[WIP] Fix update detection for Dropbox

apps/files_external/lib/dropbox.php

@@ -63,17 +63,26 @@ private function deleteMetaData($path) {
  * @brief Returns the path's metadata
  * @param $path path for which to return the metadata
  * @param $list if true, also return the directory's contents
+ * @param $hash previously known hash, used to detect changes
  * @return directory contents if $list is true, file metadata if $list is
- * false, null if the file doesn't exist or "false" if the operation failed
+ * false, null if the file doesn't exist, "false" if the operation failed.
+ * If a hash is passed, "true" might be returned if the metadata didn't change
  */
- private function getMetaData($path, $list = false) {
+ private function getMetaData($path, $list = false, $hash = null) {
  $path = $this->root.$path;
- if ( ! $list && isset($this->metaData[$path])) {
+ if ( ! $list && ! $hash && isset($this->metaData[$path])) {
  return $this->metaData[$path];
  } else {
  if ($list) {
  try {
- $response = $this->dropbox->getMetaData($path);
+ $response = $this->dropbox->getMetaData($path, 'true');
+ // FIXME: why does Dropbox rerturn 401 unauthorized when passing a hash !?
+ //$response = $this->dropbox->getMetaData($path, 'true', $hash);
+ // FIXME: HACK, checking the hash here
+ if ($hash && $hash === $response['hash']) {
+ // no changes
+ return true;
+ }
  } catch (\Exception $exception) {
  \OCP\Util::writeLog('files_external', $exception->getMessage(), \OCP\Util::ERROR);
  return false;
@@ -96,7 +105,7 @@ private function getMetaData($path, $list = false) {
  return $contents;
  } else {
  try {
- $response = $this->dropbox->getMetaData($path, 'false');
+ $response = $this->dropbox->getMetaData($path, 'false', $hash);
  if (!isset($response['is_deleted']) || !$response['is_deleted']) {
  $this->metaData[$path] = $response;
  return $response;
@@ -308,4 +317,48 @@ public function touch($path, $mtime = null) {
  return true;
  }
 
+ public function hasUpdated($path, $time) {
+ // Dropbox doesn't have directory mtime, so need to use the Dropbox hash
+ // we stored as etag
+ $data = $this->getCache()->get($path);
+ // FIXME: might break if someone replaced a dir with a file with
+ // the same name before we got the update
+ if ($data['mimetype'] === 'httpd/unix-directory') {
+ $hash = $data['etag'];
+ $newData = $this->getMetaData($path, true, $hash);
+ return $newData !== true;
+ }
+ // use mtime for files
+ return parent::hasUpdated($path, $time);
+ }
+
+ public function getETag($path) {
+ // then retrieve the cached entry
+ $data = $this->getCache()->get($path);
+ // FIXME: might break if someone replaced a dir with a file with
+ // the same name before we got the update
+ if ($data && $data['mimetype'] === 'httpd/unix-directory' && isset($data['etag'])) {
+ // only check for changes
+ $metaData = $this->getMetaData($path, true, $data['etag']);
+ // no changes ?
+ if ($metaData === true) {
+ // return old etag
+ return $data['etag'];
+ }
+ }
+ else {
+ // FIXME: ouch, we need to get the directory contents to
+ // get the hash value, maybe there is a more efficient way to do this ?
+ $metaData = $this->getMetaData($path, true);
+ }
+
+ // this will get the cached entry for the directory
+ $metaData = $this->getMetaData($path);
+ if ($metaData && isset($metaData['is_dir']) && $metaData['is_dir'] && isset($metaData['hash'])) {
+ // for directories
+ return $metaData['hash'];
+ }
+ // files need to use the regular etag algo (no hash)
+ return parent::getEtag($path);
+ }
 }