Set packages.json last modified based on a provider-latest timestamp

src/Controller/ProxyController.php

@@ -41,7 +41,7 @@ public function __construct(ProxyRegister $register)
      */
     public function packages(Request $request): JsonResponse
     {
-        $providerHash = $this->register->getByHost('packagist.org')->latestProviderHash();
+        $metadata = $this->register->getByHost('packagist.org')->latestProvider();
         $response = (new JsonResponse([
             'notify-batch' => $this->generateUrl('package_downloads', [], RouterInterface::ABSOLUTE_URL),
             'providers-url' => '/p/%package%$%hash%.json',
@@ -54,12 +54,18 @@ public function packages(Request $request): JsonResponse
                 ],
             ],
             'providers-lazy-url' => '/p/%package%',
-            'provider-includes' => $providerHash !== null ? ['p/provider-latest$%hash%.json' => ['sha256' => $providerHash]] : [],
+            'provider-includes' => $metadata->isPresent() ? ['p/provider-latest$%hash%.json' => ['sha256' => $metadata->get()->hash()]] : [],
         ]))
             ->setPublic()
-            ->setTtl(360)
         ;
 
+        $now = new \DateTime();
+        $response->setLastModified(
+            $metadata->isPresent() ?
+            $now->setTimestamp($metadata->get()->timestamp()) :
+            $now
+        );
+
         $response->isNotModified($request);
 
         return $response;

src/Service/Proxy.php

@@ -81,17 +81,25 @@ public function providers(string $version, string $hash): Option
         return $this->fetchMetadata(sprintf('%s/provider/provider-%s$%s.json', $this->url, $version, $hash));
     }
 
-    public function latestProviderHash(): ?string
+    /**
+     * @return Option<Metadata>
+     */
+    public function latestProvider(): Option
     {
         foreach ($this->filesystem->listContents($this->name.'/provider') as $file) {
             if ($file['type'] === 'file' && $file['extension'] === 'json') {
                 preg_match('/\$(?<hash>.+)$/', $file['filename'], $matches);
 
-                return $matches['hash'];
+                if (($hash = $matches['hash']) !== null) {
+                    return $this->fetchMetadata(
+                        sprintf('%s/provider/provider-latest$%s.json', $this->url, $hash),
+                        $hash
+                    );
+                }
             }
         }
 
-        return null;
+        return Option::none();
     }
 
     /**
@@ -249,7 +257,7 @@ private function decodeMetadata(string $package): array
     /**
      * @return Option<Metadata>
      */
-    private function fetchMetadata(string $url): Option
+    private function fetchMetadata(string $url, ?string $hash = null): Option
     {
         $path = $this->metadataPath($url);
         if (!$this->filesystem->has($path)) {
@@ -263,7 +271,8 @@ private function fetchMetadata(string $url): Option
 
         return Option::some(new Metadata(
             (int) $this->filesystem->getTimestamp($path),
-            $stream
+            $stream,
+            $hash
         ));
     }
 

src/Service/Proxy/Metadata.php

@@ -15,13 +15,16 @@ final class Metadata
      */
     private $stream;
 
+    private ?string $hash = null;
+
     /**
      * @param resource $stream
      */
-    public function __construct(int $timestamp, $stream)
+    public function __construct(int $timestamp, $stream, ?string $hash = null)
     {
         $this->timestamp = $timestamp;
         $this->stream = $stream;
+        $this->hash = $hash;
     }
 
     public static function fromString(string $string): self
@@ -41,4 +44,9 @@ public function stream()
     {
         return $this->stream;
     }
+
+    public function hash(): ?string
+    {
+        return $this->hash;
+    }
 }