MyShaarli/application/History.php

201 lines
4.7 KiB
PHP
Raw Normal View History

<?php
/**
* Class History
*
* Handle the history file tracing events in Shaarli.
* The history is stored as JSON in a file set by 'resource.history' setting.
*
* Available data:
* - event: event key
* - datetime: event date, in ISO8601 format.
* - id: event item identifier (currently only link IDs).
*
* Available event keys:
* - CREATED: new link
* - UPDATED: link updated
* - DELETED: link deleted
* - SETTINGS: the settings have been updated through the UI.
*
* Note: new events are put at the beginning of the file and history array.
*/
class History
{
/**
* @var string Action key: a new link has been created.
*/
const CREATED = 'CREATED';
/**
* @var string Action key: a link has been updated.
*/
const UPDATED = 'UPDATED';
/**
* @var string Action key: a link has been deleted.
*/
const DELETED = 'DELETED';
/**
* @var string Action key: settings have been updated.
*/
const SETTINGS = 'SETTINGS';
/**
* @var string History file path.
*/
protected $historyFilePath;
/**
* @var array History data.
*/
protected $history;
/**
* @var int History retention time in seconds (1 month).
*/
protected $retentionTime = 2678400;
/**
* History constructor.
*
* @param string $historyFilePath History file path.
* @param int $retentionTime History content rentention time in seconds.
*
* @throws Exception if something goes wrong.
*/
public function __construct($historyFilePath, $retentionTime = null)
{
$this->historyFilePath = $historyFilePath;
if ($retentionTime !== null) {
$this->retentionTime = $retentionTime;
}
}
/**
* Initialize: read history file.
*
* Allow lazy loading (don't read the file if it isn't necessary).
*/
protected function initialize()
{
$this->check();
$this->read();
}
/**
* Add Event: new link.
*
* @param array $link Link data.
*/
public function addLink($link)
{
$this->addEvent(self::CREATED, $link['id']);
}
/**
* Add Event: update existing link.
*
* @param array $link Link data.
*/
public function updateLink($link)
{
$this->addEvent(self::UPDATED, $link['id']);
}
/**
* Add Event: delete existing link.
*
* @param array $link Link data.
*/
public function deleteLink($link)
{
$this->addEvent(self::DELETED, $link['id']);
}
/**
* Add Event: settings updated.
*/
public function updateSettings()
{
$this->addEvent(self::SETTINGS);
}
/**
* Save a new event and write it in the history file.
*
* @param string $status Event key, should be defined as constant.
* @param mixed $id Event item identifier (e.g. link ID).
*/
protected function addEvent($status, $id = null)
{
if ($this->history === null) {
$this->initialize();
}
$item = [
'event' => $status,
'datetime' => (new DateTime())->format(DateTime::ATOM),
'id' => $id !== null ? $id : '',
];
$this->history = array_merge([$item], $this->history);
$this->write();
}
/**
* Check that the history file is writable.
* Create the file if it doesn't exist.
*
* @throws Exception if it isn't writable.
*/
protected function check()
{
if (! is_file($this->historyFilePath)) {
FileUtils::writeFlatDB($this->historyFilePath, []);
}
if (! is_writable($this->historyFilePath)) {
throw new Exception('History file isn\'t readable or writable');
}
}
/**
* Read JSON history file.
*/
protected function read()
{
$this->history = FileUtils::readFlatDB($this->historyFilePath, []);
if ($this->history === false) {
throw new Exception('Could not parse history file');
}
}
/**
* Write JSON history file and delete old entries.
*/
protected function write()
{
$comparaison = new DateTime('-'. $this->retentionTime . ' seconds');
foreach ($this->history as $key => $value) {
if (DateTime::createFromFormat(DateTime::ATOM, $value['datetime']) < $comparaison) {
unset($this->history[$key]);
}
}
FileUtils::writeFlatDB($this->historyFilePath, array_values($this->history));
}
/**
* Get the History.
*
* @return array
*/
public function getHistory()
{
if ($this->history === null) {
$this->initialize();
}
return $this->history;
}
}