   "permutation-seed-base32": base32.b2a(k) }
+            sb.test_add_rref(k, "rref", ann)
 
         self.failUnlessReallyEqual(self._permute(sb, "one"), ['3','1','0','4','2'])
         self.failUnlessReallyEqual(self._permute(sb, "two"), ['0','4','2','1','3'])
-        sb.test_servers.clear()
+        sb.servers.clear()
         self.failUnlessReallyEqual(self._permute(sb, "one"), [])
 
     def test_versions(self):
         basedir = "test_client.Basic.test_versions"
         os.mkdir(basedir)
-        open(os.path.join(basedir, "introducer.furl"), "w").write("")
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"), \
+                           BASECONFIG + \
+                           "[storage]\n" + \
+                           "enabled = true\n")
         c = client.Client(basedir)
         ss = c.getServiceNamed("storage")
         verdict = ss.remote_get_version()
@@ -160,13 +278,102 @@ class Basic(testutil.ReallyEqualMixin, unittest.TestCase):
         self.failUnless("." in str(allmydata.__full_version__),
                         "non-numeric version in '%s'" % allmydata.__version__)
         all_versions = allmydata.get_package_versions_string()
-        self.failUnless("allmydata-tahoe" in all_versions)
-        log.msg("tahoe versions: %s" % all_versions)
+        self.failUnless(allmydata.__appname__ in all_versions)
         # also test stats
         stats = c.get_stats()
         self.failUnless("node.uptime" in stats)
         self.failUnless(isinstance(stats["node.uptime"], float))
 
+    def test_helper_furl(self):
+        basedir = "test_client.Basic.test_helper_furl"
+        os.mkdir(basedir)
+
+        def _check(config, expected_furl):
+            fileutil.write(os.path.join(basedir, "tahoe.cfg"),
+                           BASECONFIG + config)
+            c = client.Client(basedir)
+            uploader = c.getServiceNamed("uploader")
+            furl, connected = uploader.get_helper_info()
+            self.failUnlessEqual(furl, expected_furl)
+
+        _check("", None)
+        _check("helper.furl =\n", None)
+        _check("helper.furl = \n", None)
+        _check("helper.furl = None", None)
+        _check("helper.furl = pb://blah\n", "pb://blah")
+
+    def test_create_drop_uploader(self):
+        class MockDropUploader(service.MultiService):
+            name = 'drop-upload'
+
+            def __init__(self, client, upload_dircap, local_dir_utf8, inotify=None):
+                service.MultiService.__init__(self)
+                self.client = client
+                self.upload_dircap = upload_dircap
+                self.local_dir_utf8 = local_dir_utf8
+                self.inotify = inotify
+
+        self.patch(allmydata.frontends.drop_upload, 'DropUploader', MockDropUploader)
+
+        upload_dircap = "URI:DIR2:blah"
+        local_dir_utf8 = u"loc\u0101l_dir".encode('utf-8')
+        config = (BASECONFIG +
+                  "[storage]\n" +
+                  "enabled = false\n" +
+                  "[drop_upload]\n" +
+                  "enabled = true\n")
+
+        basedir1 = "test_client.Basic.test_create_drop_uploader1"
+        os.mkdir(basedir1)
+        fileutil.write(os.path.join(basedir1, "tahoe.cfg"),
+                       config + "local.directory = " + local_dir_utf8 + "\n")
+        self.failUnlessRaises(MissingConfigEntry, client.Client, basedir1)
+
+        fileutil.write(os.path.join(basedir1, "tahoe.cfg"), config)
+        fileutil.write(os.path.join(basedir1, "private", "drop_upload_dircap"), "URI:DIR2:blah")
+        self.failUnlessRaises(MissingConfigEntry, client.Client, basedir1)
+
+        fileutil.write(os.path.join(basedir1, "tahoe.cfg"),
+                       config + "upload.dircap = " + upload_dircap + "\n")
+        self.failUnlessRaises(OldConfigOptionError, client.Client, basedir1)
+
+        fileutil.write(os.path.join(basedir1, "tahoe.cfg"),
+                       config + "local.directory = " + local_dir_utf8 + "\n")
+        c1 = client.Client(basedir1)
+        uploader = c1.getServiceNamed('drop-upload')
+        self.failUnless(isinstance(uploader, MockDropUploader), uploader)
+        self.failUnlessReallyEqual(uploader.client, c1)
+        self.failUnlessReallyEqual(uploader.upload_dircap, upload_dircap)
+        self.failUnlessReallyEqual(uploader.local_dir_utf8, local_dir_utf8)
+        self.failUnless(uploader.inotify is None, uploader.inotify)
+        self.failUnless(uploader.running)
+
+        class Boom(Exception):
+            pass
+        def BoomDropUploader(client, upload_dircap, local_dir_utf8, inotify=None):
+            raise Boom()
+
+        logged_messages = []
+        def mock_log(*args, **kwargs):
+            logged_messages.append("%r %r" % (args, kwargs))
+        self.patch(allmydata.util.log, 'msg', mock_log)
+        self.patch(allmydata.frontends.drop_upload, 'DropUploader', BoomDropUploader)
+
+        basedir2 = "test_client.Basic.test_create_drop_uploader2"
+        os.mkdir(basedir2)
+        os.mkdir(os.path.join(basedir2, "private"))
+        fileutil.write(os.path.join(basedir2, "tahoe.cfg"),
+                       BASECONFIG +
+                       "[drop_upload]\n" +
+                       "enabled = true\n" +
+                       "local.directory = " + local_dir_utf8 + "\n")
+        fileutil.write(os.path.join(basedir2, "private", "drop_upload_dircap"), "URI:DIR2:blah")
+        c2 = client.Client(basedir2)
+        self.failUnlessRaises(KeyError, c2.getServiceNamed, 'drop-upload')
+        self.failUnless([True for arg in logged_messages if "Boom" in arg],
+                        logged_messages)
+
+
 def flush_but_dont_ignore(res):
     d = flushEventualQueue()
     def _done(ignored):
@@ -188,15 +395,15 @@ class Run(unittest.TestCase, testutil.StallMixin):
         basedir = "test_client.Run.test_loadable"
         os.mkdir(basedir)
         dummy = "pb://wl74cyahejagspqgy4x5ukrvfnevlknt@127.0.0.1:58889/bogus"
-        open(os.path.join(basedir, "introducer.furl"), "w").write(dummy)
-        open(os.path.join(basedir, "suicide_prevention_hotline"), "w")
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"), BASECONFIG_I % dummy)
+        fileutil.write(os.path.join(basedir, client.Client.EXIT_TRIGGER_FILE), "")
         client.Client(basedir)
 
