Webflux Spring 2.1.2自定义内容类型

我正试图通过WebClient发布以获取microsoft令牌：

public WebClient getWebclient() {
    TcpClient client = TcpClient.create()
            .option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 10000)
            .doOnConnected(connection -> connection.addHandlerLast(new ReadTimeoutHandler(15)).addHandlerLast(new WriteTimeoutHandler(15)));

    ExchangeStrategies strategies = ExchangeStrategies.builder()
            .codecs(configurer -> {
                configurer.registerDefaults(true);
                FormHttpMessageReader formHttpMessageReader = new FormHttpMessageReader();
                formHttpMessageReader.setEnableLoggingRequestDetails(true);
                configurer.customCodecs().reader(formHttpMessageReader);
            })
            .build();

    return WebClient.builder()
            .clientConnector(new ReactorClientHttpConnector(HttpClient.from(client).followRedirect(true)))
            .exchangeStrategies(strategies)
            .filter(logRequest())
            .filter(logResponse())
            .build();
}

MultiValueMap<String, String> credentials = new LinkedMultiValueMap<>();
        credentials.add("grant_type", "password");
        credentials.add("client_id", oauthClientId);
        credentials.add("resource", oauthResource);
        credentials.add("scope", oauthScope);
        credentials.add("username", oauthUsername);
        credentials.add("password", oauthPassword);

        Mono<MicrosoftToken> response = webClientService.getWebclient().post()
                .uri(oauthUrl)
                .contentType(MediaType.APPLICATION_FORM_URLENCODED)
                .body(BodyInserters.fromFormData(credentials))
                .retrieve()
                .onStatus(HttpStatus::is4xxClientError, clientResponse ->
                        Mono.error(new WebClientException(clientResponse.bodyToMono(String.class), clientResponse.statusCode())))
                .bodyToMono(MicrosoftToken.class);

        this.cachedToken = response.block();

我用spring版本2.0.0对此进行了测试，在新版本中没有添加字符集：

POST /common/oauth2/token HTTP/1.1
user-agent: ReactorNetty/0.7.5.RELEASE
host: login.microsoftonline.de
accept-encoding: gzip
Content-Type: application/x-www-form-urlencoded
Content-Length: 205

---

这里有两种方法：

webClient
   .mutate()
   .defaultHeaders(headers -> {
      headers.add("Content-Type", ContentType.APPLICATION_FORM_URLENCODED.getMimeType()
   }).build()
   . uri(uri)
   ...

OR 

webClient
   .post()
   .uri(uri)
   .body(body)
   .headers(headers -> getHttpHeaders())
   ...

private HttpHeaders getHttpHeaders(){
   HttpHeaders headers = new HttpHeaders();
   headers.add("Content-Type", "application/x-www-form-urlencoded")
   return headers;
}

只有几种方法可以利用.headers或.defaultHeaders中的headers消费者

但老实说，我不认为字符集是个问题。如果您在响应中获得application/json，可能是因为Microsoft正在通过您在应用程序注册中指定的重定向url转发带有该标题的请求

好消息是这可能是可取的，因为Microsoft将令牌字段返回为json，这允许您调用.bodyTomino（MicrosoftToken）。我记得BodyInserters.fromFormData存在问题，因为它实际上没有对多值映射中的值进行编码

这就是我正在使用的：

    private BodyInserter<String, ReactiveHttpOutputMessage> getBodyInserter(Map<String,String> parameters) {

        credentials.add("grant_type", encode("password"));
        credentials.add("client_id", encode(oauthClientId));
        credentials.add("resource", encode(oauthResource));
        // and so on..
        // note that parameters is a regular Map - not a MultiValueMap

        BodyInserter<String, ReactiveHttpOutputMessage> bodyInserter = BodyInserters.fromObject(
                parameters.entrySet().stream()
                        .map(entry -> entry.getKey().concat("=").concat(entry.getValue()))
                        .collect(Collectors.joining("&", "", "")));

        return bodyInserter;
    }

    private String encode(String str) {
        try {
            return URLEncoder.encode(str, StandardCharsets.UTF_8.name());
        } catch (UnsupportedEncodingException e) {
            log.error("Error encoding req body", e);
        }
    }

private BodyInserter getBodyInserter（映射参数）{
添加（“授权类型”，编码（“密码”）；
添加（“客户端id”，编码（oauthClientId））；
添加（“资源”，编码（oauthResource））；
//等等。。
//请注意，参数是常规映射，而不是多值映射
BodyInserter BodyInserter=BodyInserters.fromObject(
parameters.entrySet（）.stream（）
.map（entry->entry.getKey（）.concat（“=”）.concat（entry.getValue（））
.collect（收集器.加入（&），“”，“”）；
回体插入器；
}
私有字符串编码（字符串str）{
试一试{
返回URLEncoder.encode（str，StandardCharsets.UTF_8.name（））；
}捕获（不支持的编码异常e）{
log.error（“错误编码请求体”，e）；
}
}

