acquia_purge.module in Acquia Purge 6
Same filename and directory in other branches
Acquia Purge, Top-notch Varnish purging on Acquia Cloud!
File
acquia_purge.moduleView source
<?php
/**
* @file
* Acquia Purge, Top-notch Varnish purging on Acquia Cloud!
*/
/**
* The maximum number of paths to purge per batch step, this max will usually
* only be necessary on the command line where execution time is endless.
*/
define('ACQUIA_PURGE_MAX_PATHS', 20);
/**
* The maximum amount of HTTP requests that can be done per step. In practice
* this limited will be lowered to respect PHP's max execution time setting. It
* will be met when that setting is zero, e.g. on the command line.
*/
define('ACQUIA_PURGE_MAX_REQUESTS', 60);
/**
* The number of HTTP requests executed in parallel during purging.
*/
define('ACQUIA_PURGE_PARALLEL_REQUESTS', 6);
/**
* The number of seconds before a purge attempt times out.
*/
define('ACQUIA_PURGE_REQUEST_TIMEOUT', 2);
/**
* The amount of time in seconds used to lock purge processing.
*/
define('ACQUIA_PURGE_QUEUE_LOCK_TIMEOUT', 60);
/**
* Diagnostic severity levels: Informational.
*/
define('ACQUIA_PURGE_SEVLEVEL_INFO', -1);
/**
* Diagnostic severity levels: Good condition.
*/
define('ACQUIA_PURGE_SEVLEVEL_OK', 0);
/**
* Diagnostic severity levels: Warning condition, proceed but flag warning.
*/
define('ACQUIA_PURGE_SEVLEVEL_WARNING', 1);
/**
* Requirement severity: Error condition, do not purge items in the queue.
*/
define('ACQUIA_PURGE_SEVLEVEL_ERROR', 2);
/**
* Implements hook_init().
*/
function acquia_purge_init() {
// Abort loading the AJAX logic when hitting any of the excluded paths.
$excluded_auto_purging_paths = array(
'',
'admin/reports/status',
'admin/reports/dblog',
'acquia_purge_ajax_processor',
'media/browser',
'media/browser/testbed',
'media/browser/list',
'media/browser/library',
);
if (in_array($_GET['q'], $excluded_auto_purging_paths)) {
return;
}
// Detect if the current user instantiated a ongoing purge in the queues.
if (_acquia_purge_queue_is_user_purging()) {
// Trigger the client side candy so it starts doing its work.
_acquia_purge_trigger_client_side_purging();
}
}
/**
* Implements hook_perm().
*/
function acquia_purge_perm() {
return array(
'purge notification',
);
}
/**
* Implements hook_menu().
*/
function acquia_purge_menu() {
$items = array();
// Declare the hidden AJAX processor path which we call client side.
$items['acquia_purge_ajax_processor'] = array(
'title' => 'Acquia Purge AJAX processor',
'page callback' => 'acquia_purge_ajax_processor',
'access callback' => '_acquia_purge_queue_is_user_purging',
'file' => 'acquia_purge.admin.inc',
'type' => MENU_CALLBACK,
);
// Allow administrators to manually queue purge paths on the performance page.
$items['admin/settings/performance/manualpurge'] = array(
'type' => MENU_LOCAL_TASK,
'title' => 'Manually purge',
'page callback' => 'drupal_get_form',
'page arguments' => array(
'acquia_purge_manualpurge_form',
),
'access arguments' => array(
'administer site configuration',
),
'file' => 'acquia_purge.admin.inc',
'weight' => 40,
);
return $items;
}
/**
* Implements hook_expire_cache().
*/
function acquia_purge_expire_cache($paths) {
static $patterns;
// Ask our built-in diagnostics system to preliminary find issues that are so
// risky we can expect problems. Everything with ACQUIA_PURGE_SEVLEVEL_ERROR
// will cause purging to cease and we've got to tell the end user.
if (count($err = _acquia_purge_get_diagnosis(ACQUIA_PURGE_SEVLEVEL_ERROR))) {
// Stack all found error messages (can be one too) in a HTML item list.
$items = array();
foreach ($err as $error) {
$items[] = '<p>' . $error['description'] . '</p>';
}
$items = theme('item_list', array(
'items' => $items,
));
// Warn the user on-screen that purging cannot continue.
if (user_access('purge notification')) {
drupal_set_message(t("<p>The system cannot publicly refresh the changes you just made,\n because of the following error conditions:</p>!items<p>Please\n contact your system administrator or development partner!</p>", array(
'!items' => $items,
)), 'warning');
}
else {
_acquia_purge_get_diagnosis_logged($err);
}
return;
}
// The expire module is unreliable API-wise as it often gives absolute URLs
// in various scenarios. In the past we tested for 'expire_include_base_url'
// but that doesn't always seem to help. We therefore generate a list of
// possible http://domainname patterns to strip out. D.o: #2049235, #2133001.
$schemes = array(
'http://',
'https://',
);
if (is_null($patterns)) {
foreach (_acquia_purge_get_domains() as $domain) {
foreach ($schemes as $scheme) {
$patterns[] = "{$scheme}{$domain}" . base_path();
$patterns[] = "{$scheme}{$domain}";
}
}
}
// Iterate the given paths and strip everything out we can think off.
