Initial development

applog.py

@@ -0,0 +1,126 @@
+#!/usr/bin/env python3
+
+#
+#############################################################################
+#
+# applog - Application logging
+# Copyright (C) 2020, Horshack
+#
+# This module is licensed under GPL v3: http://www.gnu.org/licenses/gpl-3.0.html
+#
+#############################################################################
+#
+
+from strutil import *
+import sys
+
+#
+# logging flags
+#
+
+# logging level flags
+APPLOGF_LEVEL_ERROR             = (0x00000001<<0)
+APPLOGF_LEVEL_INFORMATIONAL     = (0x00000001<<1)
+APPLOGF_LEVEL_WARNING           = (0x00000001<<2)
+APPLOGF_LEVEL_VERBOSE           = (0x00000001<<3)
+APPLOGF_LEVEL_DEBUG             = (0x00000001<<4)
+APPLOGF_LEVEL_MASK              = 0x000000FF
+APPLOGF_DONT_WRITE_TO_CONSOLE   = (0x00000001<<8)
+
+#
+# global variables
+# 
+gFileSessionLog = None
+gFileLifetimeLog = None
+gLoggingFlags = 0
+
+#
+# initialize this module, which includes opening log file(s) for writing
+#
+def applog_init(loggingFlags=APPLOGF_LEVEL_INFORMATIONAL | APPLOGF_LEVEL_ERROR, sessionLogFilename=None, lifetimeLogFilename=None):
+    global gFileSessionLog, gFileLifetimeLog, gLoggingFlags
+    gLoggingFlags = loggingFlags
+    if sessionLogFilename:
+        try:
+                gFileSessionLog = open(sessionLogFilename, "w")
+        except IOError as e:
+            print("Unable to open/create logfile \"{:s}\". {:s}".format(sessionLogFilename, str(e)))
+            return e.errno
+    if lifetimeLogFilename:
+        try:
+                gFileLifetimeLog = open(lifetimeLogFilename, "a")
+        except IOError as e:
+            print("Unable to open/create logfile \"{:s}\". {:s}".format(lifetimeLogFilename, str(e)))
+            return e.errno
+    return 0
+
+#
+# set new logging flags
+#   
+def applog_set_loggingFlags(newLoggingFlags):
+    global gLoggingFlags
+    gLoggingFlags = newLoggingFlags 
+
+#
+# shutdown this module
+#   
+def applog_shutdown():
+    try:
+        if gFileSessionLog:
+            gFileSessionLog.close()
+        if gFileLifetimeLog:
+            gFileSessionLog.close()
+    except IOError as e:
+        print("Unable to close logfile. {:s}".format(str(e)))
+
+ #
+ # Log message with specified level
+ #
+def applog(str, flags=APPLOGF_LEVEL_INFORMATIONAL):
+    if gLoggingFlags & (flags & APPLOGF_LEVEL_MASK):
+        if not (flags & APPLOGF_DONT_WRITE_TO_CONSOLE):
+            if flags & APPLOGF_LEVEL_ERROR:
+                print(str, file=sys.stderr)
+            else:
+                print(str)
+        # redirect output to log file(s)
+        timeStampStr = getDateTimeStr() + ": "
+        if gFileSessionLog:
+            print(timeStampStr + str, file=gFileSessionLog)
+        if gFileLifetimeLog:
+            print(timeStampStr + str, file=gFileLifetimeLog)
+
+
+ #
+ # Logging wrapper functions for each level
+ #
+def applog_i(s): 
+    applog(s, APPLOGF_LEVEL_INFORMATIONAL)
+def applog_v(s): 
+    applog(s, APPLOGF_LEVEL_VERBOSE)
+def applog_w(s): 
+    applog(s, APPLOGF_LEVEL_WARNING)
+def applog_e(s): 
+    applog(s, APPLOGF_LEVEL_ERROR)
+def applog_d(s):    
+    applog(s, APPLOGF_LEVEL_DEBUG)
+
+#
+# no-console equivalents
+#    
+def applog_i_nc(s): 
+    applog(s, APPLOGF_LEVEL_INFORMATIONAL | APPLOGF_DONT_WRITE_TO_CONSOLE)
+def applog_d_nc(s):    
+    applog(s, APPLOGF_LEVEL_DEBUG | APPLOGF_DONT_WRITE_TO_CONSOLE)
+
+
+#
+# Logging check-enabled functions, used to avoid
+# performance penalty of generating log message
+# if logging level is not enabled
+#
+def isDebugLog():
+    return (gLoggingFlags & APPLOGF_LEVEL_DEBUG)
+def isVerboseLog():
+    return (gLoggingFlags & APPLOGF_LEVEL_VERBOSE)
+