我花了一上午最长的时间才找到答案，但我最终还是成功了。问题是Webflux

BodyInserters.fromFormData

总是将内容类型设置为

application/x-www-form-urlencoded；charset=…

无论您在标题中设置了什么

要解决此问题，请首先定义此方法：

/**
 * This method is unfortunately necessary because of Spring Webflux's propensity to add {@code ";charset=..."}
 * to the {@code Content-Type} header, which the Generic Chinese Device doesn't handle properly.
 *
 * @return a {@link FormInserter} that doesn't add the character set to the content type header
 */
private FormInserter<String> formInserter() {

    return new FormInserter<String>() {

        private final MultiValueMap<String, String> data = new LinkedMultiValueMap<>();

        @Override public FormInserter<String> with(final String key, final String value) {
            data.add(key, value);
            return this;
        }

        @Override public FormInserter<String> with(final MultiValueMap<String, String> values) {
            data.addAll(values);
            return this;
        }

        @Override public Mono<Void> insert(final ClientHttpRequest outputMessage, final Context context) {
            final ResolvableType formDataType =
                    ResolvableType.forClassWithGenerics(MultiValueMap.class, String.class, String.class);
            return new FormHttpMessageWriter() {
                @Override protected MediaType getMediaType(final MediaType mediaType) {
                    if (MediaType.APPLICATION_FORM_URLENCODED.equals(mediaType)) {
                        return mediaType;
                    } else {
                        return super.getMediaType(mediaType);
                    }
                }
            }.write(Mono.just(this.data), formDataType,
                    MediaType.APPLICATION_FORM_URLENCODED,
                    outputMessage,
                    context.hints());
        }
    };
}

---

请注意，上面的方框主要用于演示目的。您可能希望也可能不希望阻止并等待响应。

在使用WebClient发送请求时，您是否尝试过设置内容类型？你能显示一个实际发送请求的代码段吗？是的，我试过了，正在设置内容类型。但是Spring稍后将覆盖内容类型，或者更确切地说是将字符集添加到已设置的内容类型。请检查我的答案以获得正确的解决方案。谢谢分享！也解决了这个问题。

/**
 * This method is unfortunately necessary because of Spring Webflux's propensity to add {@code ";charset=..."}
 * to the {@code Content-Type} header, which the Generic Chinese Device doesn't handle properly.
 *
 * @return a {@link FormInserter} that doesn't add the character set to the content type header
 */
private FormInserter<String> formInserter() {

    return new FormInserter<String>() {

        private final MultiValueMap<String, String> data = new LinkedMultiValueMap<>();

        @Override public FormInserter<String> with(final String key, final String value) {
            data.add(key, value);
            return this;
        }

        @Override public FormInserter<String> with(final MultiValueMap<String, String> values) {
            data.addAll(values);
            return this;
        }

        @Override public Mono<Void> insert(final ClientHttpRequest outputMessage, final Context context) {
            final ResolvableType formDataType =
                    ResolvableType.forClassWithGenerics(MultiValueMap.class, String.class, String.class);
            return new FormHttpMessageWriter() {
                @Override protected MediaType getMediaType(final MediaType mediaType) {
                    if (MediaType.APPLICATION_FORM_URLENCODED.equals(mediaType)) {
                        return mediaType;
                    } else {
                        return super.getMediaType(mediaType);
                    }
                }
            }.write(Mono.just(this.data), formDataType,
                    MediaType.APPLICATION_FORM_URLENCODED,
                    outputMessage,
                    context.hints());
        }
    };
}

final SomeResponseObject response = WebClient
        .builder()
        .build()
        .post()
        .uri(someOrOtherUri)
        .body(formInserter().with("param1", "value1")
                            .with("param2", "value2")
        )
        .retrieve()
        .bodyToFlux(SomeReponseObject.class)
        .blockLast();