Ver.2 Token service class is implemented.

Author: msyk

composer.json

@@ -1,6 +1,6 @@
 {
   "name": "msyk/dropbox-api-shortlivedtoken",
-  "version": "1",
+  "version": "2",
   "time": "2022-07-07",
   "repositories": [
     {
@@ -42,5 +42,10 @@
     "clear": [
       "rm -rf node_modules vendor"
     ]
+  },
+  "autoload": {
+    "psr-4": {
+      "msyk\\DropboxAPIShortLivedToken\\": "src/"
+    }
   }
 }

index.php

@@ -4,6 +4,8 @@
 
 require_once __DIR__ . '/vendor/autoload.php';
 
+use msyk\DropboxAPIShortLivedToken\AutoRefreshingDropBoxTokenService;
+
 // Check the existence of the credentials.php file, and include it.
 $credFile = __DIR__ . '/credentials.php';
 if (!file_exists($credFile)) {
@@ -16,25 +18,9 @@
 use Spatie\Dropbox\Client;
 
 try {
-    // Get the access token from refresh token. Referred from https://www.softel.co.jp/blogs/tech/archives/7067
-    $data = http_build_query(['grant_type' => 'refresh_token', 'refresh_token' => $refreshToken,], '', '&');
-    $options = [
-        'http' => [
-            'ignore_errors' => true, 'method' => 'POST',
-            'header' => [
-                'Content-type: application/x-www-form-urlencoded',
-                'Authorization: Basic ' . base64_encode($appKey . ':' . $appSecret),
-            ],
-            'content' => $data,
-        ],
-    ];
-    $context = stream_context_create($options);
-    $response = json_decode(file_get_contents('https://api.dropbox.com/oauth2/token', false, $context));
-    $accessKey = $response->access_token;
-    ////////////////////////////////////////////////
-
+    $tokenProvider = new AutoRefreshingDropBoxTokenService($refreshToken, $appKey, $appSecret);
     // List the items on the root of your dropbox with spatie/dropbox-api
-    $client = new Client($accessKey);
+    $client = new Client($tokenProvider);
     $list = $client->listFolder("/");
 } catch (\Exception $ex) {
     var_export($ex->getMessage()); // Very simple output.

src/AutoRefreshingDropBoxTokenService.php

@@ -0,0 +1,38 @@
+<?php
+
+namespace msyk\DropboxAPIShortLivedToken;
+
+use Spatie\Dropbox\TokenProvider;
+
+class AutoRefreshingDropBoxTokenService implements TokenProvider
+{
+    private $refreshToken;
+    private $appKey;
+    private $appSecret;
+
+    public function __construct($refreshToken, $appKey, $appSecret)
+    {
+        $this->refreshToken = $refreshToken;
+        $this->appKey = $appKey;
+        $this->appSecret = $appSecret;
+    }
+
+    public function getToken(): string
+    {
+        // Get the access token from refresh token. Referred from https://www.softel.co.jp/blogs/tech/archives/7067
+        $data = http_build_query(['grant_type' => 'refresh_token', 'refresh_token' => $this->refreshToken,], '', '&');
+        $options = [
+            'http' => [
+                'ignore_errors' => true, 'method' => 'POST',
+                'header' => [
+                    'Content-type: application/x-www-form-urlencoded',
+                    'Authorization: Basic ' . base64_encode($this->appKey . ':' . $this->appSecret),
+                ],
+                'content' => $data,
+            ],
+        ];
+        $context = stream_context_create($options);
+        $response = json_decode(file_get_contents('https://api.dropbox.com/oauth2/token', false, $context));
+        return $response->access_token;
+    }
+}