more cleanups, started on nice logging framework

diff --git a/sql-edition/servers/VendServer.py b/sql-edition/servers/VendServer.py
index 9ee8ef1..9e1ba7a 100755 (executable)
--- a/sql-edition/servers/VendServer.py
+++ b/sql-edition/servers/VendServer.py
@@ -6,7 +6,7 @@ USE_DB = 0
 import ConfigParser
 import sys, os, string, re, pwd, signal
 import logging
-from traceback import print_tb
+from traceback import format_tb
 if USE_DB: import pg
 from time import time, sleep
 from popen2 import popen2
@@ -389,12 +389,14 @@ def parse_args():
 
        op = OptionParser(usage="%prog [OPTION]...")
        op.add_option('-f', '--config-file', default='/etc/dispense/servers.conf', metavar='FILE', dest='config_file', help='use the specified config file instead of /etc/dispense/servers.conf')
-       op.add_option('-v', '--virtualvend', action='store_false', default=True, dest='use_lat', help='use the virtual vending server instead of LAT')
+       op.add_option('--virtualvend', action='store_false', default=True, dest='use_lat', help='use the virtual vending server instead of LAT')
        op.add_option('-n', '--hostname', dest='host', default='localhost', help='the hostname to connect to for virtual vending machine mode (default: localhost)')
        op.add_option('-p', '--port', dest='port', default=5150, type='int', help='the port number to connect to (default: 5150)')
        op.add_option('-l', '--log-file', metavar='FILE', dest='log_file', default='', help='log output to the specified file')
        op.add_option('-s', '--syslog', dest='syslog', action='store_true', default=False, help='log output to syslog')
        op.add_option('-d', '--daemon', dest='daemon', action='store_true', default=False, help='run as a daemon')
+       op.add_option('-v', '--verbose', dest='verbose', action='store_true', default=False, help='spit out lots of debug output')
+       op.add_option('--pid-file', dest='pid_file', metavar='FILE', default='', help='store daemon\'s pid in the given file')
        options, args = op.parse_args()
 
        if len(args) != 0:
@@ -431,7 +433,15 @@ class VendConfigFile:
                        print "Error reading config file "+config_file+": " + str(e)
                        sys.exit(1)
 
-def set_stuff_up()
+def create_pid_file(name):
+       try:
+               pid_file = file(name, 'w')
+               pid_file.write('%d\n'%os.getpid())
+               pid_file.close()
+       except IOError, e:
+               logging.warning('unable to write to pid file '+name+': '+str(e))
+
+def set_stuff_up():
        def do_nothing(signum, stack): pass
        def stop_server(signum, stack): raise KeyboardInterrupt
        signal.signal(signal.SIGHUP, do_nothing)
@@ -442,10 +452,39 @@ def set_stuff_up()
        config_opts = VendConfigFile(options.config_file, config_options)
        set_up_logging(options)
        if options.daemon: become_daemon()
+       if options.pid_file != '': create_pid_file(options.pid_file)
 
        return options, config_opts
 
-def become_daemon(options):
+def clean_up_nicely(options, config_opts):
+       if options.pid_file != '':
+               try:
+                       os.unlink(options.pid_file)
+                       logging.debug('Removed pid file '+options.pid_file)
+               except OSError: pass  # if we can't delete it, meh
+
+def set_up_logging(options):
+       logger = logging.getLogger()
+       
+       stderr_logger = logging.StreamHandler(sys.stderr)
+       stderr_logger.setFormatter(logging.Formatter('%(levelname)s: %(message)s'))
+       logger.addHandler(stderr_logger)
+       
+       if options.log_file != '':
+               try:
+                       file_logger = logging.FileHandler(options.log_file)
+                       file_logger.setFormatter(logging.Formatter('%(asctime)s %(levelname)s: %(message)s'))
+                       logger.addHandler(file_logger)
+               except IOError, e:
+                       logger.warning('unable to write to log file '+options.log_file+': '+str(e))
+       
+       if options.verbose:
+               logger.setLevel(logging.DEBUG)
+       else:
+               logger.setLevel(logging.INFO)
+       
+
+def become_daemon():
        dev_null = file('/dev/null')
        fd = dev_null.fileno()
        os.dup2(fd, 0)
@@ -476,24 +515,27 @@ if __name__ == '__main__':
        options, config_opts = set_stuff_up()
        while True:
                try:
+                       logging.info('Starting Vend Server')
                        do_vend_server(options, config_opts)
+                       logging.warning('Vend Server finished unexpectedly, restarting')
                except KeyboardInterrupt:
-                       print "Killed by signal."
+                       logging.info("Killed by signal, cleaning up")
+                       clean_up_nicely(options, config_opts)
+                       logging.info("Vend Server stopped")
                        break
-               except SystemExit, e:
-                       raise e
                except:
                        (exc_type, exc_value, exc_traceback) = sys.exc_info()
-                       print
-                       print "Uh-oh, unhandled " + str(exc_type) + " exception"
-                       print "Message: ", str(exc_value)
-                       print
-                       print_tb(exc_traceback)
+                       tb = format_tb(exc_traceback, 20)
                        del exc_traceback
-                       print
-                       print "This message should be considered a bug in the Vend Server."
-                       print "Please report this to someone who can fix it."
+                       
+                       logging.critical("Uh-oh, unhandled " + str(exc_type) + " exception")
+                       logging.critical("Message: " + str(exc_value))
+                       logging.critical("Traceback:")
+                       for event in tb:
+                               for line in event.split('\n'):
+                                       logging.critical('    '+line)
+                       logging.critical("This message should be considered a bug in the Vend Server.")
+                       logging.critical("Please report this to someone who can fix it.")
                        sleep(10)
-                       print
-                       print "Trying again anyway (might not help, but hey...)"
+                       logging.warning("Trying again anyway (might not help, but hey...)")