public static Builder builder() {
        return new Builder();
    }
@Test
    public void testEqualsAndHashCode() {
        WebSocketUpstream upstream1 = WebSocketUpstream.builder().protocol("protocol").upstreamUrl("url")
                .status(true).warmup(50).timestamp(1650549243L).build();
        WebSocketUpstream upstream2 = WebSocketUpstream.builder().protocol("protocol").upstreamUrl("url")
                .status(true).warmup(50).timestamp(1650549243L).build();
        
        assertThat(ImmutableSet.of(upstream1, upstream2), hasSize(1));
    }