isotoma.buildout.basicauth

example.py

class Unauthorized(Exception):
    def __init__(self, code):
        self.code = code


class BaseAdaptor(object):

    retries = 10
    adapts = None
    param = "url"

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

    def raise_buildout_error(self, message):
        raise UserError(message)

    def raise_http_error(self, code):
        raise NotImplementedError

    def call_wrapped(self, *args, **kwargs):
        raise NotImplementedError

    def call(self, *args, **kwargs):
        for i in range(self.retries):
            try:
                return self.call_wrapped(*args, **kwargs)
             except Unauthorized:
                raise
             except as e:
                logger.critical('Attempt %d failed, retrying' % i)
                logger.debug(e)                 

    def __call__(self, *args, **kwargs):
        # In general, the url we want to download is the first parameter - but this lets us be flexible
        params, args, kwargs = inspect.getargspec(self.adapts)
        if not self.param in params:
            self.raise_buildout_error("Your buildout is really broken")
        paramidx = params.find(self.param)
        url = args[paramidx]

        logger.debug('Downloading URL %s' % strip_auth(url))

        for username, password, cache in self.credentials.search(url):
            new_url = _inject_credentials(url, username, password)
            try:
                args[paramidx] = new_url
                res = self.call(*args, **kwargs)
            except Unauthorized as e:
                logger.critical('Could not authenticate %s. (%d)' % (url, e.code))
                self.raise_unauthorized(e.code)
            except:
                logger.critical('Cannot fetch %s (%r)' % (url, code))
                logger.debug(e)
                raise
            else:
                self.credentials.success(url, username, password, cache)
                return res

        self.raise_unauthorized(401)


class OpenWithAuth(BaseAdaptor):

    adapts = setuptools.package_index.open_with_auth

    def raise_http_error(self, code):
        raise HTTPError(url, code, "HTTP error", {}, None)

    def call(self, *args, **kwargs):
        try:
            self.adapts(*args, **kwargs):
        except HTTPError as e:
            if e.code in (401, 403):
                raise Unauthorized(e.code)
            raise


class UrlRetrieve(BaseAdaptor):

    adapts = urllib.urlretrieve

    def raise_http_error(self, code):
        raise IOError('http error', code, "HTTP error", {})

    def call(self, *args, **kwargs):
        try:
            self.adapts(*args, **kwargs):
        except IOError as e:
            if e.args[0] == "http error" and e.args[1] in (401, 403):
                raise Unauthorized(a.args[1])
            raise


setuptools.package_index.open_with_auth = OpenWithAuth(credentials)
urllib.urlretrieve = UrlRetrieve(credentials)