archive/phabricator
1
0
Fork 0
Code Issues 1 Pull Requests Packages Projects Releases Wiki Activity

Replace getPagingValue() with cursor methods

Browse Source 
Summary:
Ref T7803. Prior to this change sequence, Query classes conflated paging values (the actual thing that goes in a "x > 3" clause) with cursor values (arbitrary identifiers which track where the user is in a result list).

Although the two can sometimes be the same, the vast majority of implementations are simpler and better when object IDs are used as cursors and paging values are derived from them.

The new stuff handles this in a consistent way, so we're free to separate getPagingValue() from paging. The new method is essentially getResultCursor().

This also implements getPageCursors(), which allows queries to return directional cursors. The inability to do this was a practical limitation blocking the implementation of T7803.

Test Plan:
  - Browsed a bunch of results and paged through queries.
  - Grepped for removed methods.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T7803

Differential Revision: https://secure.phabricator.com/D12383
This commit is contained in:
epriestley
2015-04-12 16:44:15 -07:00
parent 09ad69238e
commit 8efdc4aabf
6 changed files with 41 additions and 34 deletions
Download Patch File Download Diff File Expand all files Collapse all files

46
src/infrastructure/query/policy/PhabricatorCursorPagedPolicyAwareQuery.php
View File

@@ -19,23 +19,35 @@ abstract class PhabricatorCursorPagedPolicyAwareQuery
private $orderVector;
private $builtinOrder;
protected function getPagingValue($result) {
if (!is_object($result)) {
// This interface can't be typehinted and PHP gets really angry if we
// call a method on a non-object, so add an explicit check here.
throw new Exception(pht('Expected object, got "%s"!', gettype($result)));
protected function getPageCursors(array $page) {
return array(
$this->getResultCursor(head($page)),
$this->getResultCursor(last($page)),
);
}
protected function getResultCursor($object) {
if (!is_object($object)) {
throw new Exception(
pht(
'Expected object, got "%s".',
gettype($object)));
}
return $result->getID();
return $object->getID();
}
protected function nextPage(array $page) {
// See getPagingViewer() for a description of this flag.
$this->internalPaging = true;
if ($this->beforeID) {
$this->beforeID = $this->getPagingValue(last($page));
if ($this->beforeID !== null) {
$page = array_reverse($page, $preserve_keys = true);
list($before, $after) = $this->getPageCursors($page);
$this->beforeID = $before;
} else {
$this->afterID = $this->getPagingValue(last($page));
list($before, $after) = $this->getPageCursors($page);
$this->afterID = $after;
}
}
@@ -113,7 +125,9 @@ abstract class PhabricatorCursorPagedPolicyAwareQuery
}
final public function executeWithCursorPager(AphrontCursorPagerView $pager) {
$this->setLimit($pager->getPageSize() + 1);
$limit = $pager->getPageSize();
$this->setLimit($limit + 1);
if ($pager->getAfterID()) {
$this->setAfterID($pager->getAfterID());
@@ -122,17 +136,19 @@ abstract class PhabricatorCursorPagedPolicyAwareQuery
}
$results = $this->execute();
$count = count($results);
$sliced_results = $pager->sliceResults($results);
if ($sliced_results) {
if ($pager->getBeforeID() || (count($results) > $pager->getPageSize())) {
$pager->setNextPageID($this->getPagingValue(last($sliced_results)));
list($before, $after) = $this->getPageCursors($sliced_results);
if ($pager->getBeforeID() || ($count > $limit)) {
$pager->setNextPageID($after);
}
if ($pager->getAfterID() ||
($pager->getBeforeID() && (count($results) > $pager->getPageSize()))) {
$pager->setPrevPageID($this->getPagingValue(head($sliced_results)));
($pager->getBeforeID() && ($count > $limit))) {
$pager->setPrevPageID($before);
}
}