Laravel Passport Password Grant token request. Uses config's "app.url" to make it environment agnostic.

getAccessToken.php

<? php
/*
|--------------------------------------------------------------------------------
| Environment Agnostinc: Requesting Password Grant Tokens Laravel using Passport
|--------------------------------------------------------------------------------
|
| Ref: https://laravel.com/docs/5.8/passport#requesting-password-grant-tokens
| Set the environment url in .env. Example: http://localhost for local dev server
| Use config('app.url') in the post request
| Makes makes it easy for testing APIs in tools like Postman
| Returns JSON
|
*/
$http = new GuzzleHttp\Client;

// Make sure "APP_URL" is properly set in the .env file
$oAuthUrl = config('app.url') . '/oauth/token';
try {
    $response = $http->post($oAuthUrl, [
        'form_params' => [
            'grant_type' => 'password',
            'client_id' => YOUR_PASSPORT_CLIENT_ID,
            'client_secret' => 'YOUR PASSPORT CLIENT SECRET',
            'username' => $request->username,
            'password' => $request->password,
            'scope' => '*',
        ],
    ]);
    return response()->json(['token' => json_decode((string) $response->getBody(), true)], 200);
} catch (\Exception $e) {
    return response()->json(['error'=>$e->getMessage()], $e->getCode());
}