more shutdown tweaks

brozzler/browser.py

@@ -77,7 +77,7 @@ class BrowserPool:
             try:
                 browser = self._available.pop()
             except KeyError:
-                raise NoBrowsersAvailable()
+                raise NoBrowsersAvailable
             self._in_use.add(browser)
             return browser
 
@@ -87,8 +87,12 @@ class BrowserPool:
             self._in_use.remove(browser)
 
     def shutdown_now(self):
-        self.logger.info('shutting down browser pool')
+        self.logger.info(
+                'shutting down browser pool (%s browsers in use)',
+                len(self._in_use))
         with self._lock:
+            for browser in self._available:
+                browser.stop()
             for browser in self._in_use:
                 browser.stop()
 
@@ -114,6 +118,7 @@ class Browser:
         self.chrome = Chrome(**kwargs)
         self.websocket_url = None
         self.is_browsing = False
+        self._browser_controller = None
 
     def __enter__(self):
         self.start()
@@ -139,10 +144,10 @@ class Browser:
         Stops chrome if it's running.
         '''
         try:
-            if self.is_running():
+            if self._browser_controller:
                 self._browser_controller.stop()
-                self.websocket_url = None
-                self.chrome.stop()
+            self.websocket_url = None
+            self.chrome.stop()
         except:
             self.logger.error('problem stopping', exc_info=True)
 
@@ -215,19 +220,9 @@ class Browser:
             ##     outlinks += retrieve_outlinks (60 sec)
             final_page_url = self._browser_controller.url()
             return final_page_url, outlinks
-        except brozzler.ShutdownRequested:
-            self.logger.info('shutdown requested')
-            raise
         except websocket.WebSocketConnectionClosedException as e:
-            # import pdb; pdb.set_trace()
+            self.logger.error('websocket closed, did chrome die?')
             raise BrowsingException(e)
-            # if not self.is_running():
-            #     logging.info('appears shutdown was requested')
-            #     return None, None
-            # else:
-            #     raise BrowsingException(
-            #             "websocket closed, did chrome die? %s" % (
-            #                 self.websocket_url))
         finally:
             self.is_browsing = False
 
@@ -287,8 +282,12 @@ class BrowserController:
                 '''
                 Raises BrowsingException in the thread that called start()
                 '''
-                self.logger.error(
-                        'exception from websocket receiver thread', exc_info=1)
+                if isinstance(e, websocket.WebSocketConnectionClosedException):
+                    self.logger.error('websocket closed, did chrome die?')
+                else:
+                    self.logger.error(
+                            'exception from websocket receiver thread',
+                            exc_info=1)
                 brozzler.thread_raise(calling_thread, BrowsingException)
 
             # open websocket, start thread that receives messages

brozzler/chrome.py

@@ -50,6 +50,7 @@ class Chrome:
         self.chrome_exe = chrome_exe
         self.ignore_cert_errors = ignore_cert_errors
         self._shutdown = threading.Event()
+        self.chrome_process = None
 
     def __enter__(self):
         '''
@@ -188,6 +189,8 @@ class Chrome:
                             'got chrome window websocket debug url %s from %s',
                             url, json_url)
                     return url
+            except brozzler.ShutdownRequested:
+                raise
             except BaseException as e:
                 if int(time.time() - self._start) % 10 == 5:
                     self.logger.warn(
@@ -253,18 +256,18 @@ class Chrome:
     def stop(self):
         if not self.chrome_process or self._shutdown.is_set():
             return
+        self._shutdown.set()
 
         timeout_sec = 300
-        self._shutdown.set()
-        self.logger.info('terminating chrome pgid %s' % self.chrome_process.pid)
+        if self.chrome_process.poll() is None:
+            self.logger.info(
+                    'terminating chrome pgid %s', self.chrome_process.pid)
 
-        os.killpg(self.chrome_process.pid, signal.SIGTERM)
-        first_sigterm = time.time()
+            os.killpg(self.chrome_process.pid, signal.SIGTERM)
+        t0 = time.time()
 
         try:
-            while time.time() - first_sigterm < timeout_sec:
-                time.sleep(0.5)
-
+            while time.time() - t0 < timeout_sec:
                 status = self.chrome_process.poll()
                 if status is not None:
                     if status == 0:
@@ -281,11 +284,12 @@ class Chrome:
                     # around, but there's a chance I suppose that some other
                     # process could have started with the same pgid
                     return
+                time.sleep(0.5)
 
             self.logger.warn(
                     'chrome pid %s still alive %.1f seconds after sending '
                     'SIGTERM, sending SIGKILL', self.chrome_process.pid,
-                    time.time() - first_sigterm)
+                    time.time() - t0)
             os.killpg(self.chrome_process.pid, signal.SIGKILL)
             status = self.chrome_process.wait()
             self.logger.warn(
@@ -301,3 +305,4 @@ class Chrome:
         finally:
             self._out_reader_thread.join()
             self.chrome_process = None
+

brozzler/worker.py

@@ -322,9 +322,9 @@ class BrozzlerWorker:
         return False
 
     def _brozzle_site(self, browser, site):
-        start = time.time()
         page = None
         try:
+            start = time.time()
             while time.time() - start < 7 * 60:
                 self._frontier.honor_stop_request(site.job_id)
                 page = self._frontier.claim_page(site, "%s:%s" % (