Source code for rosdistro.loader

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# Copyright (c) 2013, Open Source Robotics Foundation, Inc.
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import socket
import time
try:
    from urllib.request import urlopen
    from urllib.error import HTTPError
    from urllib.error import URLError
except ImportError:
    from urllib2 import urlopen
    from urllib2 import HTTPError
    from urllib2 import URLError


def load_url(url, retry=2, retry_period=1, timeout=10, skip_decode=False):
    try:
        fh = urlopen(url, timeout=timeout)
    except HTTPError as e:
        if e.code in [500, 502, 503] and retry:
            time.sleep(retry_period)
            return load_url(url, retry=retry - 1, retry_period=retry_period, timeout=timeout)
        e.msg += ' (%s)' % url
        raise
    except URLError as e:
        if isinstance(e.reason, socket.timeout) and retry:
            time.sleep(retry_period)
            return load_url(url, retry=retry - 1, retry_period=retry_period, timeout=timeout)
        raise URLError(str(e) + ' (%s)' % url)
    except socket.timeout as e:
        raise socket.timeout(str(e) + ' (%s)' % url)
    # Python 2/3 Compatibility
    contents = fh.read()
    if isinstance(contents, str) or skip_decode:
        return contents
    else:
        return contents.decode('utf-8')