Homec4science
Diffusion Phabricator (stable) Browse

phab/src/applications/feed/publisher/PhabricatorFeedStoryPublisher.php
5623abecbf83stable

Last Change
Raw File

PhabricatorFeedStoryPublisher.php
View Options

<?php
/*
* Copyright 2011 Facebook, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
final class PhabricatorFeedStoryPublisher {
private $relatedPHIDs;
private $storyType;
private $storyData;
private $storyTime;
private $storyAuthorPHID;
public function setRelatedPHIDs(array $phids) {
$this->relatedPHIDs = $phids;
return $this;
}
public function setStoryType($story_type) {
$this->storyType = $story_type;
return $this;
}
public function setStoryData(array $data) {
$this->storyData = $data;
return $this;
}
public function setStoryTime($time) {
$this->storyTime = $time;
return $this;
}
public function setStoryAuthorPHID($phid) {
$this->storyAuthorPHID = $phid;
return $this;
}
public function publish() {
if (!$this->relatedPHIDs) {
throw new Exception("There are no PHIDs related to this story!");
}
if (!$this->storyType) {
throw new Exception("Call setStoryType() before publishing!");
}
$chrono_key = $this->generateChronologicalKey();
$story = new PhabricatorFeedStoryData();
$story->setStoryType($this->storyType);
$story->setStoryData($this->storyData);
$story->setAuthorPHID($this->storyAuthorPHID);
$story->setChronologicalKey($chrono_key);
$story->save();
$ref = new PhabricatorFeedStoryReference();
$sql = array();
$conn = $ref->establishConnection('w');
foreach (array_unique($this->relatedPHIDs) as $phid) {
$sql[] = qsprintf(
$conn,
'(%s, %s)',
$phid,
$chrono_key);
}
queryfx(
$conn,
'INSERT INTO %T (objectPHID, chronologicalKey) VALUES %Q',
$ref->getTableName(),
implode(', ', $sql));
return $story;
}
/**
* We generate a unique chronological key for each story type because we want
* to be able to page through the stream with a cursor (i.e., select stories
* after ID = X) so we can efficiently perform filtering after selecting data,
* and multiple stories with the same ID make this cumbersome without putting
* a bunch of logic in the client. We could use the primary key, but that
* would prevent publishing stories which happened in the past. Since it's
* potentially useful to do that (e.g., if you're importing another data
* source) build a unique key for each story which has chronological ordering.
*
* @return string A unique, time-ordered key which identifies the story.
*/
private function generateChronologicalKey() {
// Use the epoch timestamp for the upper 32 bits of the key. Default to
// the current time if the story doesn't have an explicit timestamp.
$time = nonempty($this->storyTime, time());
// Generate a random number for the lower 32 bits of the key.
$rand = head(unpack('L', Filesystem::readRandomBytes(4)));
// On 32-bit machines, we have to get creative.
if (PHP_INT_SIZE < 8) {
// We're on a 32-bit machine.
if (function_exists('bcadd')) {
// Try to use the 'bc' extension.
return bcadd(bcmul($time, bcpow(2, 32)), $rand);
} else {
// Do the math in MySQL. TODO: If we formalize a bc dependency, get
// rid of this.
$conn_r = id(new PhabricatorFeedStoryData())->establishConnection('r');
$result = queryfx_one(
$conn_r,
'SELECT (%d << 32) + %d as N',
$time,
$rand);
return $result['N'];
}
} else {
// This is a 64 bit machine, so we can just do the math.
return ($time << 32) + $rand;
}
}
}
c4science · Help