7 replies to this topic

[christhedon]

How would you improve this logging module?

Option Explicit
Public Enum LogLevel
  logDebug
  logInfo
  logwarn
  logError
  logFatal
  logNone
End Enum
Private mLogLevel As LogLevel
Const gLogToImmediate = False
Private mLogFullPath As String
Public Sub SetLogLevel(ByVal sLogLevel As String)
  Const sRoutineName As String = "SetLogLevel"
  Dim enumLogLevel As LogLevel
 
  On Error GoTo ErrHandler
 
  Select Case sLogLevel
   
    Case "logDebug"
    enumLogLevel = logDebug
    Case "logInfo"
    enumLogLevel = logInfo
    Case "logWarn"
    enumLogLevel = logwarn
    Case "logError"
    enumLogLevel = logError
    Case "logFatal"
    enumLogLevel = logFatal
    Case "logNone"
    enumLogLevel = logNone
    Case Else
    Err.Raise Errors.BadLogLevelChosen, sRoutineName, sLogLevel & " is not a valid log level"
  End Select
 
  mLogLevel = enumLogLevel
  Logger.Log "Log level set to " & sLogLevel & " i.e. " & mLogLevel, logInfo, True, True
Exit Sub
ErrHandler:
  ErrPersist.ReraiseError sRoutineName & " line:" & Erl & ", "
End Sub
Private Sub SetLogFullPath()
  mLogFullPath = GetLogDir() & GetTitle() & ".log"
End Sub
Public Function GetLogDir() As String
GetLogDir = Globals.GetTempDir()
End Function
Public Function GetLogFullPath() As String
  GetLogFullPath = GetLogDir() & GetTitle() & ".log"
End Function
Public Sub Log(ByVal logStr As String, ByVal loggingLevel As LogLevel, Optional ByVal displayOnStatusBar As Boolean = False, Optional ByVal displayInImmediate As Boolean = False)
'TODO:LOW update the error handling here. If logging fails it isn't critical for now.
Dim logStrWithTime As String
logStrWithTime = Now & "| " & logStr
On Error Resume Next
If loggingLevel >= mLogLevel Then
  'TODO:LOW Look into making this better
  If mLogFullPath = "" Then SetLogFullPath
  Open mLogFullPath For Append As 1
  Print #1, logStrWithTime
End If
If displayOnStatusBar Then
  Application.StatusBar = logStrWithTime
End If
If displayInImmediate And gLogToImmediate Then
  Debug.Print logStr
End If
On Error GoTo 0
End Sub
Public Sub CloseLogFile()
  On Error Resume Next
  Close 1
End Sub
Public Sub DeleteLargeLogFile(ByVal lAcceptableFileSzInBytes As Long)
On Error Resume Next
  Dim sFile As String
  sFile = GetLogFullPath()
  Debug.Print FileLen(sFile)
  If FileLen(sFile) > lAcceptableFileSzInBytes Then
    DeleteFile sFile
  End If
End Sub
Private Sub DeleteFile(sDeleteFile As String)
  On Error Resume Next
  If Len(Dir$(sDeleteFile)) > 0 Then
    SetAttr sDeleteFile, vbNormal
    Kill sDeleteFile
  End If
End Sub

[BlackRabbit]

I don't remember if in VBA you can set your enum as string, but if you could you wouldn't need the switch

 

and just in case, in the deletelargefile maybe you should check if the file isn't already open, because that will generate an error

[christhedon]

Thanks for responding. Unfortunately Enums can't have strings in VBA. I've got the on error resume next in the delete log file methods. If the file is locked I won't delete it. I kind of treated logging as something which if it fails its not critical. How would you change it?

[BlackRabbit]

Maybe you can make log files with the date, like: 2013-02-01.log and so on, and then every time you start you logs beyond a month.

[christhedon]

Thanks I might include the date as suggested. I'll update this post. Anyone feel free to update this post to make it better.

