/**
* This is called after setup() returns
* @return void
*/
public function start()
{
// This is just going to sleep a really long time.
// I'll replace this with a better demo in a future version.
// The idea is that the easiest way to parallelize some code in your daemon is to pass a closure or callback to the task() method.
// But if you have a complex task that can get ugly and difficult to read and understand. In those cases, you can implement
// a Core_ITask object like this one.
$this->daemon->log("Starting BigTask...");
sleep($this->sleep_duration);
if ($this->wakeup_message) {
$this->daemon->log($this->wakeup_message);
}
}
/**
* Maintain the worker process map and notify the worker of an exited process.
* @param bool $block When true, method will block waiting for an exit signal
* @return void
*/
public function reap($block = false)
{
$map = $this->processes();
while (true) {
$pid = pcntl_wait($status, $block === true && $this->daemon->is('parent') ? NULL : WNOHANG);
if (!$pid || !isset($map[$pid])) {
break;
}
$alias = $map[$pid]->group;
$process = $this->processes[$alias][$pid];
$this->daemon->dispatch(array(Core_Daemon::ON_REAP), array($process, $status));
unset($this->processes[$alias][$pid]);
// Keep track of process churn -- failures within a processes min_ttl
// If too many failures of new processes occur inside a given interval, that's a problem.
// Raise a fatal error to prevent runaway process forking which can be very damaging to a server
if ($this->daemon->is('shutdown') || $process->runtime() >= $process->min_ttl) {
continue;
}
foreach ($this->failures as $key => $failure_time) {
if ($failure_time + self::CHURN_WINDOW < time()) {
unset($this->failures[$key]);
}
}
if (count($this->failures) > self::CHURN_LIMIT) {
$this->daemon->fatal_error("Recently forked processes are continuously failing. See error log for additional details.");
}
}
}
/**
* Start the engines own loop
*
* @return void
*/
public function doWork()
{
$this->mediator->log('Sunrise is working');
while (!\Core_Daemon::is('shutdown')) {
usleep(1000);
}
}
/**
* serializes the build before shutting down
*
* @return void
*/
public function tearDown()
{
if (!\Core_Daemon::is('parent')) {
$this->mediator->log('TearDown');
if ($this->build != null) {
$this->serializeBuild($this->build);
$this->build = null;
}
}
}
/**
* This is called after setup() returns
* @return void
*/
public function start()
{
$post = $this->post;
// Send to Twitter:
$tmhOAuth = new \tmhOAuth(array());
$code = $tmhOAuth->request('POST', $tmhOAuth->url('1/statuses/update'), array('status' => $post['content']));
// There is no special handling of API errors.
// Right now we just dump the response to MongoDB
$post['code'] = $code;
$post['response'] = json_decode($tmhOAuth->response['response'], true);
// Move this post to another collection named archive:
unset($post['processing']);
unset($post['processing_time']);
$m = new \Mongo();
$m->tampon->archive->insert($post);
$m->tampon->posts->remove(array('_id' => $post['_id']));
if ($code == 200) {
$this->daemon->log(sprintf("Sent post %s to Twitter, Twitter id: %s by user %s", $post['_id'], (string) $post['response']['id'], $post['response']['screen_name']));
} else {
$this->daemon->log(sprintf("Failed sending post %s to Twitter, error code %s: %s", $post['_id'], (string) $code, $post['response']['error']), "warning");
}
}
/**
* Dispatch ON_ERROR event, write an error message to the event log, and restart the worker.
*
* Part of the Worker API - Use from your worker to log a fatal error message and restart the current process.
*
* @param $message
* @return void
*/
public function fatal_error($message)
{
if ($this->daemon->is('parent')) {
$this->daemon->fatal_error("Fatal Error: {$message}", $this->alias);
} else {
$this->daemon->fatal_error("Fatal Error: {$message}\nWorker process will restart", $this->alias);
}
}
private function log($message)
{
$this->daemon->log($message, 'SocketServer');
}
/**
* Log the $message to the filename returned by Core_Daemon::log_file() and/or optionally print to stdout.
* Multi-Line messages will be handled nicely.