     def test_reloadable(self):
         basedir = "test_client.Run.test_reloadable"
         os.mkdir(basedir)
         dummy = "pb://wl74cyahejagspqgy4x5ukrvfnevlknt@127.0.0.1:58889/bogus"
-        open(os.path.join(basedir, "introducer.furl"), "w").write(dummy)
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"), BASECONFIG_I % dummy)
         c1 = client.Client(basedir)
         c1.setServiceParent(self.sparent)
 
@@ -212,13 +419,13 @@ class Run(unittest.TestCase, testutil.StallMixin):
         d.addCallback(self.stall, delay=2.0)
         def _restart(res):
             # TODO: pause for slightly over one second, to let
-            # Client._check_hotline poll the file once. That will exercise
+            # Client._check_exit_trigger poll the file once. That will exercise
             # another few lines. Then add another test in which we don't
-            # update the file at all, and watch to see the node shutdown. (to
-            # do this, use a modified node which overrides Node.shutdown(),
-            # also change _check_hotline to use it instead of a raw
+            # update the file at all, and watch to see the node shutdown.
+            # (To do this, use a modified node which overrides Node.shutdown(),
+            # also change _check_exit_trigger to use it instead of a raw
             # reactor.stop, also instrument the shutdown event in an
-            # attribute that we can check)
+            # attribute that we can check.)
             c2 = client.Client(basedir)
             c2.setServiceParent(self.sparent)
             return c2.disownServiceParent()
@@ -229,9 +436,7 @@ class NodeMaker(testutil.ReallyEqualMixin, unittest.TestCase):
     def test_maker(self):
         basedir = "client/NodeMaker/maker"
         fileutil.make_dirs(basedir)
-        f = open(os.path.join(basedir, "tahoe.cfg"), "w")
-        f.write(BASECONFIG)
-        f.close()
+        fileutil.write(os.path.join(basedir, "tahoe.cfg"), BASECONFIG)
         c = client.Client(basedir)
 
         n = c.create_node_from_uri("URI:CHK:6nmrpsubgbe57udnexlkiwzmlu:bjt7j6hshrlmadjyr7otq3dc24end5meo5xcr5xe5r663po6itmq:3:10:7277")
@@ -243,6 +448,18 @@ class NodeMaker(testutil.ReallyEqualMixin, unittest.TestCase):
         self.failUnless(n.is_readonly())
         self.failIf(n.is_mutable())
 
+        # Testing #1679. There was a bug that would occur when downloader was
+        # downloading the same readcap more than once concurrently, so the
+        # filenode object was cached, and there was a failure from one of the
+        # servers in one of the download attempts. No subsequent download
+        # attempt would attempt to use that server again, which would lead to
+        # the file being undownloadable until the gateway was restarted. The
+        # current fix for this (hopefully to be superceded by a better fix
+        # eventually) is to prevent re-use of filenodes, so the NodeMaker is
+        # hereby required *not* to cache and re-use filenodes for CHKs.
+        other_n = c.create_node_from_uri("URI:CHK:6nmrpsubgbe57udnexlkiwzmlu:bjt7j6hshrlmadjyr7otq3dc24end5meo5xcr5xe5r663po6itmq:3:10:7277")
+        self.failIf(n is other_n, (n, other_n))
+
         n = c.create_node_from_uri("URI:LIT:n5xgk")
         self.failUnless(IFilesystemNode.providedBy(n))
         self.failUnless(IFileNode.providedBy(n))
@@ -301,6 +518,10 @@ class NodeMaker(testutil.ReallyEqualMixin, unittest.TestCase):
         self.failUnlessReallyEqual(n.get_write_uri(), unknown_rw)
         self.failUnlessReallyEqual(n.get_readonly_uri(), "ro." + unknown_ro)
 
+        # Note: it isn't that we *intend* to deploy non-ASCII caps in
+        # the future, it is that we want to make sure older Tahoe-LAFS
+        # versions wouldn't choke on them if we were to do so. See
+        # #1051 and wiki:NewCapDesign for details.
         unknown_rw = u"lafs://from_the_future_rw_\u263A".encode('utf-8')
         unknown_ro = u"lafs://readonly_from_the_future_ro_\u263A".encode('utf-8')
         n = c.create_node_from_uri(unknown_rw, unknown_ro)