rss-bridge/lib/BridgeAbstract.php

434 lines
12 KiB
PHP

<?php
/**
* This file is part of RSS-Bridge, a PHP project capable of generating RSS and
* Atom feeds for websites that don't have one.
*
* For the full license information, please view the UNLICENSE file distributed
* with this source code.
*
* @package Core
* @license http://unlicense.org/ UNLICENSE
* @link https://github.com/rss-bridge/rss-bridge
*/
/**
* An abstract class for bridges
*
* This class implements {@see BridgeInterface} with most common functions in
* order to reduce code duplication. Bridges should inherit from this class
* instead of implementing the interface manually.
*
* @todo Move constants to the interface (this is supported by PHP)
* @todo Change visibility of constants to protected
* @todo Return `self` on more functions to allow chaining
* @todo Add specification for PARAMETERS ()
* @todo Add specification for $items
*/
abstract class BridgeAbstract implements BridgeInterface
{
/**
* Name of the bridge
*
* Use {@see BridgeAbstract::getName()} to read this parameter
*/
const NAME = 'Unnamed bridge';
/**
* URI to the site the bridge is intended to be used for.
*
* Use {@see BridgeAbstract::getURI()} to read this parameter
*/
const URI = '';
/**
* Donation URI to the site the bridge is intended to be used for.
*
* Use {@see BridgeAbstract::getDonationURI()} to read this parameter
*/
const DONATION_URI = '';
/**
* A brief description of what the bridge can do
*
* Use {@see BridgeAbstract::getDescription()} to read this parameter
*/
const DESCRIPTION = 'No description provided';
/**
* The name of the maintainer. Multiple maintainers can be separated by comma
*
* Use {@see BridgeAbstract::getMaintainer()} to read this parameter
*/
const MAINTAINER = 'No maintainer';
/**
* The default cache timeout for the bridge
*
* Use {@see BridgeAbstract::getCacheTimeout()} to read this parameter
*/
const CACHE_TIMEOUT = 3600;
/**
* Configuration for the bridge
*
* Use {@see BridgeAbstract::getConfiguration()} to read this parameter
*/
const CONFIGURATION = [];
/**
* Parameters for the bridge
*
* Use {@see BridgeAbstract::getParameters()} to read this parameter
*/
const PARAMETERS = [];
/**
* Test cases for detectParameters for the bridge
*/
const TEST_DETECT_PARAMETERS = [];
/**
* This is a convenient const for the limit option in bridge contexts.
* Can be inlined and modified if necessary.
*/
protected const LIMIT = [
'name' => 'Limit',
'type' => 'number',
'title' => 'Maximum number of items to return',
];
/**
* Holds the list of items collected by the bridge
*
* Items must be collected by {@see BridgeInterface::collectData()}
*
* Use {@see BridgeAbstract::getItems()} to access items.
*
* @var array
*/
protected $items = [];
/**
* Holds the list of input parameters used by the bridge
*
* Do not access this parameter directly!
* Use {@see BridgeAbstract::setInputs()} and {@see BridgeAbstract::getInput()} instead!
*
* @var array
*/
protected $inputs = [];
/**
* Holds the name of the queried context
*
* @var string
*/
protected $queriedContext = '';
/** {@inheritdoc} */
public function getItems()
{
return $this->items;
}
/**
* Sets the input values for a given context.
*
* @param array $inputs Associative array of inputs
* @param string $queriedContext The context name
* @return void
*/
protected function setInputs(array $inputs, $queriedContext)
{
// Import and assign all inputs to their context
foreach ($inputs as $name => $value) {
foreach (static::PARAMETERS as $context => $set) {
if (array_key_exists($name, static::PARAMETERS[$context])) {
$this->inputs[$context][$name]['value'] = $value;
}
}
}
// Apply default values to missing data
$contexts = [$queriedContext];
if (array_key_exists('global', static::PARAMETERS)) {
$contexts[] = 'global';
}
foreach ($contexts as $context) {
foreach (static::PARAMETERS[$context] as $name => $properties) {
if (isset($this->inputs[$context][$name]['value'])) {
continue;
}
$type = isset($properties['type']) ? $properties['type'] : 'text';
switch ($type) {
case 'checkbox':
if (!isset($properties['defaultValue'])) {
$this->inputs[$context][$name]['value'] = false;
} else {
$this->inputs[$context][$name]['value'] = $properties['defaultValue'];
}
break;
case 'list':
if (!isset($properties['defaultValue'])) {
$firstItem = reset($properties['values']);
if (is_array($firstItem)) {
$firstItem = reset($firstItem);
}
$this->inputs[$context][$name]['value'] = $firstItem;
} else {
$this->inputs[$context][$name]['value'] = $properties['defaultValue'];
}
break;
default:
if (isset($properties['defaultValue'])) {
$this->inputs[$context][$name]['value'] = $properties['defaultValue'];
}
break;
}
}
}
// Copy global parameter values to the guessed context
if (array_key_exists('global', static::PARAMETERS)) {
foreach (static::PARAMETERS['global'] as $name => $properties) {
if (isset($inputs[$name])) {
$value = $inputs[$name];
} elseif (isset($properties['defaultValue'])) {
$value = $properties['defaultValue'];
} else {
continue;
}
$this->inputs[$queriedContext][$name]['value'] = $value;
}
}
// Only keep guessed context parameters values
if (isset($this->inputs[$queriedContext])) {
$this->inputs = [$queriedContext => $this->inputs[$queriedContext]];
} else {
$this->inputs = [];
}
}
/**
* Set inputs for the bridge
*
* Returns errors and aborts execution if the provided input parameters are
* invalid.
