private ShenYuResult assertAndGet(final ResponseEntity<ShenYuResult> response, final String message) {
        Assertions.assertEquals(HttpStatus.OK, response.getStatusCode(), "checking http status");

        ShenYuResult rst = response.getBody();
        Assertions.assertNotNull(rst, "checking http response body");
        Assertions.assertEquals(200, rst.getCode(), "checking shenyu result code");
        Assertions.assertEquals(message, rst.getMessage(), "checking shenyu result message");

        return rst;
    }
Fetch Selector by given id.

@param id of selector that needs to fetch
@return {@link SelectorDTO}
shenyu-e2e/shenyu-e2e-client/src/main/java/org/apache/shenyu/e2e/client/admin/AdminClient.java