java – Spring REST重用嵌套的requstmapping

我们有一个REST API,用于一些评论.目前,最有趣的URI是：

GET /products/1/comments             // get all comments of product 1
GET /products/1/comments/5           // get the 5th comment of product 1
GET /products/1/comments/5/user      // get the user of the 5th comment
GET /products/1/comments/latest      // get the latest comment of product 1
GET /products/1/comments/latest/user // get the user of the latest comment

此外,您还可以直接访问评论

GET /comments/987                    // get the comment with id 987
GET /comments/987/user               // get the user of comment with id 987

所以,我们有两个@RestController：

@RestController
@RequestMapping("/products/{productId}")
public class ProductsCommentsResource {

    @GetMapping(value = "/comments")
    public ResponseEntity<?> getComments(@PathVariable Long productId){
       // get all products...
    }

    @GetMapping(value = "/comments/{commentNr}")
    public ResponseEntity<?> getComment(@PathVariable Long productId, @PathVaraible Long commentNr){
       // get comment with number commentNr of product productId
    }

    @GetMapping(value = "/comments/{commentNr}/user")
    public ResponseEntity<?> getCommentUser(@PathVariable Long productId, @PathVaraible Long commentNr){
       // get the user of comment with commentNr of productId
    }

    @GetMapping(value = "/comments/latest")
    public ResponseEntity<?> getLatestComment(@PathVariable Long productId){
       // get latest commentNr and call getComment(productId, commentNr)
    }

    @GetMapping(value = "/comments/latest/user")
    public ResponseEntity<?> getLatestCommentUser(@PathVariable Long productId){
       // get latest commentNr and call getCommentUser(productId, commentNr)
    }
}

@RestController
@RequestMapping("/comments")
public class CommentsResource {
    @GetMapping(value = "/{commentId}")
    public ResponseEntity<?> getComment(@PathVaraible Long commentId){
       // get comment id commentId
    }

    @GetMapping(value = "/{commentId}/user")
    public ResponseEntity<?> getCommentUser(@PathVaraible Long commendId){
       // get the user of comment with id commentId
    }
}      

因此,最新版本只是“获取最后一条注释并使用此commentId调用相应方法”的替换关键字

这只是一个摘录,除了用户之外,评论还有大约30个子资源和子资源(包括POST,DELETE等方法).
因此,我们或多或少都有三次.

所以,显然,我们需要改进这一点,删除重复的代码等.
我们的想法是“封装”评论资源,并通过使用在类中注释的@RequestMapping使其可重用.

我们考虑过像以下一样的机制：

>调用/ products / 1 / comments / latest / user
>呼叫被拦截,产品1的“最新”被解析为commentId
>调用将重定向到“/ comments / {commendId} / user

因此,我们需要有重定向的东西
  – / products / 1 / comments / latest [what ever] to / comments / {commentId} [what ever]
  – / products / 1 / comments / 5 [还有什么]还有/ comments / {commentId} [什么都有]

和/ comments / {commentId}将是唯一的实现.

但是,我们在春季文档中找不到任何合适的内容……

解决方法:

您可以在控制器的@RequestMapping中添加其他URL路径前缀.

@RequestMapping(value = { "/products/{productId}", "/" })

这意味着您可以删除CommentsResource控制器,并且您将能够访问相同的资源：

/products/1/comments/5

并在

/comments/5

例如,这里：

 @GetMapping(value = "/comments/{commentNr}")
    public ResponseEntity<?> getComment(@PathVariable Long productId, @PathVaraible Long commentNr){
       // get comment with number commentNr of product productId
    }

显而易见的问题是productId路径变量.如果您使用的是Java 8,那么使用Optional可以很容易地解决这个问题：

@GetMapping(value = "/comments/{commentNr}")
public ResponseEntity<?> getComment(@PathVariable Optional<Long> productId, @PathVaraible Long commentNr){
    // get comment with number commentNr of product productId
    // Check whether productId exists
}

标签：java,spring,rest,spring-mvc,api-design
来源： https://codeday.me/bug/20190828/1755049.html