*
* Note: Your log_file() method will be called every 5 minutes (at even increments, eg 00:05, 00:10, 00:15, etc) to
* allow you to rotate the filename based on time (one log file per month, day, hour, whatever) if you wish.
*
* Note: You may find value in overloading this method in your app in favor of a more fully-featured logging tool
* like log4php or Zend_Log. There are fantastic logging libraries available, and this simplistic home-grown option
* was chosen specifically to avoid forcing another dependency on you.
*
* @param string $message
* @param string $label Truncated at 12 chars
*/
public function log($message, $label = '', $indent = 0)
{
static $log_file = '';
static $log_file_check_at = 0;
static $log_file_error = false;
$header = "\nDate PID Label Message\n";
$date = date("Y-m-d H:i:s");
$pid = str_pad($this->pid, 5, " ", STR_PAD_LEFT);
$label = str_pad(substr($label, 0, 12), 13, " ", STR_PAD_RIGHT);
$prefix = "[{$date}] {$pid} {$label}" . str_repeat("\t", $indent);
if (time() >= $log_file_check_at && $this->log_file() != $log_file) {
$log_file = $this->log_file();
$log_file_check_at = mktime(date('H'), date('i') - date('i') % 5 + 5, null);
@fclose(self::$log_handle);
self::$log_handle = $log_file_error = false;
}
if (self::$log_handle === false) {
if (strlen($log_file) > 0 && (self::$log_handle = @fopen($log_file, 'a+'))) {
if ($this->is('parent')) {
fwrite(self::$log_handle, $header);
if ($this->is('stdout')) {
echo $header;
}
}
} elseif (!$log_file_error) {
$log_file_error = true;
trigger_error(__CLASS__ . "Error: Could not write to logfile " . $log_file, E_USER_WARNING);
}
}
$message = $prefix . ' ' . str_replace("\n", "\n{$prefix} ", trim($message)) . "\n";
if (self::$log_handle) {
fwrite(self::$log_handle, $message);
}
if ($this->is('stdout')) {
echo $message;
}
}
/**
* Display a command prompt, block on input from STDIN, then parse and execute the specified commands.
*
* Multiple processes share a single command prompt by accessing a semaphore identified by the current application.
* This method will block the process while it waits for the mutex, and then again while it waits for input on STDIN.
*
* The text of the prompt itself will be written when get_text_prompt() is called. Custom prompts for a given $method
* can be added to the $prompts array.
*
* Several commands are built-in, and additional commands can be added with addParser().
*
* Parsers can either:
* 1. Continue from the prompt.
* 2. Abort from the prompt. Call any interrupt_callable that may be registered for this $method.
* 3. Take some action or perform some activity and then return to the same prompt for additional commands.
*
* @param $method
* @param $args
* @return bool|int|mixed|null
* @throws Exception
*/
public function prompt($method, $args)
{
if (!is_resource($this->shm)) {
return true;
}
// The single debug shell is shared across the parent and all worker processes. Use a mutex to serialize
// access to the shell. If the mutex isn't owned by this process, this will block until this process acquires it.
$this->mutex_acquire();
if (!$this->is_breakpoint_active($method)) {
$this->mutex_release();
return true;
}
// Pass a simple print-line closure to parsers to use instead of just "echo" or "print"
$printer = function ($message, $maxlen = null) {
if (empty($message)) {
return;
}
if ($maxlen && strlen($message) > $maxlen) {
$message = substr($message, 0, $maxlen - 3) . '...';
}
$message = str_replace(PHP_EOL, PHP_EOL . ' ', $message);
echo " {$message}\n\n";
};
try {
$this->print_banner();
$pid = getmypid();
$prompt = $this->get_text_prompt($method, $args);
$break = false;
// We have to clear the buffer of any input that occurred in the terminal in the space after they submitted their last
// command and before this new prompt. Otherwise it'll be read from fgets below and probably ruin everything.
stream_set_blocking(STDIN, 0);
while (fgets(STDIN)) {
continue;
}
stream_set_blocking(STDIN, 1);
// Commands that set $break=true will continue forward from the command prompt.
