我正在使用 Spring Boot，并且我想为一些 RequestMapping 添加 API 版本控制支持（url 路径应该以 /v[1-9]+/ 开头）。
我正在考虑创建一个注释：MyRequestMapping，它还支持 api 版本控制路径。这样，任何使用 MyRequestMapping 的人都会自动分配给它的 api 版本。
由于我无法扩展 RequestMapping 注释（Java 中不允许注释扩展），我不确定如何继续使用这种方法。任何提示/想法都会很棒！
简而言之：我如何支持 RequestMapping 中“路径”的 api 版本控制？谢谢..
我将创建与以 /v[1-9]+/ 开头的 URL 匹配的纯类 MyRequestMapping
有关在请求映射中使用正则表达式的官方文档，请参阅https://docs.spring.io/spring/docs/current/spring-framework-reference/web.html#mvc-ann-requestmapping-uri-templates
然后用户可以使用方法级别的 RequestMapping 注释进一步缩小路径。
我找到了支持 api 版本控制的更好方法。下面是解释：
1）创建注解：ApiVersion：
@Target({ ElementType.METHOD, ElementType.TYPE })
@Retention(RetentionPolicy.RUNTIME)
@Documented
@RequestMapping("/{apiVersion}")
public @interface ApiVersion {
/**
* version
*
* @return
*/
int value() default 1;
boolean latest() default false;
}
2）创建自定义RequestCondition来放置匹配逻辑：**
公共类 ApiVersionCondition 实现 RequestCondition {
private final static Pattern VERSION_PREFIX_PATTERN = Pattern.compile("/v(\\d+)/");
private final static Pattern LATEST_PREFIX_PATTERN = Pattern.compile("/latest/");
private int apiVersion;
private boolean latest;
public ApiVersionCondition(int apiVersion, boolean latest) {
this.apiVersion = apiVersion;
this.latest = latest;
}
/**
* Latest definition will take effect, that means method definition will override the classes definition
*
* @param otherApiVersionCondition other condition that is matching.
* @return latest definition of matching condition.
*/
public ApiVersionCondition combine(ApiVersionCondition otherApiVersionCondition) {
return new ApiVersionCondition(otherApiVersionCondition.getApiVersion(), otherApiVersionCondition.isLatest());
}
/**
* Define matcher to match the pattern for api versioning.
* When version number requested is equal to or greater than configured, condition will be returned.
*
* @param request Request instance
* @return ApiVersionCondition based on match
*/
public ApiVersionCondition getMatchingCondition(HttpServletRequest request) {
Matcher m = LATEST_PREFIX_PATTERN.matcher(request.getRequestURI());
if (m.find() && isLatest()) {
return this;
}
m = VERSION_PREFIX_PATTERN.matcher(request.getRequestURI());
if (m.find()) {
Integer version = Integer.valueOf(m.group(1));
if (version >= this.apiVersion)
return this;
}
return null;
}
/**
* When more than one configured version number passes the match rule, the bigest one will take effect.
*
* @param otherApiVersionCondition other api version condition that was satisfied.
* @param request Request instance
* @return 1 if other version condition has greater api version, -1 if this condition has greater api version, 0 if they are same.
*/
public int compareTo(ApiVersionCondition otherApiVersionCondition, HttpServletRequest request) {
return otherApiVersionCondition.getApiVersion() - this.apiVersion;
}
/**
* Getter for api version.
*
* @return api version for the condition.
*/
private int getApiVersion() {
return apiVersion;
}
/**
* Getter for whether latest is configured in annotation.
*
* @return true if latest is configured in annotation, else false.
*/
private boolean isLatest() {
return latest;
}
}
3）创建自定义RequestMappingHandlerMapping：
public class ApiVersioningRequestMappingHandlerMapping extends RequestMappingHandlerMapping {
@Override
protected RequestCondition<ApiVersionCondition> getCustomTypeCondition(Class<?> handlerType) {
return createCondition(AnnotationUtils.findAnnotation(handlerType, ApiVersion.class));
}
@Override
protected RequestCondition<ApiVersionCondition> getCustomMethodCondition(Method method) {
return createCondition(AnnotationUtils.findAnnotation(method, ApiVersion.class));
}
private RequestCondition<ApiVersionCondition> createCondition(ApiVersion apiVersion) {
return apiVersion == null ? null : new ApiVersionCondition(apiVersion.value(), apiVersion.latest());
}
}
4）让Spring使用自定义的RequestMappingHandlerMapping：
@Configuration
public class WebMvcRegistrationsConfig implements WebMvcRegistrations {
@Override
public RequestMappingHandlerMapping getRequestMappingHandlerMapping() {
ApiVersioningRequestMappingHandlerMapping apiVersioningRequestMappingHandlerMapping = new ApiVersioningRequestMappingHandlerMapping();
apiVersioningRequestMappingHandlerMapping.setOrder(0);
apiVersioningRequestMappingHandlerMapping.setRemoveSemicolonContent(false);
return apiVersioningRequestMappingHandlerMapping;
}
}
5）在控制器中使用它：
@ApiVersion //default is version 1
//@RequestMapping("{apiVersion}/test") //add this if want to specify a common root e.g. v<x>/test for all below request mapping
@RestController
public class GreetingController {
private static final String template = "Hello , %s!";
private final AtomicLong counter = new AtomicLong();
@RequestMapping("/greeting") // URI: /v1/greeting will be mapped to this method
public Greeting greeting(@RequestParam(value = "name", defaultValue = "World") String name) {
return new Greeting(counter.incrementAndGet(),
String.format(template, name));
}
@ApiVersion(2)
@RequestMapping("/greeting") // URI: /v2/greeting will be mapped to this method
public Greeting greetingV2(@RequestParam(value = "name", defaultValue = "World version 2") String name) {
return new Greeting(counter.incrementAndGet(),
String.format(template, name));
}
@ApiVersion(value = 3, latest = true)
@RequestMapping("/greeting") // URI: /v3/greeting OR /latest/greeting will be mapped to this method
public Greeting greetingV3(@RequestParam(value = "name", defaultValue = "World version 3") String name) {
return new Greeting(counter.incrementAndGet(),
String.format(template, name));
}
}
还有一些微调要做，但这是我想要实现的一个好的开始。如果找到更好的想法或一些改进，将更新。如果有人发现改进，请告诉我们。
您可以使用filter, 并在内部进行所需的检查filter。如果检查没有返回 true，只需httpresponse从过滤器本身修改并返回，就是这样。我在下面添加了一个示例filter，您需要相应地在web.xml或@configuration类中进行必要的更改，才能使过滤器正常工作。
public class MyFilter implements Filter {
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
throws IOException, ServletException {
if("")//Do the required check here
{
//Modifiy httpservlet response .
}
filterChain.doFilter(servletRequest, servletResponse);
}
}