Convert json to hash to insert with Active Record - ruby-on-rails

Question

I'm still practising processing arrays and hashes, and particularly getting to details in 2d or 3d structures. I'm trying to use details in a json file to process some data ready to insert into the db with Active Record.
Here is my json structure for 'my_file.json'
# my_file.json
[
{
"name": "Joe Bloggs",
"telephone": "012-345-6789"
},
{
"name": "Hilda Bloggs",
"telephone": "012-345-6789"
}
]
and here is the code I'm using to convert the json data into something I can insert into my db
def json_insert_to_db
require 'json'
file = File.read('my_file.json')
json_data = JSON.parse(file)
details = json_data.map do |x|
user = User.new
user.name = json_data[x]['name']
user.telephone = json_data[x]['telephone']
end
end
With this I get
NameError: uninitialized constant User
(User does exist in the database, by the way)
I can't work out where I'm going wrong, but I know it's something simple I am overlooking. Thanks for any help.

Answer 1

The User model was set up but my db had a migration issue. However, beyond that, at the time I was still unable to build what I needed when importing the json file.
I have now worked out how to do it. The migration issue was resolved and I also revised the structure of my json file first, for clarity.
# my_file.json
{
"new_users":
[{
"name": "Joe Bloggs",
"telephone": "012-345-6789",
},
{
"name": "Hilda Bloggs",
"telephone": "012-345-6789",
}]
}
And my script...
require 'json'
file = File.read('my_file.json')
json_data = JSON.parse(file)['new_users']
#new_users = json_data.each do |key,value|
#new_user = User.new
#new_user.name = key['name']
#new_user.telephone = key['telephone']
end
#new_users.each { |x| puts x }