batcave.py: split inline code into functions

The new main() method may be called by external callers.

batcave.py

@@ -17,114 +17,138 @@ from ffstatus import \
     Storage
 from ffstatus.exceptions import SanityCheckError
 
+BATCAVE = 'Batman/Alfred Transmission Collection, Aggregation & Value Engine'
 DEFAULT_INTERVAL = 15
 
-parser = argparse.ArgumentParser(description='Batman/Alfred Transmission Collection, Aggregation & Value Engine')
-parser.add_argument('--logfile', help='path for log file')
-parser.add_argument('--interval', type=int, default=DEFAULT_INTERVAL, help='data poll interval')
-parser.add_argument('-v', '--verbose', action='store_true', help='increase output verbosity')
-parser.add_argument('-d', '--no-detach', action='store_true', help='Don\'t detach (daemonize) ourself')
-parser.add_argument('-n', '--no-send', action='store_true', help='Fetch data but don\'t send it')
-parser.add_argument('-A', '--alfred-json', help='executable path for alfred-json')
-parser.add_argument('-B', '--batadv-vis', help='executable path for batadv-vis')
-parser.add_argument('-G', '--graphite-host', help='Graphite host')
-parser.add_argument('--graphite-port', type=int, default=2003, help='Graphite port')
-parser.add_argument('--dashing-url', help='Dashing URL')
-parser.add_argument('--dashing-token', help='Dashing\'s secret update token')
-parser.add_argument('--api-bind-host', default='', help='API-Server Hostname')
-parser.add_argument('--api-bind-port', type=int, default=8888, help='API-Server Port')
-parser.add_argument('-S', '--storage-dir', default='.', help='Path where to store data')
-args = parser.parse_args()
-
-if args.interval < 5:
-    print('A poll interval lower than 5s is not supported.')
-    sys.exit(1)
-
-shall_daemonize = not args.no_detach
-
-logger = logging.getLogger()
-logger.setLevel(logging.DEBUG if args.verbose else logging.INFO)
-
-if not args.logfile is None:
-    fh = logging.FileHandler(args.logfile)
-    fh.setFormatter(logging.Formatter('%(asctime)s [%(levelname)s] %(message)s', '%Y-%m-%d %H:%M:%S'))
-    logger.addHandler(fh)
-
-if args.no_detach:
-    ch = logging.StreamHandler(sys.stdout)
-    ch.setFormatter(logging.Formatter('%(asctime)s [%(levelname)s] %(message)s', '%Y-%m-%d %H:%M:%S'))
-    logger.addHandler(ch)
-
-logger.info('Starting up')
-
-storage = Storage(args.storage_dir)
-storage.open()
-logger.info('Storage: ' + str(storage))
-
-a = AlfredParser()
-b = BatmanParser()
-d = DashingClient(args.dashing_url, args.dashing_token) if not args.dashing_url is None else None
-g = GraphitePush(args.graphite_host, args.graphite_port) if not args.graphite_host is None else None
-
-if args.no_send:
-    if not g is None: g.dont_send = True
-
-if not args.alfred_json is None: a.alfred_json = args.alfred_json
-if not args.batadv_vis is None: b.batadv_vis = args.batadv_vis
-
-logger.debug('Configured A.L.F.R.E.D. source: ' + str(a))
-logger.debug('Configured B.A.T.M.A.N. source: ' + str(b))
-logger.debug('Configured Dashing: ' + str(d))
-logger.debug('Configured Graphite: ' + str(g))
-
-# execute sanitycheck() where possible
-for i in [('AlfredParser', a), ('BatmanParser', b)]:
-    try:
-        i[1].sanitycheck()
-    except SanityCheckError as err:
-        logger.critical(i[0] + '.sanitycheck() failed: ' + str(err))
-        print('FAILED SANITY CHECK: ' + str(err))
-        sys.exit(1)
-
-server = ApiServer((args.api_bind_host, args.api_bind_port), storage)
-server_thread = threading.Thread(target=server.serve_forever)
-server_thread.daemon = True # exit thread when main thread terminates
-server_thread.start()
-logger.info('Started server: ' + str(server))
-
-if shall_daemonize:
-    daemon_context = daemon.DaemonContext(
-        files_preserve=[fh.stream],
-    )
-
-    daemon_context.open()
-
-while True:
-    try:
-        ts = int(time.time())
-        logger.debug('Step 1/3: Fetching data ...')
-        alfreddata = a.fetch()
-        batmandata = b.fetch()
-        newdata = merge_alfred_batman(alfreddata, batmandata)
-        logger.debug('Fetched data: {0} ALFRED with {1} BATMAN makes {2} total'.format(len(alfreddata), len(batmandata), len(newdata)))
 
