"AssertionError: paths must be Unicode strings" when starting a node

[daira]

[reported by ekodo]

I have tried to install tahoe-lafs on ubuntu 14.04.1 from github source.

All tests are passed, like in travis. But when I try to run the binary: tahoe start

I got the following error:

STARTING '/home/tahoe_user/.tahoe'
starting node in '/home/tahoe_user/.tahoe'
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/allmydata/scripts/runner.py", line 156, in run
    rc = runner(sys.argv[1:], install_node_control=install_node_control)
  File "/usr/local/lib/python2.7/dist-packages/allmydata/scripts/runner.py", line 135, in runner
    rc = startstop_node.dispatch[command](so, stdout, stderr)
  File "/usr/local/lib/python2.7/dist-packages/allmydata/scripts/startstop_node.py", line 159, in start
    twistd.runApp(twistd_config)
  File "/usr/lib/python2.7/dist-packages/twisted/scripts/twistd.py", line 23, in runApp
    _SomeApplicationRunner(config).run()
  File "/usr/lib/python2.7/dist-packages/twisted/application/app.py", line 376, in run
    self.application = self.createOrGetApplication()
  File "/usr/lib/python2.7/dist-packages/twisted/application/app.py", line 436, in createOrGetApplication
    ser = plg.makeService(self.config.subOptions)
  File "/usr/local/lib/python2.7/dist-packages/allmydata/scripts/startstop_node.py", line 68, in makeService
    return Client(self.basedir)
  File "/usr/local/lib/python2.7/dist-packages/allmydata/client.py", line 151, in __init__
    self.init_sftp_server()
  File "/usr/local/lib/python2.7/dist-packages/allmydata/client.py", line 479, in init_sftp_server
    sftp_portstr, pubkey_file, privkey_file)
  File "/usr/local/lib/python2.7/dist-packages/allmydata/frontends/sftpd.py", line 1988, in __init__
    c = AccountFileChecker(self, accountfile)
  File "/usr/local/lib/python2.7/dist-packages/allmydata/frontends/auth.py", line 34, in __init__
    for line in open(abspath_expanduser_unicode(accountfile), "r"):
  File "/usr/local/lib/python2.7/dist-packages/allmydata/util/fileutil.py", line 314, in abspath_expanduser_unicode
    raise AssertionError("paths must be Unicode strings")
AssertionError: paths must be Unicode strings

And here are my version:

/usr/local/bin/tahoe --version-and-path
allmydata-tahoe: 1.10.0.post272 [master: e9e63c5e72619f4e5811cd1eed31e344db6236c8] (/usr/local/lib/python2.7/dist-packages)
foolscap: 0.6.4 (/usr/lib/python2.7/dist-packages)
pycryptopp: 0.6.0.1206569328141510525648634803928199668821045408958 (/usr/lib/python2.7/dist-packages)
zfec: 1.4.5 (/usr/lib/python2.7/dist-packages)
Twisted: 13.2.0 (/usr/lib/python2.7/dist-packages)
Nevow: 0.11.1 (/usr/local/lib/python2.7/dist-packages)
zope.interface: unknown (/usr/lib/python2.7/dist-packages/zope)
python: 2.7.6 (/usr/bin/python)
platform: Linux-Ubuntu_14.04-x86_64-64bit_ELF (None)
pyOpenSSL: 0.13 (/usr/lib/python2.7/dist-packages)
simplejson: 3.3.1 (/usr/lib/python2.7/dist-packages)
pycrypto: 2.6.1 (/usr/lib/python2.7/dist-packages)
pyasn1: 0.1.7 (/usr/lib/python2.7/dist-packages)
mock: 1.0.1 (/usr/lib/python2.7)
setuptools: 3.3 (/usr/lib/python2.7/dist-packages)
service-identity: 14.0.0 (/usr/local/lib/python2.7/dist-packages)
characteristic: 14.3.0 (/usr/local/lib/python2.7)
pyasn1-modules: 0.0.5 (/usr/local/lib/python2.7/dist-packages)

[warner]

Do we know what the tahoe.cfg held for the SFTP accountfile? Was it ASCII, unicode, or maybe an empty string?

[warner]

It looks like src/allmydata/frontends/auth.py was recently (30-Jan-2015, in 14f7830) changed to use abspath_expanduser_unicode() instead of os.path.expanduser(). The config code has always been providing bytestrings, but it previously didn't matter because nothing was checking for unicode-ness. With 14f7830, auth.py started rejecting the config strings.

The fix will be to change Client.init_sftp_server to convert the self.get_config strings into unicode before delivering them to SFTPServer.

[daira]

Replying to warner:

Do we know what the tahoe.cfg held for the SFTP accountfile? Was it ASCII, unicode, or maybe an empty string?

We know that the home directory path was ASCII, and the accountfile path was ~/.tahoe/private/accounts.

[daira]

See the ​https://github.com/tahoe-lafs/tahoe-lafs/commits/2388.fix-paths-must-be-unicode-strings.1 branch for an untested fix.

[warner]

​https://github.com/tahoe-lafs/tahoe-lafs/pull/147 adds a test and fixes the missing imports.

[daira]

Rebased and landed in [21226cbb82a51c98361e02a9ac3df5c05f9474a8], [3066039f0f802406675e30f5521f98fb79d444a8], and [b6be693cbedb201206a73439584d28b2aeb3ac38].