$new_paths = array();
foreach ($paths as $path) {
foreach ($patterns as $pattern) {
$path = str_replace($pattern, '', $path);
}
$path = ltrim($path, '/');
if (!in_array($path, $new_paths)) {
$new_paths[] = $path;
}
}
$paths = $new_paths;
// This should help for many cases, but not always. Detect if any of the paths
// still contain http:// or https://.
$paths_clean = TRUE;
foreach ($paths as $path) {
if (!$paths_clean) {
break;
}
foreach ($schemes as $scheme) {
if (strpos($path, $scheme) !== FALSE) {
$paths_clean = FALSE;
break;
}
}
}
// If the "cleaned" paths are still dirty we warn the user and abort purging.
if (!$paths_clean) {
drupal_set_message(t("Please disable the 'Include base URL in expires'\n setting as it is incompatible with the Acquia Purge module. "), 'error');
}
else {
acquia_purge_purge_paths($paths);
}
}
/**
* Implements hook_theme().
*/
function acquia_purge_theme($existing, $type, $theme, $path) {
return array(
'acquia_purge_status_bar_widget' => array(
'variables' => array(
'total' => 0,
'remaining' => 0,
'processed' => 0,
'percent' => 100,
'running' => FALSE,
'purgehistory' => array(),
),
'file' => 'acquia_purge.admin.inc',
),
'acquia_purge_status_widget' => array(
'variables' => array(
'total' => 0,
'remaining' => 0,
'processed' => 0,
'percent' => 100,
'running' => FALSE,
'purgehistory' => array(),
),
'file' => 'acquia_purge.admin.inc',
),
);
}
/**
* Determine whether we are running on Acquia Cloud or not.
*
* @returns
* A boolean expression indicating if we currently run on Acquia cloud.
*/
function _acquia_purge_are_we_on_acquiacloud() {
static $connected;
// Build our assertions logic and cache it statically.
if (is_null($connected)) {
$assertions = array(
is_array(variable_get('acquia_hosting_site_info', FALSE)),
(bool) count(_acquia_purge_get_balancers()),
(bool) _acquia_purge_get_site_name(),
(bool) _acquia_purge_get_site_group(),
function_exists('curl_init'),
);
$connected = !in_array(FALSE, $assertions);
}
return $connected;
}
/**
* Turn a PHP variable into a string with data type information for debugging.
*
* @param mixed $symbols
* Arbitrary PHP variable, preferably a associative array.
*
* @returns
* A one-line comma separated string with data types as var_dump() generates.
*/
function _acquia_purge_export_debug_symbols($symbols) {
// Capture a string using PHPs very own var_dump() using output buffering.
ob_start();
var_dump($symbols);
$symbols = ob_get_clean();
// Clean up and reduce the output footprint for both normal and xdebug output.
if (extension_loaded('xdebug')) {
$symbols = trim(html_entity_decode(strip_tags($symbols)));
$symbols = drupal_substr($symbols, strpos($symbols, "\n") + 1);
$symbols = str_replace(" '", '', $symbols);
$symbols = str_replace("' =>", ':', $symbols);
$symbols = implode(', ', explode("\n", $symbols));
}
else {
$symbols = strip_tags($symbols);
$symbols = drupal_substr($symbols, strpos($symbols, "\n") + 1);
$symbols = str_replace(' ["', '', $symbols);
$symbols = str_replace("\"]=>\n ", ':', $symbols);
$symbols = rtrim($symbols, "}\n");
$symbols = implode(', ', explode("\n", $symbols));
}
// To reduce bandwidth and storage needs we shorten data type indicators.
$symbols = str_replace(' string', 'S', $symbols);
$symbols = str_replace(' int', 'I', $symbols);
$symbols = str_replace(' float', 'F', $symbols);
$symbols = str_replace(' boolean', 'B', $symbols);
$symbols = str_replace(' bool', 'B', $symbols);
$symbols = str_replace(' null', 'NLL', $symbols);
$symbols = str_replace(' NULL', 'NLL', $symbols);
$symbols = str_replace('length=', 'l=', $symbols);
// Return the resulting string.
return $symbols;
}
/**
* Get a list of load balancer IP addresses in front of this Acquia Cloud site.
*
* @warning
* Please note that the returned IP addresses are internal addresses.
*
* @returns
* Array with string values pointing to every Acquia Cloud load balancer.
*/
function _acquia_purge_get_balancers() {
static $balancers;
// Cache the results statically, preventing multiple lookups during runtime.
if (is_null($balancers)) {
$balancers = array();
foreach (variable_get('reverse_proxies', array()) as $ip_address) {
$balancers[] = $ip_address;
}
}
return $balancers;
}
/**
* Perform a series of self-tests against the site and our purging conditions.
*
* @param int $verbosity
* Optional, the level of diagnostics presented. Test results that match or
* are higher than the given level are returned.
*
* @returns
* Array that complies to the format as seen in hook_requirements().
