Support remote host cache directives on profile photo fetching

1 files changed, 85 insertions, 41 deletions

diff --git a/include/photo/photo_driver.php b/include/photo/photo_driver.php
index 284206161..52f761b65 100644
--- a/include/photo/photo_driver.php
+++ b/include/photo/photo_driver.php
@@ -190,25 +190,27 @@ function delete_thing_photo($url, $ob_hash) {
  * * \e string \b 5 => modification date
  */
 function import_xchan_photo($photo, $xchan, $thing = false, $force = false) {
+
 	$modified = '';
 	$o = null;
-
 	$flags = (($thing) ? PHOTO_THING : PHOTO_XCHAN);
 	$album = (($thing) ? 'Things' : 'Contact Photos');
 
 	logger('Updating channel photo from ' . $photo . ' for ' . $xchan, LOGGER_DEBUG);
 
-	if($thing) {
+	if($thing)
 		$hash = photo_new_resource();
-	} else {
-		$r = q("select resource_id, edited, mimetype from photo where xchan = '%s' and photo_usage = %d and imgscale = 4 limit 1", dbesc($xchan), intval(PHOTO_XCHAN));
+	else {
+		$r = q("SELECT resource_id, edited, mimetype, expires, description FROM photo WHERE xchan = '%s' AND photo_usage = %d AND imgscale = 4 LIMIT 1", dbesc($xchan), intval(PHOTO_XCHAN));
 		if($r) {
 			$hash = $r[0]['resource_id'];
 			$modified = $r[0]['edited'];
 			$type = $r[0]['mimetype'];
-		} else {
-			$hash = photo_new_resource();
+			$exp = strtotime($r[0]['expires']);
+			$etag = $r[0]['description'];
 		}
+		else
+			$hash = photo_new_resource();
 	}
 
 	$photo_failure = false;
@@ -216,37 +218,74 @@ function import_xchan_photo($photo, $xchan, $thing = false, $force = false) {
 
 	if($photo) {
 
-		if($force || $modified == '') {
+		if($force || empty($modified))
 			$result = z_fetch_url($photo, true);
-		} else {
-			$h = [
-					'headers' => [
-							'If-Modified-Since: ' . gmdate('D, d M Y H:i:s', strtotime($modified . 'Z')) . ' GMT'
-					]
-			];
-			$result = z_fetch_url($photo, true, 0, $h);
+		elseif($exp - 60 < time()) {
+			$h = [];
+			$h[] = "If-Modified-Since: " . gmdate("D, d M Y H:i:s", $exp) . " GMT";
+			if(! empty($etag))
+				$h[] = "If-None-Match: " . $etag;
+			$result = z_fetch_url($photo, true, 0, [ 'headers' => $h ]);
 		}
 
-		if($result['success']) {
-			$img_str = $result['body'];
-			$type = guess_image_type($photo, $result['header']);
-			$modified = gmdate('Y-m-d H:i:s', (preg_match('/last-modified: (.+) \S+/i', $result['header'], $o) ? strtotime($o[1] . 'Z') : time()));
-			if(is_null($type))
+		if(isset($result)) {
+			$hdrs = [];
+			$h = explode("\n", $result['header']);
+			foreach ($h as $l) {
+				list($t,$v) = array_map("trim", explode(":", trim($l), 2));
+				$hdrs[strtolower($t)] = $v;
+			}
+
+			if(array_key_exists('expires', $hdrs))
+				$expires = strtotime($hdrs['expires']);
+				if($expires - 60 < time())
+					$expires = time() + 60;
+			else {
+				$cc = '';
+				if(array_key_exists('cache-control', $hdrs))
+					$cc = $hdrs['cache-control'];
+				if(strpos($cc, 'no-cache'))
+					$expires = time() + 60;
+				else {
+					$ttl = (preg_match('/max-age=(\d+)/i', $cc, $o) ? intval($o[1]) : 86400);
+					$expires = time() + $ttl;
+				}
+			}
+
+			$modified = gmdate('Y-m-d H:i:s', (array_key_exists('last-modified', $hdrs) ? strtotime($hdrs['last-modified']) : time()));
+
+			if($result['success']) {
+				$img_str = $result['body'];
+				$type = guess_image_type($photo, $result['header']);
+				if(is_null($type))
+					$photo_failure = true;
+			}
+			else
 				$photo_failure = true;
-		} elseif($result['return_code'] == 304) {
+		}
+
+		if(! isset($result) || $result['return_code'] == 304) {
 			$photo = z_root() . '/photo/' . $hash . '-4';
 			$thumb = z_root() . '/photo/' . $hash . '-5';
 			$micro = z_root() . '/photo/' . $hash . '-6';
-		} else {
+			if(isset($result))
+				q("UPDATE photo SET expires = '%s' WHERE xchan = '%s' and photo_usage = %d and imgscale IN (4, 5, 6)",
+					dbescdate(gmdate('Y-m-d H:i:s', (isset($expires) ? $expires : time() + 86400))),
+					dbesc($xchan),
+					intval(PHOTO_XCHAN)
+				);
+			$photo_notmodified = true;
 			$photo_failure = true;
 		}
-	} else {
-		$photo_failure = true;
 	}
+	else
+		$photo_failure = true;
+
+	if(! $photo_failure) {
 
