How to transfer data from one class to another class in Laravel?

Currently I am authorizing the Amadeus API and receiving an access token through a service class, i.e. Amadeus\Client . There are several API endpoints for multiple functions, so I want to maintain separate classes for separate endpoints. Each endpoint requires access token to process the request. How can I transfer the authorization token form the Amadeus\Client to Amadeus\FlightOffersSearch so I can pass the access token into the headers of the endpoint. Please can someone help me here?

Amadeus\Client

class Client
{
    public function __construct(
        protected string $uri,
        protected string $client_id,
        protected string $client_secret,
        protected string $grant_type,
    ) {}

    public function authorization() {

        $uri = $this->uri;
        $auth_data = array(
            'client_id' => $this->client_id,
            'client_secret' => $this->client_secret,
            'grant_type' =>  $this->grant_type
        );

        $requests_response = Http::asForm()->post($uri, $auth_data);
        $response_body = json_decode($requests_response->body());
        $access_token = $response_body->access_token;

        return $access_token;
}

Amadeus\FlightOffersSearch

class Flight
{
    public function get_flight() {

        if(isset($access_token)){
            $endpoint = 'https://test.api.amadeus.com/v2/shopping/flight-offers';
            $travel_data = array(
                'originLocationCode' => 'BOS',
                'destinationLocationCode' => 'PAR',
                'departureDate' => '2022-06-14',
                'adults' => 2
            );
            $params = http_build_query($travel_data);
            $url = $endpoint.'?'.$params;
            $headers = array('Authorization' => 'Bearer '.$access_token);
        }
    }
}

This is more PHP specific than Laravel. I suggest you make the client a singleton class where you encapsulate all the authentication logic and just get the client instance when you need it using a static method.

I also highly recommend using GuzzleHttp for HTTP client.

Something like this draft.

<?php

namespace App;

use GuzzleHttp\Client;

class AmadeusClient
{
    private static $instance;
    private $client;
    private $token;

    public function __construct()
    {
        throw_if(static::$instance, 'There should be only one instance of this class');
        static::$instance = $this;
        $this->client = new Client([
            'base_uri' => 'https://test.api.amadeus.com/v2/',
        ]);
    }

    private function authenticate()
    {
        if (!$this->token) {
            $client_id = env('api_client_id');
            $client_secret = env('api_client_secret');
            $grant_type = env('api_grant_type$a');

            $this->token = ''; // TODO: get authorization token using $this->client;
        }
    }

    public static function getInstance()
    {
        return static::$instance ?: (new static());
    }

    public function get($uri, array $options = [])
    {
        $this->authenticate();
        return $this->client->get($uri, $options);
    }

    public function post($uri, array $options = [])
    {
        $this->authenticate();
        return $this->client->post($uri, $options);
    }
}

You would then use it like this:

$client = AmadeusClient::getInstance();
$client->get('shopping/flight-offers', $options);