class LruRepl(cmd.Cmd):
"""LruRepl: The LruCache shell (Read Eval Print loop)
"""
intro = "Welcome to LruCache shell.\n\nType help or ? to list commands.\nCtrl-d or exit to exit.\n"
prompt = "lrucache> "
cache = None
def precmd(self, line):
"""accept command as upper or lower case"""
line = line.lower()
return line
def default(self, line):
"""overrides the default error message."""
print 'ERROR'
return False
def command_preproc(self, line, expected_len):
if self.cache == None:
print "Cache not initialized. Use SIZE command first."
return None
args = line.split()
if len(args) != expected_len:
print "Syntax Error. Expected %d arguments, got %d" % (
expected_len, len(args))
return None
return args
def do_size(self, line):
"""size n - sets the maximum size of the cache to n objects"""
if self.cache == None:
args = line.split()
if len(args) != 1:
print "Syntax Error. Expected 1 arguments, got %d" % len(args)
return False
self.cache = LruCache(int(args[0]))
print("SIZE OK")
else:
print("ERROR")
def do_set(self, line):
"""set key value - puts the key/value pair into the cache if the key does not exist
or overwrites the value of an existing pair
"""
args = self.command_preproc(line, 2)
if args != None:
self.cache.put(args[0], args[1])
print("SET OK")
def do_get(self, line):
"""get key -- prints the value associated the the key if found"""
args = self.command_preproc(line, 1)
if args != None:
v = self.cache.fetch(args[0])
if v == None:
print("NOTFOUND")
else:
print("GOT %s" % v)
def do_stats(self, line):
"""stats - print the cache stats"""
if self.cache == None:
print "Cache not initialized. Use SIZE command first."
return False
print("Cache max size: %d" % self.cache.max_size)
print("Current size: %d" % self.cache.current_size)
def do_dump(self, line):
"""dump - dump the cache"""
if self.cache == None:
print "Cache not initialized. Use SIZE command first."
return False
self.cache.data.dump()
def do_eof(self, line):
"""Ctrl-D to exit"""
print '\n'
return True
def do_exit(self, line):
"""exits shell"""
print "\n"
return True
