從 spring-boot 返回 JSON 響應作為 CSV 文件 controller

Question

在我的 spring-boot 項目中，我以 JSON 格式從外部 API 獲取信息。 響應表示如下：

{
  "id":237,
  "first_name":"LeBron",
  "last_name":"James",
  "position":"F",
  "height_feet": 6,
  "height_inches": 8,
  "weight_pounds": 250,
  "team":{
      "id":14,
      "abbreviation":"LAL",
      "city":"Los Angeles",
      "conference":"West",
      "division":"Pacific",
      "full_name":"Los Angeles Lakers",
      "name":"Lakers"
  }
}

我的任務是從這個 JSON 響應中返回一個 CSV 文件。 我在 inte.net 上尋找一些信息，只能找到從常規 JSON 到 CSV 的轉換，但我得到的 JSON 響應是嵌套的，轉換不起作用。 我怎樣才能讓它發生？ 我應該怎么辦？ 任何幫助將不勝感激。

Answer 1

一種方法是預處理 JSON 數據並將其轉換為平面 JSON 結構。 您可以編寫自己的方法來執行此操作，也可以使用 JOLT 庫來執行此操作：

樣本規格

[
  {
    "operation": "shift",
    "spec": {
      "*": "&",
      "team": {
        "id": "team-id",
        "abbreviation": "team-abbreviation",
        "city": "team-city",
        "conference": "team-conference",
        "division": "team-division",
        "full_name": "team-full-name",
        "name": "team-name"
      }
    }
  }
]

將 JSON 轉換為

{
  "id" : 237,
  "first_name" : "LeBron",
  "last_name" : "James",
  "position" : "F",
  "height_feet" : 6,
  "weight_pounds" : 250,
  "team-id" : 14,
  "team-abbreviation" : "LAL",
  "team-city" : "Los Angeles",
  "team-conference" : "West",
  "team-division" : "Pacific",
  "team-full-name" : "Los Angeles Lakers",
  "team-name" : "Lakers"
}

您可以在此處閱讀有關 JOLT 的更多信息 - https://github.com/bazaarvoice/jolt#Demo

您還可以在他們在 http 創建的演示頁面上實時測試您的規范： http://jolt-demo.appspot.com/#inception

編輯：在閱讀了更多文檔之后——這里是規范的一個較短版本，它將實現與上面給出的結果類似的結果：

[
  {
    "operation": "shift",
    "spec": {
      "*": "&",
      "team": {
        "*": "team-&"
      }
    }
  }
]

Answer 2

您可以使用庫Josson來完成這項工作。

https://github.com/octomix/josson

你的例子是 JSON object

Josson object = Josson.fromJsonString(
    "{" +
    "  \"id\":237," +
    "  \"first_name\":\"LeBron\"," +
    "  \"last_name\":\"James\"," +
    "  \"position\":\"F\"," +
    "  \"height_feet\": 6," +
    "  \"height_inches\": 8," +
    "  \"weight_pounds\": 250," +
    "  \"team\":{" +
    "      \"id\":14," +
    "      \"abbreviation\":\"LAL\"," +
    "      \"city\":\"Los Angeles\"," +
    "      \"conference\":\"West\"," +
    "      \"division\":\"Pacific\"," +
    "      \"full_name\":\"Los Angeles Lakers\"," +
    "      \"name\":\"Lakers\"" +
    "  }" +
    "}");

轉型

String keys = object.getString("flatten('.','[%d]').keys().csv()");
System.out.println(keys);
String values = object.getString("flatten('.','[%d]').csv()");
System.out.println(values);

Output

id,first_name,last_name,position,height_feet,height_inches,weight_pounds,team.id,team.abbreviation,team.city,team.conference,team.division,team.full_name,team.name
237,LeBron,James,F,6,8,250,14,LAL,Los Angeles,West,Pacific,Los Angeles Lakers,Lakers

如果輸入是一個 JSON 數組

Josson array = Josson.fromJsonString(
    "[{" +
    "  \"id\":237," +
    "  \"first_name\":\"LeBron\"," +
    "  \"last_name\":\"James\"," +
    "  \"position\":\"F\"," +
    "  \"height_feet\": 6," +
    "  \"height_inches\": 8," +
    "  \"weight_pounds\": 250," +
    "  \"team\":{" +
    "      \"id\":14," +
    "      \"abbreviation\":\"LAL\"," +
    "      \"city\":\"Los Angeles\"," +
    "      \"conference\":\"West\"," +
    "      \"division\":\"Pacific\"," +
    "      \"full_name\":\"Los Angeles Lakers\"," +
    "      \"name\":\"Lakers\"" +
    "  }" +
    "}," +
    "{" +
    "  \"id\":888," +
    "  \"first_name\":\"Anthony\"," +
    "  \"last_name\":\"Davis\"," +
    "  \"position\":\"F\"," +
    "  \"height_feet\": 6," +
    "  \"height_inches\": 10," +
    "  \"weight_pounds\": 253," +
    "  \"team\":{" +
    "      \"id\":14," +
    "      \"abbreviation\":\"LAL\"," +
    "      \"city\":\"Los Angeles\"," +
    "      \"conference\":\"West\"," +
    "      \"division\":\"Pacific\"," +
    "      \"full_name\":\"Los Angeles Lakers\"," +
    "      \"name\":\"Lakers\"" +
    "  }" +
    "}]");

轉型

String keys = array.getString("[0].flatten('.','[%d]').keys().csv()");
System.out.println(keys);
String values = array.getString("[]@.flatten('.','[%d]').csv().@join('\n')");
System.out.println(values);

Output

id,first_name,last_name,position,height_feet,height_inches,weight_pounds,team.id,team.abbreviation,team.city,team.conference,team.division,team.full_name,team.name
237,LeBron,James,F,6,8,250,14,LAL,Los Angeles,West,Pacific,Los Angeles Lakers,Lakers
888,Anthony,Davis,F,6,10,253,14,LAL,Los Angeles,West,Pacific,Los Angeles Lakers,Lakers