Arvo的Scheme规范

谁借莪１个温暖的怀抱￠ 2022-05-16 00:56 213阅读 0赞

# **Arvo的Scheme规范** #

### **语法格式** ###

*  JSON格式

### **支持的【简单】类型** ###

1.  null------------no value
2.  boolean---------a binary value
3.  int ------------32 bit signed integer
4.  long------------64 bit signed integer
5.  float-----------single precision (32 bit)
6.  double----------double precision (64 bit)
7.  bytes-----------sequence of 8-bit unsigned bytes
8.  string----------unicode character sequence

### **支持的【复杂】类型** ###

1.  records
2.  enums
3.  arrays
4.  maps
5.  unions
6.  fixed

### **例子** ###

*  备注
    
    1.  name---名称
    2.  namespace---路径名称
    3.  doc---文档注释
    4.  aliases---别名
    5.  fileds---包含项
    6.  type---类型
    7.  default---默认值
    8.  symbols---枚举常量

<table style="margin-left:0px;"> 
 <thead style="margin-left:0px;"> 
 <tr style="margin-left:0px;"> 
 <th style="margin-left:0px;">序号</th> 
 <th style="margin-left:0px;">复杂类型</th> 
 <th style="margin-left:0px;">要求</th> 
 <th style="margin-left:0px;">例子</th> 
 </tr> 
 </thead> 
 <tbody style="margin-left:0px;"> 
 <tr style="margin-left:0px;"> 
 <td style="margin-left:0px;">1</td> 
 <td style="margin-left:0px;">Records</td> 
 <td style="margin-left:0px;"> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"type":"record" &nbsp;&nbsp;&nbsp;&nbsp;参数要求: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1、name【必须】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2、namespace &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3、doc【可选】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4、aliases【可选】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;5、fields【必须】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1、name【必须】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2、doc【可选】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3、type【必须】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4、default【可选】</td> 
 <td style="margin-left:0px;">{ "type": "record", "name": "LongList", "aliases": ["LinkedLongs"], fields" : [ &nbsp;&nbsp;{"name": "value", "type": "long"}, &nbsp;&nbsp;{"name": "next", "type": ["null", "LongList"]} ] }</td> 
 </tr> 
 <tr style="margin-left:0px;"> 
 <td style="margin-left:0px;">2</td> 
 <td style="margin-left:0px;">Enums</td> 
 <td style="margin-left:0px;"> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"type":"enum" &nbsp;&nbsp;&nbsp;&nbsp;参数要求: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1、name【必须】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2、namespace &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3、doc【可选】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4、aliases【可选】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4、symbols【必须】</td> 
 <td style="margin-left:0px;">{ "type": "enum", "name":&nbsp; "Suit", "symbols" : ["SPADES", "HEARTS", "DIAMONDS", "CLUBS"] }</td> 
 </tr> 
 <tr style="margin-left:0px;"> 
 <td style="margin-left:0px;">3</td> 
 <td style="margin-left:0px;">Arrays</td> 
 <td style="margin-left:0px;"> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"type":"array" &nbsp;&nbsp;&nbsp;&nbsp;参数要求: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1、items【必须--写子项的类型】</td> 
 <td style="margin-left:0px;">{"type": "array", "items": "string"}</td> 
 </tr> 
 <tr style="margin-left:0px;"> 
 <td style="margin-left:0px;">4</td> 
 <td style="margin-left:0px;">Maps</td> 
 <td style="margin-left:0px;"> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"type":"map" &nbsp;&nbsp;&nbsp;&nbsp;参数要求: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1、values【必须--写子项的类型】</td> 
 <td style="margin-left:0px;">{"type": "map", "values": "long"}</td> 
 </tr> 
 <tr style="margin-left:0px;"> 
 <td style="margin-left:0px;">5</td> 
 <td style="margin-left:0px;">Unions</td> 
 <td style="margin-left:0px;">类型：JSON上数组【Unions不能包含多个相同类型的Schema，除非是命名的record类型、命名的fixed类型和命名的enum类型】</td> 
 <td style="margin-left:0px;">["null","string"]</td> 
 </tr> 
 <tr style="margin-left:0px;"> 
 <td style="margin-left:0px;">6</td> 
 <td style="margin-left:0px;">Fixed</td> 
 <td style="margin-left:0px;"> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"type":"fixed" &nbsp;&nbsp;&nbsp;&nbsp;参数要求: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1、name【必须】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2、namespace &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3、size【必须】 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4、aliases【可选】</td> 
 <td style="margin-left:0px;">{"type": "fixed", "size": 16, "name": "md5"}</td> 
 </tr> 
 </tbody> 
</table>

### **复杂用法** ###

*  可以参考【[http://avro.apache.org/docs/current/spec.html][http_avro.apache.org_docs_current_spec.html]】

[http_avro.apache.org_docs_current_spec.html]: http://avro.apache.org/docs/current/spec.html