Collect single S3 artifact
         :param: path string: S3 path

def collect_single_s3(self, path):
        """ Collect single S3 artifact
         :param: path string: S3 path
        """

        # The S3 folder contains the tokens needed to perform
        # matching of project, gitref, etc.
        folder = os.path.dirname(path)

        rinfo = re.findall(r'(?P<tag>[^-]+)-(?P<val>.*?)__', folder)
        if rinfo is None or len(rinfo) == 0:
            # print('Incorrect folder/file name format for %s' % folder)
            return None

        info = dict(rinfo)

        # Ignore AppVeyor Debug builds
        if info.get('bldtype', '').lower() == 'debug':
            print('Ignoring debug artifact %s' % folder)
            return None

        tag = info.get('tag', None)
        if tag is not None and (len(tag) == 0 or tag.startswith('$(')):
            # AppVeyor doesn't substite $(APPVEYOR_REPO_TAG_NAME)
            # with an empty value when not set, it leaves that token
            # in the string - so translate that to no tag.
            tag = None

        sha = info.get('sha', None)

        # Match tag or sha to gitref
        if (tag is not None and tag == self.gitref) or (sha is not None and sha.startswith(self.gitref)):
            return Artifact(self, path, info)

        return None