// Otherwise it will just do the action (or display an error) and then repeat the prompt
while (!$break) {
echo $prompt;
$input = trim(fgets(STDIN));
$input = preg_replace('/\\s+/', ' ', $input);
$matches = false;
$message = '';
// Use the familiar bash !! to re-run the last command
if (substr($input, -2) == '!!') {
$input = $this->debug_state('last');
} elseif (!empty($input)) {
$this->debug_state('last', $input);
}
// Validate the input as an expression
$matches = array();
foreach ($this->parsers as $parser) {
if (preg_match($parser['regex'], $input, $matches) == 1) {
$break = $parser['closure']($matches, $printer);
break;
}
}
if ($matches) {
continue;
}
// If one of the parsers didn't catch the message
// fall through to the built-in commands
switch (strtolower($input)) {
case 'help':
$out = array();
$out[] = 'For the PHP Simple Daemon debugging guide, see: ';
$out[] = 'https://github.com/shaneharter/PHP-Daemon/wiki/Debugging-Workers';
$out[] = '';
$out[] = 'Available Commands:';
$out[] = 'y Step to the next break point';
$out[] = 'n Interrupt';
$out[] = '';
$out[] = 'capture Call the current method and capture its return value. Will print_r the return value and return a prompt.';
$out[] = 'end End the debugging session, continue the daemon as normal.';
$out[] = 'help Print This Help';
$out[] = 'kill Kill the daemon and all of its worker processes.';
$out[] = 'skip Skip this breakpoint from now on.';
$out[] = 'shutdown End Debugging and Gracefully shutdown the daemon after the current loop_interval.';
$out[] = 'trace Print A Stack Trace';
if (is_callable($this->indent_callback)) {
$out[] = 'indent [y|n] When turned-on, indentation will be used to group messages from the same call in a column so you can easily match them together.';
}
$out[] = '';
foreach ($this->parsers as $parser) {
$out[] = sprintf('%s%s', str_pad($parser['command'], 18, ' ', STR_PAD_RIGHT), $parser['description']);
}
$out[] = '';
$out[] = '!! Repeat previous command';
$printer(implode(PHP_EOL, $out));
break;
case 'indent y':
$this->debug_state('indent', true);
$printer('Indent enabled');
break;
case 'indent n':
$this->debug_state('indent', false);
$printer('Indent disabled');
break;
case 'show args':
$printer(print_r($args, true));
break;
case 'shutdown':
//$this->daemon->shutdown();
$printer("Shutdown In Progress... Use `end` command to cease debugging until shutdown is complete.");
$break = true;
break;
case 'trace':
$e = new exception();
$printer($e->getTraceAsString());
break;
case 'end':
$this->debug_state('enabled', false);
$break = true;
$printer('Debugging Ended..');
$input = true;
break;
case 'skip':
$this->debug_state("skip_{$method}", true);
$printer('Breakpoint "' . $method . '" Turned Off..');
$break = true;
$input = true;
break;
case 'kill':
@fclose(STDOUT);
@fclose(STDERR);
@exec('ps -C "php ' . Core_Daemon::get('filename') . '" -o pid= | xargs kill -9 ');
break;
case 'capture':
$backtrace = debug_backtrace();
if ($backtrace[1]['function'] !== '__call' || $method == self::CAPTURE) {
$printer('Cannot capture this :(');
break;
}
$input = self::CAPTURE;
$break = true;
break;
case 'y':
$input = self::CONT;
$break = true;
break;
case 'n':
$input = self::ABORT;
$break = true;
break;
default:
if ($input) {
$printer("Unknown Command! See `help` for list of commands.");
}
}
}
} catch (Exception $e) {
$this->mutex_release();
throw $e;
}
$this->mutex_release();
return $input;
}
public function setup()
{
$ftok = ftok(Core_Daemon::get('filename'), 'L');
$this->shm = shm_attach($ftok, 512, 0666);
}
/**
* Handle IPC Errors
* @param $error
* @param int $try Inform error() of repeated failures of the same $error_code
* @return boolean Returns true if the operation should be retried.