*/
function _acquia_purge_get_diagnosis($verbosity = ACQUIA_PURGE_SEVLEVEL_INFO) {
static $tests;
// Initialize $tests and gather test results, cache everything statically.
if (is_null($tests)) {
$module_path = drupal_get_path('module', 'acquia_purge');
$prefix = '_acquia_purge_get_diagnosis_';
$tests = array();
$t = get_t();
// Require the file that contains our tests: acquia_purge.diagnostics.inc.
require_once $module_path . '/acquia_purge.diagnostics.inc';
// Similar to hooks, functions starting with "_acquia_purge_get_diagnosis_"
// will be regarded as individual tests and called to gather results.
$functions = get_defined_functions();
foreach ($functions['user'] as $function) {
if ($function === '_acquia_purge_get_diagnosis_logged') {
continue;
}
elseif (strpos($function, $prefix) !== 0) {
continue;
}
// Add the test and its resulting data to the tests array.
$tst = str_replace($prefix, 'acquia_purge_', $function);
$tests[$tst] = $function($t);
// Overwrite or assure data integrity on most of the fields.
$tests[$tst]['name'] = isset($tests[$tst]['title']) ? $tests[$tst]['title'] : $tst;
$tests[$tst]['description'] = isset($tests[$tst]['description']) ? $tests[$tst]['description'] : NULL;
$tests[$tst]['description_plain'] = strip_tags($tests[$tst]['description']);
$tests[$tst]['severity'] = isset($tests[$tst]['severity']) ? $tests[$tst]['severity'] : ACQUIA_PURGE_SEVLEVEL_INFO;
$tests[$tst]['value_plain'] = isset($tests[$tst]['value_plain']) ? $tests[$tst]['value_plain'] : $tests[$tst]['value'];
$tests[$tst]['value_plain'] = $t('@title: @value', array(
'@title' => $tests[$tst]['title'],
'@value' => $tests[$tst]['value_plain'],
));
$tests[$tst]['value'] = $t('<b>@title</b><br />@value', array(
'@title' => $tests[$tst]['title'],
'@value' => $tests[$tst]['value'],
));
$tests[$tst]['title'] = $t('Acquia Purge');
}
}
// Return test results that match or are higher than the verbosity level.
$results = array();
foreach ($tests as $name => $result) {
if ($result['severity'] >= $verbosity) {
$results[$name] = $result;
}
}
return $results;
}
/**
* Log diagnostic test results to watchdog.
*
* @param array $items
* Associative array with test results or an individual test result array.
*
* @see _acquia_purge_get_diagnosis()
* @returns
* Void,
*/
function _acquia_purge_get_diagnosis_logged($items) {
$severitymap = array(
ACQUIA_PURGE_SEVLEVEL_INFO => WATCHDOG_INFO,
ACQUIA_PURGE_SEVLEVEL_OK => WATCHDOG_INFO,
ACQUIA_PURGE_SEVLEVEL_WARNING => WATCHDOG_ERROR,
ACQUIA_PURGE_SEVLEVEL_ERROR => WATCHDOG_CRITICAL,
);
// Wrap single a single test result into a workable array.
if (isset($items['severity'])) {
$items = array(
$items,
);
}
// Iterate the items and report them to the watchdog log.
foreach ($items as $item) {
$description = $item['description_plain'];
if (empty($description)) {
$description = $item['value_plain'];
}
watchdog('acquia_purge', $description, array(), $severitymap[$item['severity']]);
}
}
/**
* Get a list of defined domains that we can purge for.
*
* @returns
* Array with string values mapping to all defined DNS domains for this site.
*/
function _acquia_purge_get_domains() {
static $domains;
// Statically cache the domains as fetching them once per request is enough.
if (is_null($domains)) {
$domains = array();
// If the configuration key 'acquia_purge_domains' is set we skip automatic
// detection fully and add that list of domains to be purged.
if ($acquia_purge_domains = variable_get('acquia_purge_domains', FALSE)) {
if (is_array($acquia_purge_domains) && count($acquia_purge_domains)) {
foreach ($acquia_purge_domains as $domain) {
_acquia_purge_get_domains_add($domain, $domains);
}
// Set and return the set of hardcoded domains.
return $domains;
}
}
// Add the current HTTP_HOST that we're connected to.
_acquia_purge_get_domains_add($_SERVER['HTTP_HOST'], $domains);
// Strip an empty absolute URL (which respects $base_url) and make sure
// that domain is also in the list of domains to be purged.
$base_domain = url('', array(
'absolute' => TRUE,
));
$base_domain = str_replace('https://', '', $base_domain);
$base_domain = str_replace('http://', '', $base_domain);
$base_domain = str_replace(base_path(), '', $base_domain);
_acquia_purge_get_domains_add($base_domain, $domains);
// To better support multi-sites we only load in the configured Acquia Cloud
// domain names when we are on the 'default' site as that would else flood
// another site which we don't want to happen, on <front> for example.
if (conf_path() == 'sites/default') {
// Add the domain names the customer defined on Acquia Cloud. When this
// process would fail we have at least the current + $base_url domain.
if (_acquia_purge_are_we_on_acquiacloud()) {
_acquia_purge_get_domains_add_acloud($domains);
}
}
}
return $domains;
}
/**
* Add a domain to the domain list after cleaning and checking for duplicates.
