json - 如何使用变量使用 Groovy 从 JSON 响应中提取值？

Question

我正在尝试使用存储在名为“jsonFieldName”的变量中的值的位置从 JSON 响应中提取自行车品牌“Cannondale”

或者，我可以使用以下语法成功提取品牌值(value):

def brand = json.store.bicycle.brand

但是，我想将元素的位置保存在一个变量中。原因是，我希望能够在 Json 响应上迭代多个断言，作为我的自动化套件的一部分。

有人可以建议如何做到这一点吗？

下面是我目前已将位置存储在变量中的片段。但它不起作用并且总是将品牌返回为“Null”:(谢谢。

def response = ('''{
   "store": {
  "book": [
     {
        "title": "Sword of Honour",
        "category": "fiction",
        "author": "Evelyn Waugh",
        "@price": 12.99
     },
     {
        "title": "Moby Dick",
        "category": "fiction",
        "author": "Herman Melville",
        "isbn": "0-553-21311-3",
        "@price": 8.99
     },
     {
        "title": "Sayings of the Century",
        "category": "reference",
        "author": "Nigel Rees",
        "@price": 8.95
     },
     {
        "title": "The Lord of the Rings",
        "category": "fiction",
        "author": "J. R. R. Tolkien",
        "isbn": "0-395-19395-8",
        "@price": 22.99
     }
  ],
  "bicycle": {
     "brand": "Cannondale",
     "color": "red",
     "price": 19.95
  }
 }
}''').toString()

//store location of json property I want to extract in property called jsonFieldName
def jsonFieldName = "store.bicycle.brand"
def json = new JsonSlurper().parseText (response)
//perform extraction
brand = json."${jsonFieldName}"

Answer 1

new JsonSlurper().parseText(response) 返回 map ，因此，搜索 "store.bicycle.brand" 将在 json 变量中查找名为 store.bicycle.brand 的键，同时您希望首先查看 json['store']，然后查看索引 ['bicycle']，依此类推。

我使用了一个inject 策略来做你想做的事:

def response = '''{
   "store": {
  "bicycle": {
     "brand": "Cannondale",
     "color": "red",
     "price": 19.95
  }
 }
}'''

def jsonFieldName = "store.bicycle.brand"
def json = new groovy.json.JsonSlurper().parseText (response)

get = { field, json2 ->
    field.tokenize(".").inject(json2) { map, f -> map[f] }
}

brand = get jsonFieldName, json
assert brand == 'Cannondale'