-        logger.debug('Step 2/3: Pushing update data ...')
-        if not g is None:
-            graphitedata = g.push(newdata, ts=ts)
-            logger.info('Sent ' + str(graphitedata.count('\n')+1) + ' lines to Graphite.')
-        if not d is None:
-            d.push(newdata)
-
-        logger.debug('Step 3/3: Merging current data ...')
-        storage.merge_new_data(newdata)
-
-        logger.debug('I have data for %d nodes.', len(storage.data))
-
-    except Exception as err:
-        logger.error(str(err))
-
-    logger.debug('Sleeping for {0} seconds'.format(args.interval))
-    time.sleep(args.interval)
+def get_args():
+    parser = argparse.ArgumentParser(description=BATCAVE)
+    parser.add_argument('--logfile',
+                        help='path for log file')
+    parser.add_argument('--interval', type=int, default=DEFAULT_INTERVAL,
+                        help='data poll interval')
+    parser.add_argument('-v', '--verbose', action='store_true',
+                        help='increase output verbosity')
+    parser.add_argument('-d', '--no-detach', action='store_true',
+                        help='Don\'t detach (daemonize) ourself')
+    parser.add_argument('-n', '--no-send', action='store_true',
+                        help='Fetch data but don\'t send it')
+    parser.add_argument('-A', '--alfred-json',
+                        help='executable path for alfred-json')
+    parser.add_argument('-B', '--batadv-vis',
+                        help='executable path for batadv-vis')
+    parser.add_argument('-G', '--graphite-host',
+                        help='Graphite host')
+    parser.add_argument('--graphite-port', type=int, default=2003,
+                        help='Graphite port')
+    parser.add_argument('--dashing-url',
+                        help='Dashing URL')
+    parser.add_argument('--dashing-token',
+                        help='Dashing\'s secret update token')
+    parser.add_argument('--api-bind-host', default='',
+                        help='API-Server Hostname')
+    parser.add_argument('--api-bind-port', type=int, default=8888,
+                        help='API-Server Port')
+    parser.add_argument('-S', '--storage-dir', default='.',
+                        help='Path where to store data')
+    return parser.parse_args()
+
+
+def main():
+    args = get_args()
+
+    if args.interval < 5:
+        print('A poll interval lower than 5s is not supported.')
+        sys.exit(1)
 
-storage.close()
-logger.info('Shut down.')
+    shall_daemonize = not args.no_detach
+
+    logger = logging.getLogger()
+    logger.setLevel(logging.DEBUG if args.verbose else logging.INFO)
+
+    if not args.logfile is None:
+        fh = logging.FileHandler(args.logfile)
+        fh.setFormatter(logging.Formatter('%(asctime)s [%(levelname)s] %(message)s', '%Y-%m-%d %H:%M:%S'))
+        logger.addHandler(fh)
+
+    if args.no_detach:
+        ch = logging.StreamHandler(sys.stdout)
+        ch.setFormatter(logging.Formatter('%(asctime)s [%(levelname)s] %(message)s', '%Y-%m-%d %H:%M:%S'))
+        logger.addHandler(ch)
+
+    logger.info('Starting up')
+
+    storage = Storage(args.storage_dir)
+    storage.open()
+    logger.info('Storage: ' + str(storage))
+
+    a = AlfredParser()
+    b = BatmanParser()
+    d = DashingClient(args.dashing_url, args.dashing_token) if not args.dashing_url is None else None
+    g = GraphitePush(args.graphite_host, args.graphite_port) if not args.graphite_host is None else None
+
+    if args.no_send:
+        if not g is None: g.dont_send = True
+
+    if not args.alfred_json is None: a.alfred_json = args.alfred_json
+    if not args.batadv_vis is None: b.batadv_vis = args.batadv_vis
+
+    logger.debug('Configured A.L.F.R.E.D. source: ' + str(a))
+    logger.debug('Configured B.A.T.M.A.N. source: ' + str(b))
+    logger.debug('Configured Dashing: ' + str(d))
+    logger.debug('Configured Graphite: ' + str(g))
+
+    # execute sanitycheck() where possible
+    for i in [('AlfredParser', a), ('BatmanParser', b)]:
+        try:
+            i[1].sanitycheck()
+        except SanityCheckError as err:
+            logger.critical(i[0] + '.sanitycheck() failed: ' + str(err))
+            print('FAILED SANITY CHECK: ' + str(err))
+            sys.exit(1)
+
+    server = ApiServer((args.api_bind_host, args.api_bind_port), storage)
+    server_thread = threading.Thread(target=server.serve_forever)
+    server_thread.daemon = True # exit thread when main thread terminates
+    server_thread.start()
+    logger.info('Started server: ' + str(server))
+
+    if shall_daemonize:
+        daemon_context = daemon.DaemonContext(
+            files_preserve=[fh.stream],
+        )
+
+        daemon_context.open()
+
+    while True:
+        try:
+            ts = int(time.time())
+            logger.debug('Step 1/3: Fetching data ...')
+            alfreddata = a.fetch()
+            batmandata = b.fetch()
+            newdata = merge_alfred_batman(alfreddata, batmandata)
+            logger.debug('Fetched data: {0} ALFRED with {1} BATMAN makes {2} total'.format(len(alfreddata), len(batmandata), len(newdata)))
+
+            logger.debug('Step 2/3: Pushing update data ...')
+            if not g is None:
+                graphitedata = g.push(newdata, ts=ts)
+                logger.info('Sent ' + str(graphitedata.count('\n')+1) + ' lines to Graphite.')
+            if not d is None:
+                d.push(newdata)
+
+            logger.debug('Step 3/3: Merging current data ...')
+            storage.merge_new_data(newdata)
+
+            logger.debug('I have data for %d nodes.', len(storage.data))
+
+        except Exception as err:
+            logger.error(str(err))
+
+        logger.debug('Sleeping for {0} seconds'.format(args.interval))
+        time.sleep(args.interval)
+
+    storage.close()
+    logger.info('Shut down.')
+
+if __name__ == '__main__':
+    main()