scala ujson.read() returns ujson.Obj - json

Question

I am trying to read a json string using Li Haoyi's ujson. This is the string:
{
"dataflows": [
{
"name": "test",
"sources": [
{
"name": "person_inputs",
"path": "/data/input/events/person/*",
"format": "JSON"
}
],
"transformations": [
{
"name": "validation",
"type": "validate_fields",
"params": {
"input": "person_inputs",
"validations": [
{
"field": "office",
"validations": [
"notEmpty"
]
},
{
"field": "age",
"validations": [
"notNull"
]
}
]
}
},
{
"name": "ok_with_date",
"type": "add_fields",
"params": {
"input": "validation_ok",
"addFields": [
{
"name": "dt",
"function": "current_timestamp"
}
]
}
}
],
"sinks": [
{
"input": "ok_with_date",
"name": "raw-ok",
"paths": [
"/data/output/events/person"
],
"format": "JSON",
"saveMode": "OVERWRITE"
},
{
"input": "validation_ko",
"name": "raw-ko",
"paths": [
"/data/output/discards/person"
],
"format": "JSON",
"saveMode": "OVERWRITE"
}
]
}
]
}
And this is how I read it:
val j = os.read(os.pwd/RelPath("src/main/scala/metadata.json"))
val jsonData = ujson.read(j)
But, the return type is ujson.Obj, and not Arr(ArrayBuffer(Obj), as expected, such that when I try to get jsonData(0), what I get is json.Value$InvalidData: Expected ujson.Arr.
I am asking this question because I have tried to use the ujson object to create a upickle object, but I cannot, and I suspect it is because of this initial error.
Any ideas of why this happens? Any help would be greatly appreciated! Thanks in advance!!

Answer 1

The outer element of your JSON is not an array, it is an object with a single element dataflows whose value is an array. Try jsonData("dataflows")(0).