*
* @param string $domain
* The domain string to be added to the list.
* @param array &$domains
* A reference to the array of currently gathered domain names.
*
* @returns
* Void, data will be added by reference.
*/
function _acquia_purge_get_domains_add($domain, &$domains) {
$domain = trim(drupal_strtolower($domain));
if (!empty($domain) && !in_array($domain, $domains)) {
$domains[] = $domain;
}
}
/**
* Expand the list of domains being gathered by those defined in Acquia Cloud.
*
* @param array $domains
* A reference to the array of currently gathered domain names.
*
* @returns
* Void, data will be added by reference.
* @warning
* The current implementation of this function is subject to change. @TODO
*/
function _acquia_purge_get_domains_add_acloud(&$domains) {
$detected_domains = array();
// This implementation is very dirty, admitted. Only possible way as of this
// writing as there is no API level exposure of it. These files are generated
// automatically so risks of changes are small.
if (file_exists('/etc/apache2/conf.d')) {
$site_name = _acquia_purge_get_site_name();
$server_name = shell_exec("grep -r 'ServerName' /etc/apache2/conf.d/{$site_name}*.conf");
foreach (explode('ServerName', $server_name) as $testable) {
foreach (explode(' ', trim($testable)) as $domain) {
$detected_domains[] = $domain;
}
}
$server_alias = shell_exec("grep -r 'ServerAlias' /etc/apache2/conf.d/{$site_name}*.conf");
foreach (explode('ServerAlias', $server_alias) as $testable) {
foreach (explode(' ', trim($testable)) as $domain) {
$detected_domains[] = $domain;
}
}
}
// Remove the acquia-sites.com domain if we have found more then 1 domain. The
// less domains found, the faster the end user experience will be.
if (count($detected_domains) > 1) {
foreach ($detected_domains as $i => $detected_domain) {
if (strpos($detected_domain, 'acquia-sites.com') !== FALSE) {
unset($detected_domains[$i]);
}
}
}
// Register all detected domain names.
foreach ($detected_domains as $i => $detected_domain) {
_acquia_purge_get_domains_add($detected_domain, $domains);
}
}
/**
* Get a list of protocol schemes that will be purged.
*
* @warning
* This facilitates future functionality, currently only HTTP is supported.
*
* @returns
* Array with scheme strings like 'http' and 'https'.
*/
function _acquia_purge_get_protocol_schemes() {
return array(
'http',
);
}
/**
* Determine the Acquia site name.
*
* @returns
* Either a boolean FALSE or a string identifying what site we are on.
*/
function _acquia_purge_get_site_name() {
static $ah_site_name;
if (is_null($ah_site_name)) {
$ah_site_name = FALSE;
if (isset($_ENV['AH_SITE_NAME']) && !empty($_ENV['AH_SITE_NAME'])) {
$ah_site_name = $_ENV['AH_SITE_NAME'];
}
}
return $ah_site_name;
}
/**
* Determine the Acquia site group.
*
* @returns
* Either a boolean FALSE or a string identifying what site group this is.
*/
function _acquia_purge_get_site_group() {
static $ah_site_group;
if (is_null($ah_site_group)) {
$ah_site_group = FALSE;
if (isset($_ENV['AH_SITE_GROUP']) && !empty($_ENV['AH_SITE_GROUP'])) {
$ah_site_group = $_ENV['AH_SITE_GROUP'];
}
}
return $ah_site_group;
}
/**
* Queue manager: add a single purge to the queue.
*
* @param string $path
* The Drupal path (e.g. '<front>', 'user/1' or an aliased path).
*
* @returns
* The total amount of items in the queue (int).
*/
function _acquia_purge_queue_add($path) {
$qcount = variable_get('acquia_purge_queue_counter', 0);
// Add the non-associative purge item definition.
db_query("INSERT INTO {ap_queue} (path) VALUES ('%s')", $path);
// Bump the queue counter.
$qcount++;
// Register the currently logged on user as one of the queue owners. These
// users are given the AJAX client side script until the queue is empty.
static $owner_registered;
if (is_null($owner_registered) && php_sapi_name() != 'cli') {
global $user;
// Only register authenticated users, anonymous users will only queue.
if (isset($user->roles[DRUPAL_AUTHENTICATED_RID])) {
$owners = variable_get('acquia_purge_queue_owners', array());
if (!in_array($user->name, $owners)) {
$owners[] = $user->name;
variable_set('acquia_purge_queue_owners', $owners);
}
$owner_registered = TRUE;
}
}
// Store the queue counter in our state variable.
variable_set('acquia_purge_queue_counter', $qcount);
return $qcount;
}
/**
* Queue manager: clear the queue and invalidate all running processes.
*
* @returns
* Void.
*/
function _acquia_purge_queue_clear() {
db_query('DELETE FROM {ap_queue}');
variable_set('acquia_purge_queue_counter', 0);
variable_set('acquia_purge_queue_owners', array());
}
/**
* Queue manager: pop X amount of items from the queue.
*
* @param string $processor_callback
* The name of a PHP function or callable that gets called to process a
* individual item popped from the queue. The callback is given the path as
* argument. This parameter is optional.
