migration – Using the Migrate Plus API to select elements in a JSON array

I am new to Drupal, I need to solve the following error in my migration import.

For example, nest:

       nid: [
             value: "110538"
uuid: [
             value: "a90278c4-8bac-4539-b0c7-a6f62ed11975"
vid: [
            value: "110595"

What kind of field selector is needed to get nest value?

I have the following migrations:

plugin: url
data_fetcher_plugin: http
data_parser_plugin: json
URL: https://example.com/rest/article
type: whole
item_selector: /
the fields:
name: nest
label: 'Nest'
selector: nest
name: title
label: 'Title & # 39;
selector: / title
source_base_path: https: //example.com/'
nest: nest
title: title
plugin: default_value
default_value: & # 39; article & # 39;
plugin: "entity: node"
dependencies_migration: null

when i try to run the migration import, the following error has occurred:

 [warning]    array_flip (): Can only reverse the values ​​STRING and INTEGER! EntityStorageBase.php: 264
 [warning] Illegal offset type ContentEntityStorageBase.php: 955
 [warning] Type of illegal offset in isset or empty EntityStorageBase.php: 250

In Connection.php, line 729:

Placeholders must have an end [] if they must be extended with an array of values. 

I need help to solve this error.