How to specify schema for nested json in flask_restx?

Solution

backup_fields = api.model('Backup fields', {
    "backup_status": fields.String,
    "backup_folder": fields.String
})

dr_status_fields = api.model('DR Status', {
    "elasticsearch": fields.Nested(backup_fields),
    "mongodb": fields.Nested(backup_fields),
    "postgresdb": fields.Nested(backup_fields),
    "overall_backup_status": fields.String
})