如何解决feign调用中文参数被encode编译的问题

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Feign调用中文参数被encode编译

原因

在实现一个feign调用时使用了Post请求，并且拼接url参数，name传值为中文时被encode转译，且最终接取数据之前未被decode转译回，问题探索：

feign：

@FeignClient(name = "service-test")public interface TestServiceApi {    @PostMapping("/test/abc")    public String getTestNo(@RequestParam("code") String code, @RequestParam("name") String name);}

controller：

@RequestMapping("/test")public interface TestController {    @Autowired    private TestService testService;    @PostMapping("/abc")    public String getTestNo(@RequestParam("code") String code, @RequestParam("name") String name) {        return testService.query(code, name);     }    }

在controller中接到的中文参数被URIEncode转译了

测试 被转译成：%E6%B5%8B%E8%AF%95

找到feign的入口类ReflectiveFeign中拼装RequestTemplate的方法：

    @Override    public RequestTemplate create(Object[] argv) {      RequestTemplate mutable = new RequestTemplate(metadata.template());      if (metadata.urlIndex() != null) {        int urlIndex = metadata.urlIndex();        checkArgument(argv[urlIndex] != null, "URI parameter %s was null", urlIndex);        mutable.insert(0, String.valueOf(argv[urlIndex]));      }      Map varBuilder = new LinkedHashMap();      for (Entry> entry : metadata.indexToName().entrySet()) {        int i = entry.getKey();        Object value = argv[entry.getKey()];        if (value != null) { // Null values are skipped.          if (indexToExpander.containsKey(i)) {            value = expandElements(indexToExpander.get(i), value);          }          for (String name : entry.getValue()) {            varBuilder.put(name, value);          }        }      }      // 组装template的方法      RequestTemplate template = resolve(argv, mutable, varBuilder);      if (metadata.queryMapIndex() != null) {        // add query map parameters after initial resolve so that they take        // precedence over any predefined values        template = addQueryMapQueryParameters(argv, template);      }      if (metadata.headerMapIndex() != null) {        template = addHeaderMapHeaders(argv, template);      }      return template;    }

在RequestTemplate类中如果是拼接在url后的param那么会被使用encodeValueIfNotEncoded都encode转译，但是不会走decode的方法

 /**   * Resolves any template parameters in the requests path, query, or headers against the supplied   * unencoded arguments. 
 

relationship to JAXRS 2.0
 
 This call is   * similar to {@code javax.ws.rs.client.WebTarget.resolveTemplates(templateValues, true)} , except   * that the template values apply to any part of the request, not just the URL   */  RequestTemplate resolve(Map unencoded, Map alreadyEncoded) {    replaceQueryValues(unencoded, alreadyEncoded);    Map encoded = new LinkedHashMap();    for (Entry entry : unencoded.entrySet()) {      final String key = entry.getKey();      final Object objectValue = entry.getValue();      String encodedValue = encodeValueIfNotEncoded(key, objectValue, alreadyEncoded);      encoded.put(key, encodedValue);    }    String resolvedUrl = expand(url.toString(), encoded).replace("+", "%20");    if (decodeSlash) {      resolvedUrl = resolvedUrl.replace("%2F", "/");    }    url = new StringBuilder(resolvedUrl);    Map> resolvedHeaders = new LinkedHashMap>();    for (String field : headers.keySet()) {      Collection resolvedValues = new ArrayList();      for (String value : valuesOrEmpty(headers, field)) {        String resolved = expand(value, unencoded);        resolvedValues.add(resolved);      }      resolvedHeaders.put(field, resolvedValues);    }    headers.clear();    headers.putAll(resolvedHeaders);    if (bodyTemplate != null) {      body(urlDecode(expand(bodyTemplate, encoded)));    }    return this;  }

如果传入的值在requestBody中，则不会被encode转译

    @Override    public void encode(Object requestBody, Type bodyType, RequestTemplate request)            throws EncodeException {        // template.body(conversionService.convert(object, String.class));        if (requestBody != null) {            Class requestType = requestBody.getClass();            Collection contentTypes = request.headers().get("Content-Type");            MediaType requestContentType = null;            if (contentTypes != null && !contentTypes.isEmpty()) {                String type = contentTypes.iterator().next();                requestContentType = MediaType.valueOf(type);            }            for (HttpMessageConverter messageConverter : this.messageConverters                    .getObject().getConverters()) {                if (messageConverter.canWrite(requestType, requestContentType)) {                    if (log.isDebugEnabled()) {                        if (requestContentType != null) {                            log.debug("Writing [" + requestBody + "] as \""                                    + requestContentType + "\" using ["                                    + messageConverter + "]");                        }                        else {                            log.debug("Writing [" + requestBody + "] using ["                                    + messageConverter + "]");                        }                    }                    FeignOutputMessage outputMessage = new FeignOutputMessage(request);                    try {                        @SuppressWarnings("unchecked")                        HttpMessageConverter