*
* @warning
* Calling this helper commits the caller into actually processing the items
* popped from the queue, either by iterating the return value or by providing
* a processing callback that processes individual values. Not processing the
* result will lead into confusion and broken functionality.
* @returns
* Non-associative array of which every value record represents one resulting
* HTTP PURGE request. Array items are non-associative arrays itself with the
* path in key #0.
*/
function _acquia_purge_queue_pop($processor_callback = NULL) {
$items = array();
// Determine the maximum amount of requests that we can process at once.
$max_execution_time = (int) ini_get('max_execution_time');
$max_requests = ACQUIA_PURGE_MAX_REQUESTS;
if ($max_execution_time != 0) {
// Never take more then 80% of all available execution time.
$max_execution_time = intval(0.8 * $max_execution_time);
$max_requests = $max_execution_time / ACQUIA_PURGE_REQUEST_TIMEOUT;
$max_requests = ACQUIA_PURGE_PARALLEL_REQUESTS * $max_requests;
if ($max_requests > ACQUIA_PURGE_MAX_REQUESTS) {
$max_requests = ACQUIA_PURGE_MAX_REQUESTS;
}
}
// Calculate the amount of paths to pop from the queue based on how many HTTP
// requests we are going to generate and how much we can maximally process.
$balancers = count(_acquia_purge_get_balancers());
$domains = count(_acquia_purge_get_domains());
$schemes = count(_acquia_purge_get_protocol_schemes());
$requests = $schemes * ($domains * $balancers);
$paths = intval($max_requests / $requests);
// In scenarios with many balancers or many domains it might happen that even
// one path will trigger more HTTP requests than we can handle. To prevent
// not purging anything anymore we will attempt one but with taking risks.
if ($paths < 1) {
$paths = 1;
}
// Limit the number of paths to pop when it maxed out the set limit. Usually
// only happens on the command line.
if ($paths > ACQUIA_PURGE_MAX_PATHS) {
$paths = ACQUIA_PURGE_MAX_PATHS;
}
// Retrieve the amount of paths that we just calculated we could handle.
$items_to_be_removed = array();
$itemsq = db_query("SELECT * FROM {ap_queue} LIMIT %d", $paths);
while ($item = db_fetch_object($itemsq)) {
// Add this item to the items list released back or being processed.
$items[] = array(
$item->path,
);
// Call the callback once provided and pass on the arguments to purge.
if (!is_null($processor_callback)) {
// If the processor throws FALSE: release the item and try again later.
if (call_user_func_array($processor_callback, array(
$item->path,
))) {
$items_to_be_removed[] = $item->item_id;
}
}
else {
$items_to_be_removed[] = $item->item_id;
}
}
// Remove the items that we're listed as safe to be removed from the queue.
if (count($items_to_be_removed)) {
$ids = implode(',', $items_to_be_removed);
db_query('DELETE FROM {ap_queue} WHERE item_id IN (' . $ids . ')');
}
// Set acquia_purge_queue_counter to 0 once the queue is empty as well.
if ((int) db_result(db_query("SELECT COUNT(*) FROM {ap_queue}")) === 0) {
// Once its back to 0, progress is 100% and no activity is assumed.
variable_set('acquia_purge_queue_counter', 0);
variable_set('acquia_purge_queue_owners', array());
}
return $items;
}
/**
* Queue manager: process a single path (on all domains and balancers).
*
* @param string $path
* The Drupal path (e.g. '<front>', 'user/1' or an aliased path).
*
* @returns
* Boolean TRUE/FALSE indicating success or failure of the attempt.
*/
function _acquia_purge_queue_processpurge($path) {
$base_path = base_path();
// Ask our built-in diagnostics system to preliminary find issues that are so
// risky we can expect problems. Everything with ACQUIA_PURGE_SEVLEVEL_ERROR
// will cause purging to cease and log messages to be written. Because we
// return FALSE, the queued items will be purged later in better weather.
if (count($err = _acquia_purge_get_diagnosis(ACQUIA_PURGE_SEVLEVEL_ERROR))) {
_acquia_purge_get_diagnosis_logged($err);
return FALSE;
}
// Rewrite '<front>' to a empty string, which will be the frontpage. By using
// substr() and str_replace() we still allow cases like '<front>?param=1'.
if (drupal_substr($path, 0, 7) === '<front>') {
$path = str_replace('<front>', '', $path);
}
// Because a single path can exist on http://, https://, on various domain
// names and could be cached on any of the known load balancers. Therefore we
// define a list of HTTP requests that we are going to fire in a moment.
$requests = array();
foreach (_acquia_purge_get_balancers() as $balancer_ip) {
foreach (_acquia_purge_get_domains() as $domain) {
foreach (_acquia_purge_get_protocol_schemes() as $scheme) {
$rqst = new stdClass();
$rqst->scheme = $scheme;
$rqst->rtype = 'PURGE';
$rqst->balancer = $balancer_ip;
$rqst->domain = $domain;
$rqst->path = str_replace('//', '/', $base_path . $path);
$rqst->uri = $rqst->scheme . '://' . $rqst->domain . $rqst->path;
$rqst->uribal = $rqst->scheme . '://' . $rqst->balancer . $rqst->path;
$rqst->headers = array(
'Host: ' . $rqst->domain,
'Accept-Encoding: gzip',
'X-Acquia-Purge: ' . _acquia_purge_get_site_name(),
);
$requests[] = $rqst;
}
}
}
// Before we issue these purges against the load balancers we ensure that any
// of these URLs are not left cached in Drupal's ordinary page cache.
