Move caching logic to response

This avoids having to do it at all the places we want cached responses.

We can't inject the ITimeFactor without breaking public API.
However we can perfectly overwrite the service (resulting in the same
testable effect).

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>

2 files changed, 26 insertions, 4 deletions

diff --git a/lib/public/AppFramework/Http/Response.php b/lib/public/AppFramework/Http/Response.php
index 512b312dae1..a6f5afd3c18 100644
--- a/lib/public/AppFramework/Http/Response.php
+++ b/lib/public/AppFramework/Http/Response.php
@@ -35,6 +35,7 @@
 namespace OCP\AppFramework\Http;
 
 use OCP\AppFramework\Http;
+use OCP\AppFramework\Utility\ITimeFactory;
 
 /**
  * Base class for responses. Also used to just send headers.
@@ -95,12 +96,23 @@ class Response {
 	 * @return $this
 	 * @since 6.0.0 - return value was added in 7.0.0
 	 */
-	public function cacheFor($cacheSeconds) {
-
+	public function cacheFor(int $cacheSeconds) {
 		if($cacheSeconds > 0) {
 			$this->addHeader('Cache-Control', 'max-age=' . $cacheSeconds . ', must-revalidate');
+
+			// Old scool prama caching
+			$this->addHeader('Pragma', 'public');
+
+			// Set expires header
+			$expires = new \DateTime();
+			/** @var ITimeFactory $time */
+			$time = \OC::$server->query(ITimeFactory::class);
+			$expires->setTimestamp($time->getTime());
+			$expires->add(new \DateInterval('PT'.$cacheSeconds.'S'));
+			$this->addHeader('Expires', $expires->format(\DateTime::RFC2822));
 		} else {
 			$this->addHeader('Cache-Control', 'no-cache, no-store, must-revalidate');
+			unset($this->headers['Expires'], $this->headers['Pragma']);
 		}
 
 		return $this;
diff --git a/tests/lib/AppFramework/Http/ResponseTest.php b/tests/lib/AppFramework/Http/ResponseTest.php
index 9267d862600..5c867388369 100644
--- a/tests/lib/AppFramework/Http/ResponseTest.php
+++ b/tests/lib/AppFramework/Http/ResponseTest.php
@@ -27,6 +27,7 @@ namespace Test\AppFramework\Http;
 
 use OCP\AppFramework\Http\Response;
 use OCP\AppFramework\Http;
+use OCP\AppFramework\Utility\ITimeFactory;
 
 
 class ResponseTest extends \Test\TestCase {
@@ -222,15 +223,24 @@ class ResponseTest extends \Test\TestCase {
 
 		$headers = $this->childResponse->getHeaders();
 		$this->assertEquals('no-cache, no-store, must-revalidate', $headers['Cache-Control']);
+		$this->assertFalse(isset($headers['Pragma']));
+		$this->assertFalse(isset($headers['Expires']));
 	}
 
 
 	public function testCacheSeconds() {
+		$time = $this->createMock(ITimeFactory::class);
+		$time->method('getTime')
+			->willReturn('1234567');
+
+		$this->overwriteService(ITimeFactory::class, $time);
+
 		$this->childResponse->cacheFor(33);
 
 		$headers = $this->childResponse->getHeaders();
-		$this->assertEquals('max-age=33, must-revalidate',
-			$headers['Cache-Control']);
+		$this->assertEquals('max-age=33, must-revalidate', $headers['Cache-Control']);
+		$this->assertEquals('public', $headers['Pragma']);
+		$this->assertEquals('Thu, 15 Jan 1970 06:56:40 +0000', $headers['Expires']);
 	}