我正在编写一个 REST API，但我偶然发现了一个问题。返回验证错误的最佳方法是什么。

到目前为止，我一直在返回转储到一般错误代码中的错误消息(例如错误请求)

{
    "status": 400,
    "error": {
        "code": 1, // General bad request code
        "message": [
                "The Key \"a\" is missing",
                "The Key \"b\" is missing",
                "The Key \"c\" is missing",
                "Incorrect Format for field \"y\""
         ]
    }

)

我对良好的 API 响应应该是什么样子进行了更多研究，并想到了以下选项:

1. 在第一个遇到的错误处停止并返回带有特定错误代码的响应

   {
      "status": 400, //Same as the HTTP header returned
      "error" {
           "code": 1, // Specific field validation error code
           "message": "Field \"x\" is missing from the array structure",
           "developer_message": "The request structure must contain the following fields {a,b,c{x,y,z}}",
           "more_info" => "www.api.com/help/errors/1"
       }
   )
   

2. 解析所有请求数据，返回多个字段验证错误。

   {
     "status": 400,
     "error": {
       "code": 1 //General bad Request code
       "message": "Bad Request",
       "developer_message": "Field validation errors."
       "more_info": "www.api.com/help/errors/1",
       "error_details": {
               0: {
                       "code": 2 // Specific field validation error code
                       "message": "Field \"x\" is missing from the array structure",
                       "developer_message": "The request structure must contain the following fields {a,b,c{x,y,z}}",
                       "more_info": "www.api.com/help/errors/2"
                   },
   
               1: {
                       "code": 3 // Specific field validation error code
                       "message": "Incorrect Format for field \"y\"",
                       "developer_message": "The field \"y\" must be in the form of \"Y-m-d\"",
                       "more_info": "www.api.com/help/errors/3"
                  }
                      }
         }
     }
   

在我看来，选项 2 是正确的方式(它为开发人员/最终用户提供了更多有用的信息，并且服务器负载可能更低(更少的请求/无需重新验证有效数据/无需计算签名和对用户进行身份验证))，但我正在徘徊什么是最佳实践，以及是否有另一种方法来处理此类问题。

如果我在脚本流程中遇到一个 fatal error ，我认为选项 1 仍然有效。(不是验证错误)

请注意，代码只是一个简单的数组，以便于理解。响应格式为 JSON 或 XML。

最佳答案

让我们看看Facebook's Graph API .这受到了重创，并且很可能会产生很多错误。以下是 Facebook 在 API 错误时返回的内容:

 {
   "error": {
     "message": "Message describing the error", 
     "type": "OAuthException", 
     "code": 190,
     "error_subcode": 460,
     "error_user_title": "A title",
     "error_user_msg": "A message"
   }
 }

他们试图使 Graph API 尽可能有用，但他们似乎返回带有代码和子代码 (Ref) 的特定错误。每个错误都有自己的代码这一事实意味着更容易搜索所述代码或消息作为调试的起点。这可能就是他们不在官方错误响应中累积错误消息的原因。如果它对 Facebook 来说足够好和方便，那对我们来说可能就足够了。

错误响应示例:

{
  "error": {
    "message": "(#200) Must have a valid access_token to access this endpoint", 
    "type": "OAuthException", 
    "code": 200
  }
}

和

"error": {
  "message": "(#604) Your statement is not indexable. The WHERE clause must contain 
   an indexable column. Such columns are marked with * in the tables linked from
   http://developers.facebook.com/docs/reference/fql ", 
  "type": "OAuthException", 
  "code": 604
}

然后是JSend “这是一个规范，它为来自 Web 服务器的 JSON 响应的格式设置了一些规则。”他们的目标是:

There are lots of web services out there providing JSON data, and each has its own way of formatting responses. Also, developers writing for JavaScript front-ends continually re-invent the wheel on communicating data from their servers. While there are many common patterns for structuring this data, there is no consistency in things like naming or types of responses. Also, this helps promote happiness and unity between backend developers and frontend designers, as everyone can come to expect a common approach to interacting with one another.

这是一个示例错误消息:

{
    "status" : "fail",
    "data" : { "title" : "A title is required" }
}

看起来 Facebook 和这个试图树立行业标准的团队正在选择您的选择 #1。

赏金问题

为了响应“如果有人去了#2 并且可能有任何改进？”的赏金请求，有一个来自 Pragmatic RESTful API 的设计模式。说明:

Validation errors will need a field breakdown. This is best modeled by using a fixed top-level error code for validation failures and providing the detailed errors in an additional errors field, like so:

{
  "code" : 1024,
  "message" : "Validation Failed",
  "errors" : [
    {
      "code" : 5432,
      "field" : "first_name",
      "message" : "First name cannot have fancy characters"
    },
    {
       "code" : 5622,
       "field" : "password",
       "message" : "Password cannot be blank"
    }
  ]
}

关于json - REST API 错误代码返回结构，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/18470136/