$already_cleared = array();
foreach ($requests as $rqst) {
if (!in_array($rqst->uri, $already_cleared)) {
cache_clear_all($rqst->uri, 'cache_page');
$already_cleared[] = $rqst->uri;
}
}
// Execute the prepared requests efficiently and log their results.
$overall_success = TRUE;
foreach (_acquia_purge_queue_processpurge_requests($requests) as $rqst) {
if ($rqst->result == TRUE) {
watchdog('acquia_purge', "Purged '%url' from load balancer %balancer.", array(
'%url' => $rqst->uri,
'%balancer' => $rqst->balancer,
), WATCHDOG_INFO);
_acquia_purge_queue_stats($rqst->uri);
}
else {
if ($overall_success) {
$overall_success = FALSE;
}
// Log the failing attempt and include verbose debugging information.
watchdog('acquia_purge', "Failed attempt to purge '%url' from load balancer %balancer for " . "unknown reasons as curl failed. The path item is re-queued! " . "Debugging symbols: '%debug',", array(
'%url' => $rqst->uri,
'%balancer' => $rqst->balancer,
'%debug' => $rqst->error_debug,
), WATCHDOG_ERROR);
}
}
// If one the many HTTP requests failed we treat the full path as a failure,
// by sending back FALSE the item will remain in the queue. Failsafe style.
return $overall_success;
}
/**
* Queue manager: process the given HTTP requests and do it efficiently.
*
* @param string $requests
* Unassociative array (list) of simple Stdclass objects with the following
* properties: scheme, rtype, server, domain, path, uri, uribal.
*
* @returns
* The given requests array with added properties that describe the result of
* the request: 'result', 'error_curl', 'error_http', 'error_debug'.
*/
function _acquia_purge_queue_processpurge_requests($requests) {
$single_mode = count($requests) === 1;
$results = array();
// Initialize the cURL multi handler.
if (!$single_mode) {
static $curl_multi;
if (is_null($curl_multi)) {
$curl_multi = curl_multi_init();
}
}
// Enter our event loop and keep on requesting until $unprocessed is empty.
$unprocessed = count($requests);
while ($unprocessed > 0) {
// Group requests per sets that we can run in parallel.
for ($i = 0; $i < ACQUIA_PURGE_PARALLEL_REQUESTS; $i++) {
if ($rqst = array_shift($requests)) {
$rqst->curl = curl_init();
// Instantiate the cURL resource and configure its runtime parameters.
curl_setopt($rqst->curl, CURLOPT_URL, $rqst->uribal);
curl_setopt($rqst->curl, CURLOPT_TIMEOUT, ACQUIA_PURGE_REQUEST_TIMEOUT);
curl_setopt($rqst->curl, CURLOPT_HTTPHEADER, $rqst->headers);
curl_setopt($rqst->curl, CURLOPT_CUSTOMREQUEST, $rqst->rtype);
curl_setopt($rqst->curl, CURLOPT_FAILONERROR, TRUE);
// Add our handle to the multiple cURL handle.
if (!$single_mode) {
curl_multi_add_handle($curl_multi, $rqst->curl);
}
// Add the shifted request to the results array and change the counter.
$results[] = $rqst;
$unprocessed--;
}
}
// Execute the created handles in parallel.
if (!$single_mode) {
$active = NULL;
do {
$mrc = curl_multi_exec($curl_multi, $active);
} while ($mrc == CURLM_CALL_MULTI_PERFORM);
while ($active && $mrc == CURLM_OK) {
if (curl_multi_select($curl_multi) != -1) {
do {
$mrc = curl_multi_exec($curl_multi, $active);
} while ($mrc == CURLM_CALL_MULTI_PERFORM);
}
}
}
else {
curl_exec($results[0]->curl);
$single_info = array(
'result' => curl_errno($results[0]->curl),
);
}
// Iterate the set of results and fetch cURL result and resultcodes. Only
// process those with the 'curl' property as the property will be removed.
foreach ($results as $i => $rqst) {
if (!isset($rqst->curl)) {
continue;
}
$info = $single_mode ? $single_info : curl_multi_info_read($curl_multi);
$results[$i]->result = $info['result'] == CURLE_OK ? TRUE : FALSE;
$results[$i]->error_curl = $info['result'];
$results[$i]->error_http = curl_getinfo($rqst->curl, CURLINFO_HTTP_CODE);
// When the result failed but the HTTP code is 404 we turn the result
// into a TRUE as Varnish simply couldn't find the entry as its not there.
if (!$results[$i]->result && $results[$i]->error_http == 404) {
$results[$i]->result = TRUE;
}
// Collect debugging information if necessary.
