feat(vertex): add support for US multi-region endpoint

* feat: vertex us region

* fix lints

Author: mikecluck

src/Vertex/Client.php

@@ -55,7 +55,11 @@ private function __construct(
         );
 
         // @see https://docs.cloud.google.com/vertex-ai/docs/reference/rest#rest_endpoints
-        $baseUrl = 'https://'.$location.'-aiplatform.googleapis.com';
+        $baseUrl = match ($location) {
+            'global' => 'https://aiplatform.googleapis.com',
+            'us' => 'https://aiplatform.us.rep.googleapis.com',
+            default => 'https://'.$location.'-aiplatform.googleapis.com',
+        };
 
         parent::__construct(
             headers: [],

tests/Vertex/ClientTest.php

@@ -0,0 +1,61 @@
+<?php
+
+namespace Tests\Vertex;
+
+use Anthropic\Vertex\Client;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+class ClientTest extends TestCase
+{
+    /**
+     * @dataProvider locationBaseUrlProvider
+     */
+    public function testBaseUrlForLocation(string $location, string $expectedHost): void
+    {
+        $client = $this->createClientWithLocation($location);
+
+        $reflection = new \ReflectionMethod($client, 'getBaseUrl');
+        $baseUrl = $reflection->invoke($client);
+
+        $this->assertInstanceOf(\Psr\Http\Message\UriInterface::class, $baseUrl);
+        $this->assertSame($expectedHost, (string) $baseUrl);
+    }
+
+    /**
+     * @return iterable<string, array{string, string}>
+     */
+    public static function locationBaseUrlProvider(): iterable
+    {
+        yield 'global region' => ['global', 'https://aiplatform.googleapis.com'];
+
+        yield 'us region' => ['us', 'https://aiplatform.us.rep.googleapis.com'];
+
+        yield 'us-central1 region' => ['us-central1', 'https://us-central1-aiplatform.googleapis.com'];
+
+        yield 'europe-west1 region' => ['europe-west1', 'https://europe-west1-aiplatform.googleapis.com'];
+
+        yield 'asia-southeast1 region' => ['asia-southeast1', 'https://asia-southeast1-aiplatform.googleapis.com'];
+    }
+
+    private function createClientWithLocation(string $location): Client
+    {
+        $reflection = new \ReflectionClass(Client::class);
+        $constructor = $reflection->getConstructor();
+        assert(null !== $constructor);
+
+        $client = $reflection->newInstanceWithoutConstructor();
+
+        $credentialsProvider = function () {
+            throw new \RuntimeException('Should not be called in tests');
+        };
+
+        $constructor->invoke($client, $credentialsProvider, $location, 'test-project');
+
+        return $client;
+    }
+}