example

class HandleEvent(testtools.StreamResult):
    def __init__(self, callback):
        self._buffers = {}
        self._callback = callback
    
    def status(self, test_id=None, test_status=None, test_tags=None,
            runnable=True, file_name=None, file_bytes=None, eof=False,
            mime_type=None, route_code=None, timestamp=None):
        if not test_id:
            return
        if file_name != "collect.json":
            return
        key = (route_code, file_name)
        segments = self._buffers.pop(key, [])
        segments.append(file_bytes)
        if eof:
            content = b''.join(segments)
            self._callback(content)
            return
        self._buffers[key] = segments

    def stopTestRun(self):
        for segments in self._buffers.values():
            self._callback(b''.join(segments))