# Buggy code
def open(uri, mode, min_part_size=WEBHDFS_MIN_PART_SIZE):
    """
    Parameters
    ----------
    min_part_size: int, optional
        For writing only.

    """
    if mode == "rb":
        return BufferedInputBase(uri)
    elif mode == "wb":
        return BufferedOutputBase(uri, min_part_size=min_part_size)
    else:
        raise NotImplementedError("webhdfs support for mode %r not implemented" % mode)


# Traceback (TypeError)
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-40-b63bd711d13c> in <module>
----> 1 smart_copy('./test_file.txt', 'webhdfs://XXXX@XXX.XXX.XXX.XXX:XXXXX/user/XXXX/smart_copy/test_file.txt')

<ipython-input-38-694f70cf0776> in smart_copy(source_file, sync_file)
3     '''
4     with open(source_file, 'rb') as source:
----> 5         with open(sync_file, 'wb') as sync:
6             for line in source:
7                 sync.write(line)

~/Github/tools/.venv/lib/python3.7/site-packages/smart_open/smart_open_lib.py in open(uri, mode, buffering, encoding, errors, newline, closefd, opener, ignore_ext, transport_params)
346     except KeyError:
347         binary_mode = mode
--> 348     binary, filename = _open_binary_stream(uri, binary_mode, transport_params)
349     if ignore_ext:
350         decompressed = binary

~/Github/tools/.venv/lib/python3.7/site-packages/smart_open/smart_open_lib.py in _open_binary_stream(uri, mode, transport_params)
560         elif parsed_uri.scheme == "webhdfs":
561             kw = _check_kwargs(smart_open_webhdfs.open, transport_params)
--> 562             return smart_open_webhdfs.open(parsed_uri.uri_path, mode, **kw), filename
563         elif parsed_uri.scheme.startswith('http'):
564             #

~/Github/tools/.venv/lib/python3.7/site-packages/smart_open/webhdfs.py in open(uri, mode, min_part_size)
40         return BufferedInputBase(uri)
41     elif mode == 'wb':
---> 42         return BufferedOutputBase(uri, min_part_size=min_part_size)
43     else:
44         raise NotImplementedError('webhdfs support for mode %r not implemented' % mode)

~/Github/tools/.venv/lib/python3.7/site-packages/smart_open/webhdfs.py in __init__(self, uri_path, min_part_size)
129                                      params=payload, allow_redirects=False)
130         if not init_response.status_code == httplib.TEMPORARY_REDIRECT:
--> 131             raise WebHdfsException(str(init_response.status_code) + "\n" + init_response.content)
132         uri = init_response.headers['location']
133         response = requests.put(uri, data="", headers={'content-type': 'application/octet-stream'})

TypeError: can only concatenate str (not "bytes") to str

# Fixed code
def open(http_uri, mode, min_part_size=WEBHDFS_MIN_PART_SIZE):
    """
    Parameters
    ----------
    http_uri: str
        webhdfs url converted to http REST url
    min_part_size: int, optional
        For writing only.

    """
    if mode == "rb":
        return BufferedInputBase(http_uri)
    elif mode == "wb":
        return BufferedOutputBase(http_uri, min_part_size=min_part_size)
    else:
        raise NotImplementedError("webhdfs support for mode %r not implemented" % mode)