Unable to install lxml on OSX using pip: 550 Failed to change directory - pip

Question

I'm trying to install lxml on OSX El Capitan using pip3; lots of googling turned up using STATIC_DEPS, but unfortunately I'm now getting an error that to me seems to imply a missing file in the package:
$ STATIC_DEPS=true pip3 install lxml
Collecting lxml
Using cached https://files.pythonhosted.org/packages/54/a6/43be8cf1cc23e3fa208cab04ba2f9c3b7af0233aab32af6b5089122b44cd/lxml-4.2.3.tar.gz
Complete output from command python setup.py egg_info:
Building lxml version 4.2.3.
Latest version of zlib is 1.2.11
Downloading zlib into libs/zlib-1.2.11.tar.gz from http://zlib.net/zlib-1.2.11.tar.gz
Unpacking zlib-1.2.11.tar.gz into build/tmp
Latest version of libiconv is 1.15
Downloading libiconv into libs/libiconv-1.15.tar.gz from ftp://ftp.gnu.org/pub/gnu/libiconv/libiconv-1.15.tar.gz
Unpacking libiconv-1.15.tar.gz into build/tmp
Latest version of libxml2 is 2.9.8
Downloading libxml2 into libs/libxml2-2.9.8.tar.gz from ftp://xmlsoft.org/libxml2/libxml2-2.9.8.tar.gz
Unpacking libxml2-2.9.8.tar.gz into build/tmp
Latest version of libxslt is 1.1.33
Downloading libxslt into libs/libxslt-1.1.33.tar.gz from ftp://xmlsoft.org/libxml2/libxslt-1.1.33.tar.gz
Traceback (most recent call last):
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 2417, in retrfile
self.ftp.cwd(file)
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/ftplib.py", line 631, in cwd
return self.voidcmd(cmd)
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/ftplib.py", line 278, in voidcmd
return self.voidresp()
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/ftplib.py", line 251, in voidresp
resp = self.getresp()
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/ftplib.py", line 246, in getresp
raise error_perm(resp)
ftplib.error_perm: 550 Failed to change directory.
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 1540, in ftp_open
fp, retrlen = fw.retrfile(file, type)
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 2419, in retrfile
raise URLError('ftp error: %r' % reason) from reason
urllib.error.URLError: <urlopen error ftp error: error_perm('550 Failed to change directory.')>
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/private/var/folders/hp/_4p52dfd7s9cf49p86sg1l_w0000gp/T/pip-install-yjxema7x/lxml/setup.py", line 241, in <module>
**setup_extra_options()
File "/private/var/folders/hp/_4p52dfd7s9cf49p86sg1l_w0000gp/T/pip-install-yjxema7x/lxml/setup.py", line 150, in setup_extra_options
STATIC_CFLAGS, STATIC_BINARIES)
File "/private/var/folders/hp/_4p52dfd7s9cf49p86sg1l_w0000gp/T/pip-install-yjxema7x/lxml/setupinfo.py", line 75, in ext_modules
multicore=OPTION_MULTICORE)
File "/private/var/folders/hp/_4p52dfd7s9cf49p86sg1l_w0000gp/T/pip-install-yjxema7x/lxml/buildlibxml.py", line 390, in build_libxml2xslt
libxslt_dir = unpack_tarball(download_libxslt(download_dir, libxslt_version), build_dir)
File "/private/var/folders/hp/_4p52dfd7s9cf49p86sg1l_w0000gp/T/pip-install-yjxema7x/lxml/buildlibxml.py", line 218, in download_libxslt
version_re, filename, version=version)
File "/private/var/folders/hp/_4p52dfd7s9cf49p86sg1l_w0000gp/T/pip-install-yjxema7x/lxml/buildlibxml.py", line 291, in download_library
urlretrieve(full_url, dest_filename)
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 247, in urlretrieve
with contextlib.closing(urlopen(url, data)) as fp:
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 222, in urlopen
return opener.open(url, data, timeout)
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 525, in open
response = self._open(req, data)
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 543, in _open
'_open', req)
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 503, in _call_chain
result = func(*args)
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 1551, in ftp_open
raise exc.with_traceback(sys.exc_info()[2])
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 1540, in ftp_open
fp, retrlen = fw.retrfile(file, type)
File "/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/urllib/request.py", line 2419, in retrfile
raise URLError('ftp error: %r' % reason) from reason
urllib.error.URLError: <urlopen error ftp error: URLError("ftp error: error_perm('550 Failed to change directory.')")>
----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /private/var/folders/hp/_4p52dfd7s9cf49p86sg1l_w0000gp/T/pip-install-yjxema7x/lxml/
As the command failed on Downloading libxslt into libs/libxslt-1.1.33.tar.gz from ftp://xmlsoft.org/libxml2/libxslt-1.1.33.tar.gz
I browsed the ftp://xmlsoft.org/libxml2/ site which doesn't have ftp://xmlsoft.org/libxml2/libxslt-1.1.33.tar.gz, only ftp://xmlsoft.org/libxml2/libxslt-1.1.33-rc1.tar.gz.
Is this the problem, and if so is there a way to override it in the package? Or am I missing something?

Answer 1

You can bypass FTP errors while still having the STATIC_DEPS functionality by downloading libxml2 and libxslt manually and building from setup.py.
Pasted from the lxml website:
...If you want to use
specific versions, or want to prevent any online access, you can
download both tar.gz release files yourself, place them into a
subdirectory libs in the lxml distribution, and call setup.py with the
desired target versions like this:
python setup.py build --static-deps \
--libxml2-version=2.9.1 \
--libxslt-version=1.1.28 \
sudo python setup.py install