log.py

#!/usr/bin/python

# Trivial logger, to be replaced with something nicer later.

import os, sys, inspect
import repr as reprlib

ERROR=1
WARNING=2
INFO=3
PROGRESS=4
DEBUG=5
DEBUG2=6
DEBUG3=7

logLevelNames = [ "NONE", "ERROR", "WARNING", "INFO", "PROGRESS", "DEBUG", "DEBUG2", "DEBUG3" ]

# Runtime configuration
logLevel = WARNING
fileLogLevel = PROGRESS

ignoreModules = set()   # Ignore these modules
onlyModules = None     # Only show these modules
logFile = None
logFileName = None

lastmsg = None
lastcount = 0

# Number of characters to ignore from filenames
basedirlen = len(inspect.currentframe().f_code.co_filename.rsplit(os.path.sep,1)[0]) + 1


# Custom repr to shorten output

primitives = (int, str, bool, float, list, dict)
has_op = lambda obj, op: callable(getattr(obj, op, None))

class MyRepr(reprlib.Repr):
    def repr(self, obj):
        # Use for classes that don't have a personal repr
        if not isinstance(obj, primitives) and not obj is None:
            if has_op(obj, "__repr__"):
                return obj.__repr__()
            else:
                return "%s(0x%x)" % (obj.__class__.__name__, id(obj))
        else:
            # Hack: repr is old-style class, call method directly
            return reprlib.Repr.repr(self, obj)
 
aRepr = MyRepr()


# From http://stackoverflow.com/questions/2203424/python-how-to-retrieve-class-information-from-a-frame-object
def get_class_name(f):
    try:
        class_name = f.f_locals['self'].__class__.__name__
    except KeyError:
        class_name = None

    return class_name


def logCheck(level):
    return  level <= logLevel or level <= fileLogLevel  
     
    
def log(level, msg = None):
    if level <= logLevel or level <= fileLogLevel:
    
        global lastmsg, lastcount, ignoreModules, onlyModules
        
        cf = inspect.currentframe().f_back
        co = cf.f_code
        
        mod = co.co_filename[basedirlen:]
        modn = mod[:-3]
        
        if onlyModules and modn not in onlyModules:
            return
        
        if modn in ignoreModules:
            return
        
        if mod == "":
            mod = "<Top>"
        
        args = ""
        self = ""
        vn = co.co_varnames
        for i in xrange(0, co.co_argcount):
            n = vn[i]
            if i == 0 and n == "self":
                self = aRepr.repr(cf.f_locals["self"])
                continue
            v = aRepr.repr(cf.f_locals[vn[i]])
            
            args += "%s=%s " % (vn[i], v)
        args = args[:-1]
        
        caller = "%s:%d %s::%s(%s)" % (mod, cf.f_lineno, self, co.co_name, args)
        
        if msg == None:
            msg = " called\n"
        
        fullmsg = u"%s (%s): %s" % (logLevelNames[level], caller, msg)
        
        if fullmsg == lastmsg:
            lastcount += 1
            return
        elif lastcount > 1:
            lastmsg = fullmsg
            lastcount = 1
            fullmsg = "  *** last message repeated %d times\n" % lastcount
            
        
        if level <= logLevel:
            sys.stderr.write(fullmsg)
            sys.stderr.flush()
        
        if logFile != None and level <= fileLogLevel:
            logFile.write(fullmsg)
            logFile.flush()


def setLogLevel(level):
    global logLevel
    
    logLevel = level


def setFileLog(filename, level):
    global fileLogLevel, logFile
    
    log(WARNING)
    
    try:
        logFile = open(filename, "w")
    except Exception,e:
        log(ERROR, "Caught %s trying to open %s as log file!\n" % (e, filename))
        return
    
    logFileName = filename
    
    fileLogLevel = level


def addOnlyModule(mod):
    global onlyModules
    if not onlyModules:
        onlyModules = set()
    
    onlyModules.add(mod)


def subOnlyModule(mod):
    global onlyModules
    if not onlyModules:
        return
    
    onlyModules.discard(mod)
    
    if not len(onlyModules):
        onlyModules = None


def addIgnoreModule(mod):
    global ignoreModules
    if not ignoreModules:
        ignoreModules = set()
    
    ignoreModules.add(mod)


def subIgnoreModule(mod):
    global ignoreModules
    if not ignoreModules:
        return
    
    ignoreModules.discard(mod)
    
    if not len(ignoreModules):
        ignoreModules = None