```ruby
require 'sinatra'
require 'omniauth'
require 'omniauth-oauth2'
require 'rack/ssl'
require 'pp'

# These variables should all be set in your environment
CLIENT_ID = ENV['CLIENT_ID']
CLIENT_SECRET = ENV['CLIENT_SECRET']
REDIRECT_URL = ENV['REDIRECT_URL']
AUTHORIZE_URL = ENV['AUTHORIZE_URL']
TOKEN_URL = ENV['TOKEN_URL']
SCOPE = ENV['SCOPE']

use Rack::SSL
use Rack::Session::Cookie
use OmniAuth::Builder do
  provider :oauth2, CLIENT_ID, CLIENT_SECRET, :client_options => {
             :authorize_url => AUTHORIZE_URL,
             :token_url => TOKEN_URL,
             :scope => SCOPE }
end

get '/auth/:name/callback' do
  pp request.env['omniauth.auth']
end

get '/*' do
  "Hello World!"
end
```

Use json for debugging for now
user
```ruby
require 'sinatra'
require 'omniauth'
require 'omniauth-oauth2'
require 'rack/ssl'
require 'json'

# These variables should all be set in your environment
CLIENT_ID = ENV['CLIENT_ID']
CLIENT_SECRET = ENV['CLIENT_SECRET']
REDIRECT_URL = ENV['REDIRECT_URL']
AUTHORIZE_URL = ENV['AUTHORIZE_URL']
TOKEN_URL = ENV['TOKEN_URL']
SCOPE = ENV['SCOPE']

use Rack::SSL
use Rack::Session::Cookie
use OmniAuth::Builder do
  provider :oauth2, CLIENT_ID, CLIENT_SECRET, :client_options => {
             :authorize_url => AUTHORIZE_URL,
             :token_url => TOKEN_URL,
             :scope => SCOPE }
end

get '/auth/:name/callback' do
  headers 'Content-Type' => 'application/json'
  request.env['omniauth.auth'].to_json
end

get '/*' do
  "Hello World!"
end
```
assistant