A Laravel integration for Xero using the Oauth 2.0 spec

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Http\Controllers\Controller;
use Webfox\Xero\OauthCredentialManager;

class XeroController extends Controller
{

    public function index(Request $request, OauthCredentialManager $xeroCredentials)
    {
        try {
            // Check if we've got any stored credentials
            if ($xeroCredentials->exists()) {
                /* 
                 * We have stored credentials so we can resolve the AccountingApi, 
                 * If we were sure we already had some stored credentials then we could just resolve this through the controller
                 * But since we use this route for the initial authentication we cannot be sure!
                 */
                $xero             = resolve(\XeroAPI\XeroPHP\Api\AccountingApi::class);
                $organisationName = $xero->getOrganisations($xeroCredentials->getTenantId())->getOrganisations()[0]->getName();
                $user             = $xeroCredentials->getUser();
                $username         = "{$user['given_name']} {$user['family_name']} ({$user['username']})";
            }
        } catch (\throwable $e) {
            // This can happen if the credentials have been revoked or there is an error with the organisation (e.g. it's expired)
            $error = $e->getMessage();
        }

        return view('xero', [
            'connected'        => $xeroCredentials->exists(),
            'error'            => $error ?? null,
            'organisationName' => $organisationName ?? null,
            'username'         => $username ?? null
        ]);
    }

}

/* 
 * We name this route xero.auth.success as by default the config looks for a route with this name to redirect back to
 * after authentication has succeeded. The name of this route can be changed in the config file.
 */
Route::get('/manage/xero', [\App\Http\Controllers\XeroController::class, 'index'])->name('xero.auth.success');

$this->app->bind(OauthCredentialManager::class, function(Application $app) {
    return new UserStorageProvider(
        \Auth::user(), // Storage Mechanism 
        $app->make('session.store'), // Used for storing/retrieving oauth 2 "state" for redirects
        $app->make(\Webfox\Xero\Oauth2Provider::class) // Used for getting redirect url and refreshing token
    );
});

<?php

namespace App\Http\Controllers;

use Webfox\Xero\Webhook;
use Illuminate\Http\Request;
use Illuminate\Http\Response;
use XeroApi\XeroPHP\Models\Accounting\Contact;
use XeroApi\XeroPHP\Models\Accounting\Invoice;

class XeroWebhookController extends Controller
{
    public function __invoke(Request $request, Webhook $webhook)
    {

        // The following lines are required for Xero's 'itent to receive' validation
        if (!$webhook->validate($request->header('x-xero-signature'))) {
            // We can't use abort here, since Xero expects no response body
            return response('', Response::HTTP_UNAUTHORIZED);
        }

        // A single webhook trigger can contain multiple events, so we must loop over them
        foreach ($webhook->getEvents() as $event) {
            if ($event->getEventType() === 'CREATE' && $event->getEventCategory() === 'INVOICE') {
                $this->invoiceCreated($request, $event->getResource());
            } elseif ($event->getEventType() === 'CREATE' && $event->getEventCategory() === 'CONTACT') {
                $this->contactCreated($request, $event->getResource());
            } elseif ($event->getEventType() === 'UPDATE' && $event->getEventCategory() === 'INVOICE') {
                $this->invoiceUpdated($request, $event->getResource());
            } elseif ($event->getEventType() === 'UPDATE' && $event->getEventCategory() === 'CONTACT') {
                $this->contactUpdated($request, $event->getResource());
            }
        }

        return response('', Response::HTTP_OK);
    }

    protected function invoiceCreated(Request $request, Invoice $invoice)
    {
    }

    protected function contactCreated(Request $request, Contact $contact)
    {
    }

    protected function invoiceUpdated(Request $request, Invoice $invoice)
    {
    }

    protected function contactUpdated(Request $request, Contact $contact)
    {
    }

}