Replace JWT Micropub tokens with revocable opaque tokens

Tokens now store a hashed row in micropub_tokens instead of being
self-contained signed JWTs, so a leaked or unwanted token can actually
be revoked. Since revocation already requires a DB lookup on every
request, JWT's stateless-verification benefit was gone anyway, so this
also drops the lcobucci/jwt dependency entirely.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014625MfkGZ7GVdbqKme4a8L

tests/Feature/TokenServiceTest.php

@@ -4,18 +4,16 @@ declare(strict_types=1);
 
 namespace Tests\Feature;
 
+use App\Models\MicropubToken;
 use App\Services\TokenService;
-use DateTimeImmutable;
-use Lcobucci\JWT\Configuration;
-use Lcobucci\JWT\Signer\Key\InMemory;
 use PHPUnit\Framework\Attributes\Test;
 use Tests\TestCase;
 
 class TokenServiceTest extends TestCase
 {
     /**
-     * Given the token is dependent on a random nonce, the time of creation and
-     * the APP_KEY, to test, we shall create a token, and then verify it.
+     * Given the token is dependent on a random value and stored only as a
+     * hash, to test, we shall create a token, and then verify it.
      */
     #[Test]
     public function tokenservice_creates_valid_tokens(): void
@@ -41,24 +39,29 @@ class TokenServiceTest extends TestCase
     }
 
     #[Test]
-    public function tokens_with_different_signing_key_are_not_valid(): void
+    public function unknown_tokens_are_not_valid(): void
     {
+        $response = $this->get('/api/post', ['HTTP_Authorization' => 'Bearer '.bin2hex(random_bytes(32))]);
+
+        $response->assertJson([
+            'response' => 'error',
+            'error' => 'invalid_token',
+            'error_description' => 'The provided token did not pass validation',
+        ]);
+    }
+
+    #[Test]
+    public function revoked_tokens_are_not_valid(): void
+    {
+        $tokenService = new TokenService;
         $data = [
             'me' => 'https://example.org',
             'client_id' => 'https://quill.p3k.io',
             'scope' => 'post',
         ];
+        $token = $tokenService->getNewToken($data);
 
-        $config = resolve(Configuration::class);
-
-        $token = $config->builder()
-            ->issuedAt(new DateTimeImmutable)
-            ->withClaim('client_id', $data['client_id'])
-            ->withClaim('me', $data['me'])
-            ->withClaim('scope', $data['scope'])
-            ->withClaim('nonce', bin2hex(random_bytes(8)))
-            ->getToken($config->signer(), InMemory::plainText(random_bytes(32)))
-            ->toString();
+        MicropubToken::where('token_hash', hash('sha256', $token))->firstOrFail()->revoke();
 
         $response = $this->get('/api/post', ['HTTP_Authorization' => 'Bearer '.$token]);