Spring WebClient 使用新的重试逻辑 Headers

Question

我正在尝试使用 Spring WebClient 构建重试逻辑。我要解决的问题非常简单。我正在调用 API 端点来获取一些值。如果 API returns 出现 401 响应错误，那么我将不得不调用令牌服务并更新我的令牌并使用新令牌并进行相同的 API 调用。

一般psudo是

try {
    GET /locations data
} catch(401 Unauthorized) {
    POST /token and get renew Token --> This is another WebClient API call With New Token
    call again GET /locations and return value
} catch (Another Exception) {
    throw Application Error
}

这是我正在尝试执行的 Spring 代码，但它看起来无法正常工作。关于如何操作的任何建议。

public List<Location> getLocations(final User user) {
    if (null == user) {
        throw new ApplicationException("User cannot be null");
    }

    if (null == user.getHoneyWellLinkToken()) {
        throw new ApplicationException(String.format("%s has not linked the account with Honeywell", user.getUsername()));
    }


    List<Location> locations = getLocationsAPI(user).block();

    return locations;

}

private Mono<List<Location>> getLocationsAPI(final User user) {
    String endpoint = config.getApi().getLocationsEndpoint()
                .concat("?apikey=")
                .concat(config.getCredentials().getClientId());

    return WebClient.builder().baseUrl(endpoint)
                .build()
                .get()
                .headers(httpHeaders -> httpHeaders.setBearerAuth(user.getHoneyWellLinkToken().getAccessToken()))
                .retrieve()
                .bodyToFlux(Location.class)
                .collectList()
                .doOnError(err -> {
                    WebClient.builder().baseUrl(endpoint)
                            .build()
                            .get()
                            .headers(httpHeaders -> httpHeaders.setBearerAuth(honeywellService.renewToken(user).block().getHoneyWellLinkToken().getAccessToken()))
                            .retrieve().bodyToFlux(Location.class);

                });

}

此代码托管于 GitHub https://github.com/reflexdemon/home-use/blob/main/src/main/java/io/vpv/homeuse/service/HoneywellThermostatService.java

Answer 1

使用onErrorResume代替doOnError
更新令牌时不要block

    private Mono<List<Location>> getLocationsAPI(final User user) {
        String endpoint = config.getApi().getLocationsEndpoint()
                                .concat("?apikey=")
                                .concat(config.getCredentials().getClientId());

        return getLocations(endpoint, user)
            .onErrorResume(err -> honeywellService.renewToken(user)
                                                  .flatMap(newUser -> getLocations(endpoint, newUser)));

    }

    private Mono<List<Location>> getLocations(String endpoint, User user) {
        return WebClient.builder()
                        .baseUrl(endpoint)
                        .build()
                        .get()
                        .headers(httpHeaders -> httpHeaders.setBearerAuth(user
                            .getHoneyWellLinkToken()
                            .getAccessToken()))
                        .retrieve()
                        .bodyToFlux(Location.class)
                        .collectList();
    }

此外，使用单个 WebClient 实例而不是为每个请求构建一个新实例是个好主意。

Spring WebClient 使用新的重试逻辑 Headers

Spring WebClient Retry Logic with new Headers

java

spring

spring-boot

spring-webflux

spring-webclient