[christhedon]

Option Explicit
 
Public Enum LogLevel  logdebug  logInfo  
logwarn  logError  logFatal  logNoneEnd Enum
 
Private mLogLevel As LogLevelConst gLogToImmediate = FalsePrivate 
mLogFullPath As StringPrivate mFileNum As IntegerPublic Sub 
SetLogLevel(ByVal sLogLevel As String)
 
  Const sRoutineName As String = "SetLogLevel"  Dim 
enumLogLevel As LogLevel   On Error GoTo 
ErrHandler   Select Case 
sLogLevel       Case 
"logDebug"    enumLogLevel = logdebug    
Case "logInfo"    enumLogLevel = 
logInfo    Case "logWarn"    enumLogLevel 
= logwarn    Case "logError"    
enumLogLevel = logError    Case 
"logFatal"    enumLogLevel = logFatal    
Case "logNone"    enumLogLevel = 
logNone    Case Else    Err.Raise 
Errors.BadLogLevelChosen, sRoutineName, sLogLevel & " is not a valid log 
level"  End Select   mLogLevel = 
enumLogLevel  Logger.Log "Log level set to " & sLogLevel & " 
i.e. " & mLogLevel, logInfo, True, TrueExit Sub
 
ErrHandler:  ErrPersist.ReraiseError sRoutineName & " line:" 
& Erl & ", "
 
End Sub
 
Public Function GetLogLevel(ByVal eLogLevel As LogLevel) As 
String     Select Case 
eLogLevel       Case 
LogLevel.logdebug      GetLogLevel = 
"logDebug"    Case 
LogLevel.logInfo      GetLogLevel = 
"logInfo"    Case 
LogLevel.logwarn      GetLogLevel = 
"logWarn"    Case 
LogLevel.logError      GetLogLevel = 
"logError"    Case 
LogLevel.logFatal      GetLogLevel = 
"logFatal"    Case 
LogLevel.logNone      GetLogLevel = 
"logNone"  End Select End Function
 
Private Sub SetLogFullPath()  mLogFullPath = GetLogDir() & "\" 
& GetTitle() & ".log"End Sub
 
Public Function GetLogDir() As StringGetLogDir = Environ("TEMP")End 
Function
 
Public Function GetLogFullPath() As String  GetLogFullPath = 
GetLogDir() & "\" & GetTitle() & ".log"End Function
 
Public Sub Log(ByVal logStr As String, ByVal loggingLevel As LogLevel, 
Optional ByVal displayOnStatusBar As Boolean = False, Optional ByVal 
displayInImmediate As Boolean = False)
 
'TODO:LOW update the error handling here. If logging fails it isn't critical 
for now.Dim logStrWithTime As StringDim logStrWithLvlAndTime As 
String
 
On Error Resume Next
 
If loggingLevel >= mLogLevel Then  'TODO:LOW Look into making 
this better  
If mLogFullPath = "" Then SetLogFullPath  
logStrWithLvlAndTime = Now & "| " & GetLogLevel(loggingLevel) & " | 
" & logStr  mFileNum = FreeFile  Open mLogFullPath For 
Append As #mFileNum  Print #mFileNum, logStrWithLvlAndTime  
Close #mFileNum  DoEventsEnd If
 
If displayOnStatusBar Then  logStrWithTime = Now & "| " & 
logStr  Application.StatusBar = logStrWithTimeEnd If
 
If displayInImmediate And gLogToImmediate Then  Debug.Print 
logStrEnd If
 
On Error GoTo 0
 
End Sub
 
Public Sub CloseLogFile()  On Error Resume Next  Close 
#mFileNumEnd Sub
 
Public Sub DeleteLargeLogFile(ByVal lAcceptableFileSzInBytes As Long)On 
Error Resume Next  Dim sFile As String  sFile = 
GetLogFullPath()  Debug.Print FileLen(sFile)  If 
FileLen(sFile) > lAcceptableFileSzInBytes Then    
DeleteFile sFile  End IfEnd Sub
 
Private Sub DeleteFile(sDeleteFile As String)  On Error Resume 
Next  If Len(Dir$(sDeleteFile)) > 0 Then    
SetAttr sDeleteFile, vbNormal    Kill sDeleteFile  
End IfEnd Sub
 

I updated it so I can tail the log. Closes the file and uses free file num now and also I can see what level of log it is in the log so will be able to filter if need be. It seems better. Not sure if I need doevents or not.

Edited by christhedon, 06 March 2013 - 02:46 AM.

[BlackRabbit]

I think you got it! pin yourself a medal, you've done a good logger.

 

I wonder what will you be doing next

[Mitchell]

No, there is no option from within the application to enable logging. You are right, you have to use the Event Viewer.

Whenever there is a application crash, the error message would contain the log file for the same.

The reason why Outlook/Outlook express has a logging feature is because it will trace the path for email sent/recieved and find if the error lies in the application or other network devices.