Canary deploys with spring-cloud-gateway (2.0.0-M1)

SpringCloudGatewayApplication.java

@EnableGateway
@SpringBootApplication
public class SpringCloudGatewayApplication {

    private final String cookieName = "beta_active";
    private final String headerName = "X-Beta-active";
    private final String betaActiveValue = "true";

    /**
     * They're in the beta if they have a cookie or request header set
     */
    private final Predicate<ServerWebExchange> ifBetaActive = serverWebExchange -> {
        HttpCookie cookie = serverWebExchange.getRequest().getCookies().getFirst(cookieName);
        if (cookie != null && Objects.equals(cookie.getValue(), betaActiveValue)) {
            return true;
        }
        List<String> values = serverWebExchange.getRequest().getHeaders().get(headerName);
        return values != null && values.contains(betaActiveValue);
    };

    /**
     * 10% chance that we'll enroll them in the beta
     */
    private final Predicate<ServerWebExchange> randomBetaEnroll = serverWebExchange -> Math.random() < 0.2;


    /**
     * this always returns true
     */
    private final Predicate<ServerWebExchange> always = (x) -> true;


    /**
     * Adds a cookie to the response so they stay in the beta
     */
    private final WebFilter addBetaCookieFilter = (ServerWebExchange exchange, WebFilterChain chain) -> {
        exchange.getResponse().addCookie(ResponseCookie.from(cookieName, betaActiveValue).maxAge(Duration.ofHours(4)).httpOnly(true).build());
        return chain.filter(exchange);
    };

    public static void main(String[] args) {
        SpringApplication.run(SpringCloudGatewayApplication.class, args);
    }

    @Bean
    public RouteLocator routes() {
        return Routes.locator()
                .route("new-service")
                .uri("http://localhost:9002")
                .predicate(ifBetaActive.or(randomBetaEnroll))
                .add(addBetaCookieFilter)
                .and()
                .route("old-service")
                .uri("http://localhost:9001")
                .predicate(always)
                .and()
                .build();
    }


}