client.py 文件源码

def _make_context_header(
        self,
        switches=None,
        correlation_id=None,
        context_extra=None,
    ):
        # Copy the underlying context object, if it was provided
        context = dict(self.context.items()) if self.context else {}
        # Either add on, reuse or generate a correlation ID
        if correlation_id is not None:
            context['correlation_id'] = correlation_id
        elif 'correlation_id' not in context:
            context['correlation_id'] = six.u(uuid.uuid1().hex)
        # Switches can come from three different places, so merge them
        # and ensure that they are unique
        switches = set(switches or [])
        if context_extra:
            switches |= set(context_extra.pop('switches', []))
        context['switches'] = list(set(context.get('switches', [])) | switches)
        # Add any extra stuff
        if context_extra:
            context.update(context_extra)
        return context