-	if(!$photo_failure && $result['return_code'] != 304) {
 		$img = photo_factory($img_str, $type);
 		if($img->is_valid()) {
+
 			$width = $img->getWidth();
 			$height = $img->getHeight();
 
@@ -255,25 +294,28 @@ function import_xchan_photo($photo, $xchan, $thing = false, $force = false) {
 					// crop out the sides
 					$margin = $width - $height;
 					$img->cropImage(300, ($margin / 2), 0, $height, $height);
-				} elseif(($height / $width) > 1.2) {
+				}
+				elseif(($height / $width) > 1.2) {
 					// crop out the bottom
 					$margin = $height - $width;
 					$img->cropImage(300, 0, 0, $width, $width);
-				} else {
-					$img->scaleImageSquare(300);
 				}
-			} else {
-				$photo_failure = true;
+				else
+					$img->scaleImageSquare(300);
 			}
+			else
+				$photo_failure = true;
 
 			$p = [
-					'xchan' => $xchan,
-					'resource_id' => $hash,
-					'filename' => basename($photo),
-					'album' => $album,
-					'photo_usage' => $flags,
-					'imgscale' => 4,
-					'edited' => $modified,
+				'xchan' => $xchan,
+				'resource_id' => $hash,
+				'filename' => basename($photo),
+				'album' => $album,
+				'photo_usage' => $flags,
+				'imgscale' => 4,
+				'edited' => $modified,
+				'description' => (array_key_exists('etag', $hdrs) ? $hdrs['etag'] : ''),
+				'expires' => gmdate('Y-m-d H:i:s', (isset($expires) ? $expires : time() + 86400))
 			];
 
 			$r = $img->save($p);
@@ -295,12 +337,14 @@ function import_xchan_photo($photo, $xchan, $thing = false, $force = false) {
 			$photo = z_root() . '/photo/' . $hash . '-4';
 			$thumb = z_root() . '/photo/' . $hash . '-5';
 			$micro = z_root() . '/photo/' . $hash . '-6';
-		} else {
+		}
+		else {
 			logger('Invalid image from ' . $photo);
 			$photo_failure = true;
 		}
 	}
-	if($photo_failure) {
+
+	if($photo_failure && ! isset($photo_notmodified)) {
 		$default = get_default_profile_photo();
 		$photo = z_root() . '/' . $default;
 		$thumb = z_root() . '/' . get_default_profile_photo(80);
@@ -309,12 +353,12 @@ function import_xchan_photo($photo, $xchan, $thing = false, $force = false) {
 		$modified = gmdate('Y-m-d H:i:s', filemtime($default));
 	}
 
-	logger('HTTP code: ' . $result['return_code'] . '; modified: ' . $modified
-			. '; failure: ' . ($photo_failure ? 'yes' : 'no') . '; URL: ' . $photo, LOGGER_DEBUG);
+	logger('xchan: ' . $xchan . '; HTTP code: ' . (isset($result) && array_key_exists('return_code', $result) ? $result['return_code'] : 'none') . '; modified: ' . $modified . '; URL: ' . $photo, LOGGER_DEBUG);
 
-	return([$photo, $thumb, $micro, $type, $photo_failure, $modified]);
+	return([ $photo, $thumb, $micro, $type, $photo_failure, $modified ]);
 }
 
+
 /**
   * @brief Import channel photo from a URL.
  *