$results[$i]->error_debug = '';
if (!$results[$i]->result) {
$debug = curl_getinfo($rqst->curl);
$debug['headers'] = implode('|', $rqst->headers);
unset($debug['certinfo']);
$results[$i]->error_debug = _acquia_purge_export_debug_symbols($debug);
}
// Remove the handle if parallel processing occurred.
if (!$single_mode) {
curl_multi_remove_handle($curl_multi, $rqst->curl);
}
// Close the resource and delete its property.
curl_close($rqst->curl);
unset($rqst->curl);
}
}
return $results;
}
/**
* Queue manager: generate progress statistics on the purge queue.
*
* @param string $log_purged_url
* This optional parameter allows purge processors to record URLs that got
* purged successfully during runtime context. This facility is not persistent
* trough requests and only intended for GUI elements and statistics.
*
* @returns
* Associative array with the keys 'running', 'total', 'remaining',
* 'processed', 'percent' and 'purgehistory'.
*/
function _acquia_purge_queue_stats($log_purged_url = FALSE) {
// Initialize the $purgehistory runtime log and add a extra path if provided.
static $purgehistory;
if (is_null($purgehistory)) {
$purgehistory = array();
}
if ($log_purged_url) {
if (!in_array($log_purged_url, $purgehistory)) {
$purgehistory[] = $log_purged_url;
}
}
// Initialize array with default values, except for the total counter.
$info = array(
'total' => variable_get('acquia_purge_queue_counter', 0),
'remaining' => 0,
'processed' => 0,
'percent' => 100,
'running' => FALSE,
'purgehistory' => $purgehistory,
);
// Cut statistics gathering when the queue counter equals 0: not running.
if ($info['total'] === 0) {
return $info;
}
// Once we are here there are jobs running, lets update that.
$info['running'] = TRUE;
// Add 'remaining' and 'processed' counters.
$info['remaining'] = db_query("SELECT COUNT(*) FROM {ap_queue}");
$info['remaining'] = (int) db_result($info['remaining']);
$info['processed'] = $info['total'] - $info['remaining'];
// Calculate the percentage of the job.
$info['percent'] = $info['remaining'] / $info['total'] * 100;
$info['percent'] = (int) (100 - floor($info['percent']));
return $info;
}
/**
* Queue manager: determines if the current owns a running purge session.
*
* @see _acquia_purge_queue_add()
* @returns
* Boolean TRUE when the current user with the exact same session initiated
* a purge session earlier and thus owns the purge session.
*/
function _acquia_purge_queue_is_user_purging() {
global $user;
// Anonymous users are never able to trigger purges by design, if this would
// ever become a necessity we'll introduce a permission to protect most sites.
if (!isset($user->roles[DRUPAL_AUTHENTICATED_RID])) {
return FALSE;
}
// Retrieve the list of user names owning a ongoing purge process.
$owners = variable_get('acquia_purge_queue_owners', array());
// If the owners list is empty, that means no active purges are ongoing.
if (!count($owners)) {
return FALSE;
}
// Is the current user one of the owners of the actively ongoing purge?
if (!in_array($user->name, $owners)) {
return FALSE;
}
// Are we running on a Acquia Cloud environment?
if (!_acquia_purge_are_we_on_acquiacloud()) {
return FALSE;
}
// All tests passed, this user can process the queue.
return TRUE;
}
/**
* Trigger client-side AJAX based purging during this request.
*
* @returns
* Void, this function doesn't return anything.
*/
function _acquia_purge_trigger_client_side_purging() {
// Prevent API misuse and don't trigger when this user doesn't own the queue.
if (!_acquia_purge_queue_is_user_purging()) {
return;
}
// Load the JQuery logic that will start hitting 'acquia_purge_ajax_processor'
// which on its turn will process the queue. Because the back-end uses locks
// we don't have to worry about how many times we're hitting it. When the user
// doesn't have on-screen reporting enabled the HTML DIV won't be present
// causing the script to simply purge silently without notifying the user.
$module_path = drupal_get_path('module', 'acquia_purge');
drupal_add_js($module_path . '/acquia_purge.js');
// If the user has the permission 'purge notification' it means on-screen
// reporting is enabled and we'll set a standard drupal_set_message() that
// announces the AJAX powered purging. Because we're abusing the API with a
// non-standard message type our JQuery logic is smartly able to replace the
// nodes with the interactive progressbar.
if (user_access('purge notification')) {
$message = t("There have been changes to content, and these needs to be\n refreshed throughout the system. There may be a delay before the changes\n appear to all website visitors.");
// Set the message and don't repeat it if it is already set.
drupal_set_message($message, 'acquia_purge_messages', FALSE);
// Add inline CSS to initially hide the message (see d.o. 2014461). A
// separate file that could be cached would be non-sense for this one line
// declaration as this statement only occurs for authenticated users.
drupal_add_css($module_path . '/acquia_purge.css');
}
}
/**
* Purge the paths from a node from Varnish.
*
* @param object $node
* A Drupal node object that was just inserted or saved.
*
* @returns
* Progress statistics from the queue manager. Associative array with the keys
* 'running', 'total', 'remaining', 'processed', 'percent' and 'purgehistory'.
