python/proton/_common.py

#
# Licensed to the Apache Software Foundation (ASF) under one
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# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
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# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
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from typing import Optional, Union, Any


def isinteger(value: Any) -> bool:
    return isinstance(value, int)


def isstring(value: Any) -> bool:
    return isinstance(value, str)


class Constant(object):

    def __init__(self, name: str) -> None:
        self.name = name

    def __repr__(self) -> str:
        return self.name


def secs2millis(secs: Union[float, int]) -> int:
    return int(secs * 1000)


def millis2secs(millis: int) -> float:
    return float(millis) / 1000.0


def unicode2utf8(string: Optional[str]) -> Optional[str]:
    """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):
        # The swig binding converts py3 str -> utf8 char* and back automatically
        return string
    # Anything else illegal - specifically python3 bytes
    raise TypeError("Unrecognized string type: %r (%s)" % (string, type(string)))


def utf82unicode(string: Optional[Union[str, bytes]]) -> Optional[str]:
    """Convert C strings returned from proton-c into python unicode"""
    if string is None:
        return None
    elif isinstance(string, str):
        return string
    elif isinstance(string, bytes):
        return string.decode('utf8')
    raise TypeError("Unrecognized string type")