python/proton/_common.py

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# to you under the Apache License, Version 2.0 (the
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#
#   http://www.apache.org/licenses/LICENSE-2.0
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# KIND, either express or implied.  See the License for the
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# under the License.
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#
# Hacks to provide Python2 <---> Python3 compatibility
#
# The results are
# |       |long|unicode|
# |python2|long|unicode|
# |python3| int|    str|
try:
    long()
except NameError:
    long = int
try:
    unicode()
except NameError:
    unicode = str


def isinteger(value):
    return isinstance(value, (int, long))


def isstring(value):
    return isinstance(value, (str, unicode))


class Constant(object):

    def __init__(self, name):
        self.name = name

    def __repr__(self):
        return self.name


def secs2millis(secs):
    return long(secs * 1000)


def millis2secs(millis):
    return float(millis) / 1000.0


def unicode2utf8(string):
    """Some Proton APIs expect a null terminated string. Convert python text
    types to UTF8 to avoid zero bytes introduced by other multi-byte encodings.
    This method will throw if the string cannot be converted.
    """
    if string is None:
        return None
    elif isinstance(string, str):
        # Must be py2 or py3 str
        # The swig binding converts py3 str -> utf8 char* and back sutomatically
        return string
    elif isinstance(string, unicode):
        # This must be python2 unicode as we already detected py3 str above
        return string.encode('utf-8')
    # Anything else illegal - specifically python3 bytes
    raise TypeError("Unrecognized string type: %r (%s)" % (string, type(string)))


def utf82unicode(string):
    """Convert C strings returned from proton-c into python unicode"""
    if string is None:
        return None
    elif isinstance(string, unicode):
        # py2 unicode, py3 str (via hack definition)
        return string
    elif isinstance(string, bytes):
        # py2 str (via hack definition), py3 bytes
        return string.decode('utf8')
    raise TypeError("Unrecognized string type")