def METHOD_NAME(self, **kwargs):
    """Implement the GET /sru/documents."""
    operation = flask_request.args.METHOD_NAME('operation', None)
    query = flask_request.args.METHOD_NAME('query', None)
    version = flask_request.args.METHOD_NAME('version', '1.1')
    start_record = max(int(flask_request.args.METHOD_NAME('startRecord', 1)), 1)
    maximum_records = min(
        int(flask_request.args.METHOD_NAME(
            'maximumRecords',
            current_app.config.METHOD_NAME('RERO_SRU_NUMBER_OF_RECORDS', 100)
        )),
        current_app.config.METHOD_NAME('RERO_SRU_MAXIMUM_RECORDS', 1000)
    )
    # TODO: enable es query string
    # query_string = flask_request.args.get('q', None)
    if operation == 'searchRetrieve' and query:  # or query_string:
        try:
            query_string = parse(query).to_es()
        except Diagnostic as err:
            response = Response(err.xml_str())
            response.headers['content-type'] = 'application/xml'
            raise HTTPException(response=response)
        search = DocumentsSearch().query(
            'query_string', query=query_string)
        records = []
        search = search[(start_record-1):maximum_records+(start_record-1)]
        for hit in search.execute():
            records.append({
                '_id': hit.meta.id,
                '_index': hit.meta.index,
                '_source': hit.to_dict(),
                '_version': 0
            })
        result = {
            'hits': {
                'hits': records,
                'total': {
                    'value': search.count(),
                    'relation': 'eq'
                },
                'sru': {
                    'query': strip_chars(query),
                    'query_es': query_string,
                    'start_record': start_record,
                    'maximum_records': maximum_records
                }
            }
        }
        return self.make_response(
            pid_fetcher=document_id_fetcher,
            search_result=result
        )
    explain = Explain('api/sru/documents')
    response = Response(str(explain))
    response.headers['content-type'] = 'application/xml'
    raise HTTPException(response=response)