Groovy从地图和子地图收集 [英] Groovy collect from map and submap

问题描述

我需要将JSON响应转换为csv文件.我可以从这里成功使用Tim Yates的出色代码: Groovy代码将json转换为CSV文件

I had a requirement to convert a JSON response into a csv file. I was able to successfully use Tim Yates' excellent code from here: Groovy code to convert json to CSV file

我现在还需要在csv中包括JSON的嵌套子图.地图和子地图之间的关系是1:1.

I now need to include the JSON's nested submap in the csv as well. The relationship between the map and submap is 1:1.

我一直无法为collect语句获得正确的语法，该语句将检索已解析的地图和子地图的键/值.

I've been unable to get the correct syntax for a collect statement that will retrieve both the parsed map and submap key/values.

示例JSON

{items=
[
{ 
  created_at=2019-03-27
, entity_id=1
, extension_attributes=[]
},

{
  created_at=2019-03-27
, entity_id=2
, extension_attributes= { employee_id=Emp1, employee_type=CSR}//nested submap
}
]}

时髦

import groovy.json.*

def data = new JsonSlurper().parseText( json ); //"json" is from GET request

def columns = ["created_at","entity_id","employee_id","employee_type"]

def encode = { e -> e ? /"$e"/ : "$e"}

requestFile.append( columns.collect { c -> encode( c ) }.join( ',' ) + '\n');

requestFile.append( data.items.collect { row ->columns.collect { colName -> encode( row[ colName ] ).replaceAll("null","") }.join( ',' )}.join( '\n' ) );//unsure how to use data.items.collect to fetch submap

我想 1)如下转换JSON，以轻松收集每个键/值:

I would like to either 1) Convert the JSON as follows to collect each key/value easily:

...
{
  created_at=2019-03-27
, entity_id=2
, employee_id=Emp1
, employee_type=CSR
}
...

或2)找出是否可以使用Groovy的collect方法将地图/子地图检索为平面地图.

or 2) Find out if there's a way to use Groovy's collect method to retrieve the map/submap as a flat map.

很不幸，我不是一名程序员，任何帮助将不胜感激！

I am unfortunately not a programmer by trade, and any help would be appreciated!

推荐答案

以下是flatten闭包，该闭包以递归方式展平了一个项目:

Here is the flatten closure which flattens an item recursively:

def flatten
flatten = { row ->
    def flattened = [:]
    row.each { k, v ->
        if (v instanceof Map) {
            flattened << flatten(v)
        } else {
            flattened[k] = v
        }
    }
    flattened
}

您应该在最后一行将row替换为flatten(row)，这样看起来就像这样:

You should just replace row with flatten(row) at your last line so it looks like this:

requestFile.append(data.items.collect { row ->
    columns.collect {
        colName -> encode(flatten(row)[colName]).replaceAll("null", "")
    }.join(',')
}.join('\n'))

结果如下:

"created_at","entity_id","employee_id","employee_type"

"2019-03-27","1",,
"2019-03-27","2","Emp1","CSR"

这篇关于Groovy从地图和子地图收集的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！