*
* @param array List of input parameters. Each element in this list must
* relate to an item in {@see BridgeAbstract::PARAMETERS}
* @return void
*/
public function setDatas(array $inputs)
{
if (isset($inputs['context'])) { // Context hinting (optional)
$this->queriedContext = $inputs['context'];
unset($inputs['context']);
}
if (empty(static::PARAMETERS)) {
if (!empty($inputs)) {
returnClientError('Invalid parameters value(s)');
}
return;
}
$validator = new ParameterValidator();
if (!$validator->validateData($inputs, static::PARAMETERS)) {
$parameters = array_map(
function ($i) {
return $i['name'];
}, // Just display parameter names
$validator->getInvalidParameters()
);
returnClientError(
'Invalid parameters value(s): '
. implode(', ', $parameters)
);
}
// Guess the context from input data
if (empty($this->queriedContext)) {
$this->queriedContext = $validator->getQueriedContext($inputs, static::PARAMETERS);
}
if (is_null($this->queriedContext)) {
returnClientError('Required parameter(s) missing');
} elseif ($this->queriedContext === false) {
returnClientError('Mixed context parameters');
}
$this->setInputs($inputs, $this->queriedContext);
}
/**
* Loads configuration for the bridge
*
* Returns errors and aborts execution if the provided configuration is
* invalid.
*
* @return void
*/
public function loadConfiguration()
{
foreach (static::CONFIGURATION as $optionName => $optionValue) {
$configurationOption = Configuration::getConfig(get_class($this), $optionName);
if ($configurationOption !== null) {
$this->configuration[$optionName] = $configurationOption;
continue;
}
if (isset($optionValue['required']) && $optionValue['required'] === true) {
returnServerError(
'Missing configuration option: '
. $optionName
);
} elseif (isset($optionValue['defaultValue'])) {
$this->configuration[$optionName] = $optionValue['defaultValue'];
}
}
}
/**
* Returns the value for the provided input
*
* @param string $input The input name
* @return mixed|null The input value or null if the input is not defined
*/
protected function getInput($input)
{
if (!isset($this->inputs[$this->queriedContext][$input]['value'])) {
return null;
}
return $this->inputs[$this->queriedContext][$input]['value'];
}
/**
* Returns the value for the selected configuration
*
* @param string $input The option name
* @return mixed|null The option value or null if the input is not defined
*/
public function getOption($name)
{
if (!isset($this->configuration[$name])) {
return null;
}
return $this->configuration[$name];
}
/** {@inheritdoc} */
public function getDescription()
{
return static::DESCRIPTION;
}
/** {@inheritdoc} */
public function getMaintainer()
{
return static::MAINTAINER;
}
/** {@inheritdoc} */
public function getName()
{
return static::NAME;
}
/** {@inheritdoc} */
public function getIcon()
{
return static::URI . '/favicon.ico';
}
/** {@inheritdoc} */
public function getConfiguration()
{
return static::CONFIGURATION;
}
/** {@inheritdoc} */
public function getParameters()
{
return static::PARAMETERS;
}
/** {@inheritdoc} */
public function getURI()
{
return static::URI;
}
/** {@inheritdoc} */
public function getDonationURI()
{
return static::DONATION_URI;
}
/** {@inheritdoc} */
public function getCacheTimeout()
{
return static::CACHE_TIMEOUT;
}
/** {@inheritdoc} */
public function detectParameters($url)
{
$regex = '/^(https?:\/\/)?(www\.)?(.+?)(\/)?$/';
if (
empty(static::PARAMETERS)
&& preg_match($regex, $url, $urlMatches) > 0
&& preg_match($regex, static::URI, $bridgeUriMatches) > 0
&& $urlMatches[3] === $bridgeUriMatches[3]
) {
return [];
} else {
return null;
}
}
/**
* Loads a cached value for the specified key
*
* @param string $key Key name
* @param int $duration Cache duration (optional, default: 24 hours)
* @return mixed Cached value or null if the key doesn't exist or has expired
*/
protected function loadCacheValue($key, $duration = 86400)
{
$cacheFac = new CacheFactory();
$cache = $cacheFac->create();
$cache->setScope(get_called_class());
$cache->setKey($key);
if ($cache->getTime() < time() - $duration) {
return null;
}
return $cache->loadData();
}
/**
* Stores a value to cache with the specified key
*
* @param string $key Key name
* @param mixed $value Value to cache
*/
protected function saveCacheValue($key, $value)
{
$cacheFac = new CacheFactory();
$cache = $cacheFac->create();
$cache->setScope(get_called_class());
$cache->setKey($key);
$cache->saveData($value);
}
}