*/
public function error($error, $try = 1)
{
// Create an array of random, moderate size and verify it can be written to shared memory
// Return boolean
$that = $this;
$test = function () use($that) {
$arr = array_fill(0, mt_rand(10, 100), mt_rand(1000, 1000 * 1000));
$key = mt_rand(1000 * 1000, 2000 * 1000);
@shm_put_var($that->shm, $key, $arr);
usleep(5000);
return @shm_get_var($that->shm, $key) == $arr;
};
switch ($error) {
case 0:
// Success
// Success
case 4:
// System Interrupt
// System Interrupt
case MSG_ENOMSG:
// No message of desired type
// Ignored Errors
return true;
break;
case MSG_EAGAIN:
// Temporary Problem, Try Again
usleep($this->mediator->backoff(20000, $try));
return true;
break;
case 13:
// Permission Denied
$this->mediator->count_error('communication');
$this->mediator->log('Permission Denied: Cannot connect to message queue');
$this->purge_mq();
if (Core_Daemon::is('parent')) {
usleep($this->mediator->backoff(100000, $try));
} else {
sleep($this->mediator->backoff(3, $try));
}
$this->setup_ipc();
return true;
break;
case 22:
// Invalid Argument
// Probably because the queue was removed in another process.
// Invalid Argument
// Probably because the queue was removed in another process.
case 43:
// Identifier Removed
// A message queue was re-created at this address but the resource identifier we have needs to be re-created
$this->mediator->count_error('communication');
if (Core_Daemon::is('parent')) {
usleep($this->mediator->backoff(20000, $try));
} else {
sleep($this->mediator->backoff(2, $try));
}
$this->setup_ipc();
return true;
break;
case self::ERROR_UNKNOWN:
// Almost certainly an issue with shared memory
$this->mediator->log("Shared Memory I/O Error at Address {$this->mediator->guid}.");
$this->mediator->count_error('corruption');
// If this is a worker, all we can do is try to re-attach the shared memory.
// Any corruption or OOM errors will be handled by the parent exclusively.
if (!Core_Daemon::is('parent')) {
sleep($this->mediator->backoff(3, $try));
$this->setup_ipc();
return true;
}
// If this is the parent, do some diagnostic checks and attempt correction.
usleep($this->mediator->backoff(20000, $try));
// Test writing to shared memory using an array that should come to a few kilobytes.
for ($i = 0; $i < 2; $i++) {
if ($test()) {
return true;
}
// Re-attach the shared memory and try the diagnostic again
$this->setup_ipc();
}
$this->mediator->log("IPC DIAG: Re-Connect failed to solve the problem.");
if (!$this->mediator->daemon->is('parent')) {
break;
}
// Attempt to re-connect the shared memory
// See if we can read what's in shared memory and re-write it later
$items_to_copy = array();
$items_to_call = array();
for ($i = 0; $i < $this->mediator->call_count; $i++) {
$call = @shm_get_var($this->shm, $i);
if (!is_object($call)) {
continue;
}
$cached = $this->mediator->get_struct($i);
if (!is_object($cached)) {
continue;
}
if ($cached->status == Core_Worker_Mediator::TIMEOUT) {
continue;
}
if ($cached->status == Core_Worker_Mediator::UNCALLED) {
$items_to_call[$i] = $call;
continue;
}
$items_to_copy[$i] = $call;
}
$this->mediator->log("IPC DIAG: Preparing to clean SHM and Reconnect...");
for ($i = 0; $i < 2; $i++) {
$this->purge_shm();
$this->setup_ipc();
if (!empty($items_to_copy)) {
foreach ($items_to_copy as $key => $value) {
@shm_put_var($this->shm, $key, $value);
}
}
if (!$test()) {
if (empty($items_to_copy)) {
$this->mediator->fatal_error("Shared Memory Failure: Unable to proceed.");
} else {
$this->mediator->log('IPC DIAG: Purging items from shared memory: ' . implode(', ', array_keys($items_to_copy)));
unset($items_to_copy);
}
}
}
foreach ($items_to_call as $call) {
$this->mediator->retry($call);
}
return true;
default:
if ($error) {
$this->mediator->log("Message Queue Error {$error}: " . posix_strerror($error));
}
if (Core_Daemon::is('parent')) {
usleep($this->mediator->backoff(100000, $try));
} else {
sleep($this->mediator->backoff(3, $try));
}
$this->mediator->count_error('catchall');
$this->setup_ipc();
return false;
}
}
