how to groupBy flatboject array in dataweave

Question

i have below array json which is from reading text/csv file . for example

[{
"no" : "2001",
"sendingStoreCode": "006091",
"receivingStoreCode": "006095",
"sku": "dddd",
"quantity": 1
},
{
"no" : "2001",
"sendingStoreCode": "006091",
"receivingStoreCode": "006095",
"sku": "xxxx",
"quantity": 1
},
{
"no" : "2002",
"sendingStoreCode": "006091",
"receivingStoreCode": "006095",
"sku": "xxxx",
"quantity": 1
}
]

now we have to groupBy #no, sendingStoreCode etc to merge data line, below is expected result ,may i know how to get it

[{
    "no": "2001",
    "sendingStoreCode": "006091",
    "receivingStoreCode": "006095",
    "deliveryItems": [{
            "line": 1,
            "sku": "dddd",
            "quantity": 1
        },
        {
            "line": 2,
            "sku": "xxxx",
            "quantity": 1
        }
    ]
}, {
    "no": "2002",
    "sendingStoreCode": "006091",
    "receivingStoreCode": "006095",
    "deliveryItems": [{
        "sku": "xxxx",
        "quantity": 1
    }]
}]

Answer 1

Maybe you can try something like this, notice that in the groupBy function, you have to create a single value that works as an id

%dw 2.0
output application/json
---
payload 
  groupBy ((item, index) -> item.no ++ "-" ++ item.sendingStoreCode ++ "-" ++ item.receivingStoreCode)
  pluck ((value, key, index) -> {
      no: value.no[0],
      sendingStoreCode: value.sendingStoreCode[0],
      receivingStoreCode: value.receivingStoreCode[0],
      deliveryItems: value map ((item, index) -> {
        "line" : index + 1,
        "sku": item.sku,
        "quantity": item.quantity
      })
  })