[Patch pyserial:34] Improvements to port_publisher.py example
diff --git a/examples/port_publisher.py b/examples/port_publisher.py
index 393beb5..d05a631 100755
--- a/examples/port_publisher.py
+++ b/examples/port_publisher.py
@@ -18,10 +18,25 @@
import serial
import serial.rfc2217
+import serial.tools.list_ports
-import avahi
import dbus
+# Try to import the avahi service definitions properly. If the avahi module is
+# not available, fall back to a hard-coded solution that hopefully still works.
+try:
+ import avahi
+except ImportError:
+ class avahi:
+ DBUS_NAME = "org.freedesktop.Avahi"
+ DBUS_PATH_SERVER = "/"
+ DBUS_INTERFACE_SERVER = "org.freedesktop.Avahi.Server"
+ DBUS_INTERFACE_ENTRY_GROUP = DBUS_NAME + ".EntryGroup"
+ IF_UNSPEC = -1
+ PROTO_UNSPEC, PROTO_INET, PROTO_INET6 = -1, 0, 1
+
+
+
class ZeroconfService:
"""\
A simple class to publish a network service with zeroconf using avahi.
@@ -133,7 +148,7 @@
self.handle_server_error()
#~ raise
if not options.quiet:
- print "%s: Waiting for connection on %s..." % (self.device, self.network_port)
+ print("%s: Waiting for connection on %s..." % (self.device, self.network_port))
# zeroconfig
self.publish()
@@ -259,6 +274,14 @@
connection, addr = self.server_socket.accept()
if self.socket is None:
self.socket = connection
+ # More quickly detect bad clients who quit without closing the
+ # connection: After 1 second of idle, start sending TCP keep-alive
+ # packets every 1 second. If 3 consecutive keep-alive packets
+ # fail, assume the client is gone and close the connection.
+ self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1)
+ self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_KEEPIDLE, 1)
+ self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_KEEPINTVL, 1)
+ self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_KEEPCNT, 3)
self.socket.setblocking(0)
self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
if not options.quiet:
@@ -331,6 +354,10 @@
parser.add_option("", "--pidfile", dest="pid_file",
help="specify a name for the PID file", default=None, metavar="FILE")
+ parser.add_option("", "--ports-regex", dest="ports_regex",
+ help="specify a regex to search against the serial devices and their descriptions",
+ default='/dev/ttyUSB[0-9]+', metavar="REGEX")
+
(options, args) = parser.parse_args()
# redirect output if specified
@@ -406,8 +433,6 @@
# keep the published stuff in a dictionary
published = {}
- # prepare list of device names (hard coded)
- device_list = ['/dev/ttyUSB%d' % p for p in range(8)]
# get a nice hostname
hostname = socket.gethostname()
@@ -429,29 +454,26 @@
now = time.time()
if now > next_check:
next_check = now + 5
- # check each device
- for device in device_list:
- # if it appeared
- if os.path.exists(device):
- if device not in published:
- num = int(device[-1])
- published[device] = Forwarder(
- device,
- "%s on %s" % (device, hostname),
- 7000+num,
- on_close=unpublish
- )
- if not options.quiet: print("publish: %s" % (published[device]))
- published[device].open()
- else:
- # or when it disappeared
- if device in published:
- if not options.quiet: print("unpublish: %s" % (published[device]))
- published[device].close()
- try:
- del published[device]
- except KeyError:
- pass
+ connected = [d for d, p, i in serial.tools.list_ports.grep(options.ports_regex)]
+ # Handle devices that are published, but no longer connected
+ for device in set(published).difference(connected):
+ if not options.quiet: print("unpublish: %s" % (published[device]))
+ unpublish(published[device])
+ # Handle devices that are connected but not yet published
+ for device in set(connected).difference(published):
+ # Find the first available port, starting from 7000
+ port = 7000
+ ports_in_use = [f.network_port for f in published.values()]
+ while port in ports_in_use:
+ port += 1
+ published[device] = Forwarder(
+ device,
+ "%s on %s" % (device, hostname),
+ port,
+ on_close=unpublish
+ )
+ if not options.quiet: print("publish: %s" % (published[device]))
+ published[device].open()
# select_start = time.time()
read_map = {}