*/
function acquia_purge_purge_node(&$node) {
$paths = array(
'node/' . $node->nid,
);
if (isset($node->path['alias']) && !empty($node->path['alias'])) {
$paths[] = $node->path['alias'];
}
if (isset($node->promote) && $node->promote) {
$paths[] = '<front>';
$paths[] = 'rss.xml';
}
// Return the paths routine and return the statistics from the queue manager.
return acquia_purge_purge_paths($paths);
}
/**
* Purge a certain Drupal path from Varnish.
*
* @param string $path
* The Drupal path (e.g. '<front>', 'user/1' or an aliased path).
*
* @returns
* Progress statistics from the queue manager. Associative array with the keys
* 'running', 'total', 'remaining', 'processed', 'percent' and 'purgehistory'.
*/
function acquia_purge_purge_path($path) {
// Queue the path.
_acquia_purge_queue_add($path);
// Return the statistics array based returning useful information about the
// current state of the purge queue.
return _acquia_purge_queue_stats();
}
/**
* Purge a several Drupal paths from Varnish.
*
* @param string $paths
* Array with Drupal paths (e.g. '<front>', 'user/1' or an aliased path).
*
* @returns
* Progress statistics from the queue manager. Associative array with the keys
* 'running', 'total', 'remaining', 'processed', 'percent' and 'purgehistory'.
*/
function acquia_purge_purge_paths($paths) {
// Dispatch the paths to acquia_purge_purge_path().
foreach ($paths as $path) {
// Add the item to the queue.
_acquia_purge_queue_add($path);
}
// Return the statistics array based returning useful information about the
// current state of the purge queue.
return _acquia_purge_queue_stats();
}Functions
Name |
Description |
|---|---|
| acquia_purge_expire_cache | Implements hook_expire_cache(). |
| acquia_purge_init | Implements hook_init(). |
| acquia_purge_menu | Implements hook_menu(). |
| acquia_purge_perm | Implements hook_perm(). |
| acquia_purge_purge_node | Purge the paths from a node from Varnish. |
| acquia_purge_purge_path | Purge a certain Drupal path from Varnish. |
| acquia_purge_purge_paths | Purge a several Drupal paths from Varnish. |
| acquia_purge_theme | Implements hook_theme(). |
| _acquia_purge_are_we_on_acquiacloud | Determine whether we are running on Acquia Cloud or not. |
| _acquia_purge_export_debug_symbols | Turn a PHP variable into a string with data type information for debugging. |
| _acquia_purge_get_balancers | Get a list of load balancer IP addresses in front of this Acquia Cloud site. |
| _acquia_purge_get_diagnosis | Perform a series of self-tests against the site and our purging conditions. |
| _acquia_purge_get_diagnosis_logged | Log diagnostic test results to watchdog. |
| _acquia_purge_get_domains | Get a list of defined domains that we can purge for. |
| _acquia_purge_get_domains_add | Add a domain to the domain list after cleaning and checking for duplicates. |
| _acquia_purge_get_domains_add_acloud | Expand the list of domains being gathered by those defined in Acquia Cloud. |
| _acquia_purge_get_protocol_schemes | Get a list of protocol schemes that will be purged. |
| _acquia_purge_get_site_group | Determine the Acquia site group. |
| _acquia_purge_get_site_name | Determine the Acquia site name. |
| _acquia_purge_queue_add | Queue manager: add a single purge to the queue. |
| _acquia_purge_queue_clear | Queue manager: clear the queue and invalidate all running processes. |
| _acquia_purge_queue_is_user_purging | Queue manager: determines if the current owns a running purge session. |
| _acquia_purge_queue_pop | Queue manager: pop X amount of items from the queue. |
| _acquia_purge_queue_processpurge | Queue manager: process a single path (on all domains and balancers). |
| _acquia_purge_queue_processpurge_requests | Queue manager: process the given HTTP requests and do it efficiently. |
| _acquia_purge_queue_stats | Queue manager: generate progress statistics on the purge queue. |
| _acquia_purge_trigger_client_side_purging | Trigger client-side AJAX based purging during this request. |
Constants
|
Name |
Description |
|---|---|
| ACQUIA_PURGE_MAX_PATHS | The maximum number of paths to purge per batch step, this max will usually only be necessary on the command line where execution time is endless. |
| ACQUIA_PURGE_MAX_REQUESTS | The maximum amount of HTTP requests that can be done per step. In practice this limited will be lowered to respect PHP's max execution time setting. It will be met when that setting is zero, e.g. on the command line. |
| ACQUIA_PURGE_PARALLEL_REQUESTS | The number of HTTP requests executed in parallel during purging. |
| ACQUIA_PURGE_QUEUE_LOCK_TIMEOUT | The amount of time in seconds used to lock purge processing. |
| ACQUIA_PURGE_REQUEST_TIMEOUT | The number of seconds before a purge attempt times out. |
| ACQUIA_PURGE_SEVLEVEL_ERROR | Requirement severity: Error condition, do not purge items in the queue. |
| ACQUIA_PURGE_SEVLEVEL_INFO | Diagnostic severity levels: Informational. |
| ACQUIA_PURGE_SEVLEVEL_OK | Diagnostic severity levels: Good condition. |
| ACQUIA_PURGE_SEVLEVEL_WARNING | Diagnostic severity levels: Warning condition, proceed but flag warning. |