ZeroNet/src/Worker/Worker.py

import time

import gevent

from Debug import Debug
from Config import config


class Worker(object):

    def __init__(self, manager, peer):
        self.manager = manager
        self.peer = peer
        self.task = None
        self.key = None
        self.running = False
        self.thread = None

    def __str__(self):
        return "Worker %s %s" % (self.manager.site.address_short, self.key)

    def __repr__(self):
        return "<%s>" % self.__str__()

    # Downloader thread
    def downloader(self):
        self.peer.hash_failed = 0  # Reset hash error counter
        while self.running:
            # Try to pickup free file download task
            task = self.manager.getTask(self.peer)
            if not task:  # Die, no more task
                self.manager.log.debug("%s: No task found, stopping" % self.key)
                break
            if not task["time_started"]:
                task["time_started"] = time.time()  # Task started now

            if task["workers_num"] > 0:  # Wait a bit if someone already working on it
                if config.verbose:
                    self.manager.log.debug("%s: Someone already working on %s (pri: %s), sleeping 1 sec..." % (self.key, task["inner_path"], task["priority"]))
                for sleep_i in range(1,10):
                    time.sleep(0.1)
                    if task["done"] or task["workers_num"] == 0:
                        if config.verbose:
                            self.manager.log.debug("%s: %s, picked task free after %ss sleep. (done: %s)" % (self.key, task["inner_path"], 0.1 * sleep_i, task["done"]))
                        break

            if task["done"] is False:
                self.task = task
                site = task["site"]
                task["workers_num"] += 1
                try:
                    buff = self.peer.getFile(site.address, task["inner_path"], task["size"])
                except Exception, err:
                    self.manager.log.debug("%s: getFile error: %s" % (self.key, err))
                    buff = None
                if self.running is False:  # Worker no longer needed or got killed
                    self.manager.log.debug("%s: No longer needed, returning: %s" % (self.key, task["inner_path"]))
                    break
                if task["done"] is True:  # Task done, try to find new one
                    continue
                if buff:  # Download ok
                    try:
                        correct = site.content_manager.verifyFile(task["inner_path"], buff)
                    except Exception, err:
                        correct = False
                else:  # Download error
                    err = "Download failed"
                    correct = False
                if correct is True or correct is None:  # Verify ok or same file
                    self.manager.log.debug("%s: Verify correct: %s" % (self.key, task["inner_path"]))
                    if correct is True and task["done"] is False:  # Save if changed and task not done yet
                        buff.seek(0)
                        site.storage.write(task["inner_path"], buff)
                    if task["done"] is False:
                        self.manager.doneTask(task)
                    task["workers_num"] -= 1
                    self.task = None
                else:  # Verify failed
                    self.manager.log.debug(
                        "%s: Verify failed: %s, error: %s, failed peers: %s" %
                        (self.key, task["inner_path"], err, len(task["failed"]))
                    )
                    task["failed"].append(self.peer)
                    self.task = None
                    self.peer.hash_failed += 1
                    if self.peer.hash_failed >= max(len(self.manager.tasks), 3) or self.peer.connection_error > 10:
                        # Broken peer: More fails than tasks number but atleast 3
                        break
                    task["workers_num"] -= 1
                    time.sleep(1)
        self.peer.onWorkerDone()
        self.running = False
        self.manager.removeWorker(self)

    # Start the worker
    def start(self):
        self.running = True
        self.thread = gevent.spawn(self.downloader)

    # Skip current task
    def skip(self):
        self.manager.log.debug("%s: Force skipping" % self.key)
        if self.thread:
            self.thread.kill(exception=Debug.Notify("Worker stopped"))
        self.start()

    # Force stop the worker
    def stop(self):
        self.manager.log.debug("%s: Force stopping" % self.key)
        self.running = False
        if self.thread:
            self.thread.kill(exception=Debug.Notify("Worker stopped"))
        del self.thread
        self.manager.removeWorker(self)